TFS757-764HG
HiperTFS Family
www.powerint.com February 2011
Combined Two-Switch Forward and Flyback Power Supply Controllers
with Integrated High Voltage MOSFETs
™
HD
DC
Input
Main Output
Auxiliary/Standby
Output
RTN
G S
HiperTFS VDDH
L
FB
FB
EN
EN
BP
DSB
EN FB
Control,
Gate Drivers,
Level Shift
R
D
HS
PI-6200-102910
Two-Switch Forward
Transformer
Flyback
Transformer
Figure 1. Simplified Schematic of Two-Switch Forward and Flyback Converter.
Key Benefits
• Single chip solution for two-switch forward main and flyback
standby
• High integration allows smaller form factor and higher power
density designs
• Incorporates control, gate drivers, and three power
MOSFETS
• Level shift technology eliminates need for pulse transformer
• Protection features include: UV, OV, OTP, OCP, and SCP
• Transformer reset control
• Prevents transformer saturation under all conditions
• Allows >50% duty cycle operation
• Reduces primary side RMS currents and conduction losses
• Standby supply provides built-in overload power compensation
• Up to 434 W total output power in a highly compact package
• Up to 550 W peak
• High efficiency solution easily enables design to meet
stringent efficiency specifications
• >90% efficiency at full load
• No-load regulation and low losses at light-load
• Simple clip mounting to heat sink without need for insulation pad
• Halogen free and RoHS compliant
Applications
• PC
• Printer
• LCD TV
• Video game consoles
• High-power adapters
• Industrial and appliance high-power adapters
Output Power Table
Product
Two-Switched Forward
380 V
Flyback
100 V - 400 V
Continuous
(25 °C)
Continuous
(50 °C)
Peak
(50 °C) 50 °C
TFS757HG 193 W 163 W 228 W 20 W
TFS758HG 236 W 200 W 278 W 20 W
TFS759HG 280 W 235 W 309 W 20 W
TFS760HG 305 W 258 W 358 W 20 W
TFS761HG 326 W 276 W 383 W 20 W
TFS762HG 360 W 304 W 407 W 20 W
TFS763HG 388 W 327 W 455 W 20 W
TFS764HG 414 W 344 W 530 W 20 W
Table 1. Output Power Table (See Notes on page 13).
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Section List
Description .................................................................................................................................................................. 3
Product Highlights ...................................................................................................................................................... 3
Pin Functional Description ......................................................................................................................................... 5
Pin Configuration ...................................................................................................................................................... 5
Functional Block Diagram .....................................................................................................................................6-7
Functional Description ............................................................................................................................................... 8
Output Power Table ............................................................................................................................................... 13
Design, Assembly, and Layout Considerations .................................................................................................... 14
Application Example ................................................................................................................................................. 20
Absolute Maximum Ratings ..................................................................................................................................... 23
Parameter Table ..................................................................................................................................................... 23
Typical Performance Characteristics .................................................................................................................29-33
Package Details ........................................................................................................................................................ 34
Part Ordering Information......................................................................................................................................... 35
Part Marking Information ......................................................................................................................................... 35
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TFS757-764HG
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Description
The HiperTFS device family members incorporate both a
high-power two-switch-forward converter and a mid-power
flyback (standby) converter into a single, low-profile eSIP™
power package. The single chip solution provides the controllers
for the two-switch-forward and flyback converters, high- and
low-side drivers, all three of the high-voltage power MOSFETs,
and eliminates the converter’s need for costly external pulse
transformers. The device is ideal for high power applications
that require both a main power converter (two-switch forward)
up to 414 W, and standby converter (flyback) up to 20 W.
HiperTFS includes Power Integrations’ standard set of comprehen-
sive protection features, such as integrated soft-start, fault and
over-load protection, and hysteretic thermal shutdown.
HiperTFS utilizes advanced power packaging technology that
simplifies the complexity of two-switch forward layout, mounting
and thermal management, while providing very high power
capabilities in a single compact package. The devices operate
over a wide input voltage range, and can be used following a
power-factor correction stage such as HiperPFS.
Two-switch-forward power converters are often selected for
applications demanding cost-effective efficiency, fast transient
response, and accurate tolerance to line voltage fluctuation. The
two-switch-forward controller incorporated into HiperTFS
devices improves on the classic topology by allowing operation
considerably above 60% duty cycle. This improvement reduces
RMS currents conduction losses, minimizes the size and cost of
the bulk capacitor, and minimizes output diode voltage ratings.
The advanced design also includes transformer flux reset
control (saturation protection) and charge-recovery switching of
the high-side MOSFET, which reduces switching losses. This
combination of innovations yields an extremely efficient power
supply with smaller MOSFETs, fewer passives and discrete
components, and a lower-cost transformer.
HiperTFS’s flyback standby controller and MOSFET solution is
based on the highly popular TinySwitch™ technology used in
billions of power converter ICs due to its simplicity of operation,
light load efficiency, and rugged, reliable, performance. This
flyback converter can provide up to 20 W of output power and
the built in overload power compensation reduces component
design margin.
Product Highlights
Protected Two-Switch Forward and
Flyback Combination Solution
• Incorporates three high-voltage power MOSFETs, main and
standby controllers, and gate drivers
• Level shift technology eliminates need for pulse transformer
• Programmable line undervoltage (UV) detection prevents
turn-off glitches
• Programmable line overvoltage (OV) detection; latching and
non-latching
• Accurate hysteretic thermal shutdown (OTP)
• Accurate selectable current limit (main and standby)
• Output over-current protection (OCP)
• Fully integrated soft-start for minimum start-up stress
• Simple fast AC reset
• Reduced EMI
• Synchronized 66 kHz forward and 132 kHz flyback
converters
• Frequency jitter
• Eliminates up to 30 discrete components for higher reliability
and lower cost
Asymmetrical Two-Switch Forward Reduces Losses
• Allows >50% duty cycle operation
• Reduces primary side RMS currents and conduction losses
• Minimizes the size and cost of the bulk capacitor
• Allows reduced capacitance or longer hold-up time
• Allows lower voltage output diodes
• Transformer reset control
• Prevents transformer saturation under all conditions
• Extends duty cycle to satisfy AC cycle drop out ride through
• Duty cycle soft-start with 115% current limit boost
• Satisfies 2 ms ~ 20 ms start-up with large capacitance at
output
• Output short circuit protection (SCP) with auto-restart
• Remote ON/OFF function
• Voltage mode controller with current limit
20 W Flyback with Selectable Power Limit
• TinySwitch-III based converter
• Selectable power limit (10 W, 12.5 W, 15 W, or 20 W)
• Built-in overload power compensation
• Flat overload power vs. input voltage
• Reduces component stress during overload conditions
• Reduces required design margin for transformer and output
diode
• Output overvoltage (OV) protection with fast AC reset
• Latching, non-latching, or auto-restart
• Auto-restart
Advanced Package for High Power Applications
• 434 W output power capability in a highly compact package
• Up to 550 W peak
• Simple clip mounting to heat sink
• Can be directly connected to heat sink without insulation pad
• Provides thermal impedance equivalent to a TO-220
• Heat slug connected to ground potential for low EMI
• Staggered pin arrangement for simple routing of board traces
and high-voltage creepage requirements
• Single power package for two power converters reduces
assembly costs layout size
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TFS757-764HG
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Table 2. Summary of Differences Between HiperTFS and Other Typical High Power Supplies.
Function
Typical Two-Switch
Forward HiperTFS Advantages of HiperTFS
Nominal Duty Cycle 33% 45% Wider duty cycle reduces RMS switch currents by 17%.
Reduces RDS(ON) losses by 31%
Maximum Duty Cycle <50% 63%
Switch Current (RMS) 100% 83%
Output Catch Diode VO + VD/DMAX VO + VD/DMAX Lower losses. Wider DMAX lowers catch diode rating by
(1-(50%/63%)) = 21% reduction in catch diode voltage
rating
Clamp Voltage Reset diodes from zero
to VIN
Reset from zero to
(VIN + 130)
With fast/slow diode combination, allows charge
recovery to limit high-side COSS loss
Thermal Shutdown --- 118 °C Shutdown /
55 °C hysteresis
HiperTFS provides integrated OTP device protection
Current Sense Resistor 0.5 V drop (0.33 W at
300 W)
Sense resistor not
required
Improved efficiency. MOSFET RDS(ON) sense eliminated
need for sense resistor
High-Side Drive Requires gate-drive
transformer (high cost)
Built in high-side drive Lower cost; component elimination. Removes
high-cost gate-drive transformer (EE10 or toroid)
Component Count Higher Lower Saves up to 50 components, depending on specification.
TinySwitch Overload Power
Compensation vs. Input Voltage
--- Built-in compensation Safer design; easier to design power supply. Flattens
overload output power over line voltages
Package Creepage TO-220 = 1.17 mm eSIP16/12 = 2.3 mm/
3.3 mm
HiperTFS meets functional safety spacing at package
pins
Package Assembly 2 × TO-220 package, 2
× SIL (insulation)
1 Package No SIL (insulation) pad required
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Pin Functional Description
MAIN DRAIN (D) Pin
Drain of the low-side MOSFET transistor forward converter.
STANDBY DRAIN (DSB) Pin
Drain of the MOSFET of standby power supply.
GROUND (G) Pin
This pin gives a signal current path to the substrate of the
low-side controller. This pin is provided to allow a separate
Kelvin connection to the substrate of the low-side controller to
eliminate inductive voltages that might be developed by high
switching currents in the SOURCE pin. The GROUND pin is
not intended to carrier high currents, instead it is intended as a
voltage-reference connection only.
SOURCE (S) Pin
SOURCE pin that is common to both the standby and main
supplies.
RESET (R) Pin
This pin provides information to limit the maximum duty cycle as a
function of the current fed into the RESET pin during the off-time
of the main converter MOSFET. This pin can also be pulled up to
bypass to signal remote ON/OFF of the main converter only.
ENABLE (EN) Pin
This is the ENABLE pin for the standby controller. Prior to the
start-up a resistor connected from ENABLE to BYPASS, can be
detected to select one of several internal current limits.
LINE-SENSE (L) Pin
This pin provides input bulk voltage line-sense function. This
information is used by the undervoltage and overvoltage
detection circuits for both main and standby. The pin can also
be pulled up to BYPASS or be pulled down to SOURCE to
implement a remote ON/OFF of both standby and main
supplies simultaneously. The LINE-SENSE pin works in
conjunction with the RESET pin to implement a duty-cycle limit
function. Also the LINE-SENSE pin compensates the value of
standby current limit so as to flatten the output overload
response as a function of input voltage.
FEEDBACK (FB) Pin
This pin provides feedback for the main two transistor forward
converter. An increase in current sink from FEEDBACK pin to
ground, will lead to a reduction in operating duty cycle. This pin
also selects the main device current limit at start-up (in a similar
manner to ENABLE pin).
BYPASS (BP) Pin
This is the decoupled operating voltage pin for the low-side
controller. At start-up the bypass capacitor is charged from an
internal device current source. During normal operation the
capacitor voltage is maintained by drawing current from the
low-side bias winding on the standby power supply. This pin is
also used to implement remote ON/OFF for the main controller.
This is done by driving extra current into the BYPASS pin when
we want to turn-on the Main controller. The BYPASS pin also
implements a latch-off function to disable standby and main
when the BP pin current exceeds latching threshold. Latch is
reset when LINE-SENSE pin falls below UV (off) standby
threshold.
HIGH-SIDE OPERATING VOLTAGE (VDDH) Pin
This is the high-side bias (VDD) of approximately 11.5 V. This
voltage is maintained with current from a high-side bias winding
on the main transformer and/or from a bootstrap diode from the
low-side standby bias supply.
HIGH-SIDE SOURCE (HS) Pin
SOURCE pin of the high-side MOSFET.
HIGH-SIDE DRAIN (HD) Pin
DRAIN pin of the high-side MOSFET. This MOSFET is floating
with respect to low-side source and ground.
Figure 2. Pin Configuration.
PI-5290-110510
16
D
DSB
G
S
R
EN
HD
HD
HS
S
S
L
FB
HS
HD
VDDH
BP
141310 1191 3 5 6 7 8
H Package (eSIP-16/12)
Exposed Pad
(Backside) Internally
Connected to SOURCE
Pin (see eSIP-16B
Package Drawing)
Exposed Metal
(On Edge)
Internally
Connected
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TFS757-764HG
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PI-5263-021511
PWM
COMPARATOR
PWM
INPUT THERMAL SD
CONTROLLED
TURN-ON
GATE DRIVER
CURRENT LIMIT
COMPARATOR
SOURCE (S)
S
R
Q
-
+
BYPASS (BP)
LINE-SENSE (L)
RESET (R)
FEEDBACK (FB)
and MAIN CURRENT
LIMIT SELECT
STOP
HSD1 HSD2
FAULT PRESENT
LV SAW
D2MAX CLK2
MAIN REMOTE-ON
+
-
LEADING
EDGE
BLANKING
R
L
DUTY
CYCLE
LIMIT
DMAX
GATE
CLK
ON
DRAIN (D)
VBG
LINE
SENSE
LV
POWER ON
ILIMIT
SELECT
VILIMIT
DSS
SOFT-START
PWM INPUT
REMOTE
OFF
REMOTE OFF
GATE
HS
3 V+VT
Figure 3. Functional Block Diagram for Two-Switch Forward Converter.
HIGH-SIDE
OPERATING VOLTAGE (VDDH)
HSD1
HSD2
12 V 11.1 V
9.9 V
HIGH-SIDE
DRAIN (HD)
HIGH-SIDE
SOURCE (HS)
VDDH
UNDERVOLTAGE
PI-5516-060410
+
S
R
Q
DISCRIMINATOR
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TFS757-764HG
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Figure 4. Functional Block Diagram for Flyback/Standby Converter.
PI-5264-020510
CLOCK
CLK2
5.7 V
4.7 V
SOURCE (S)
S
R
Q
DCMAX
D2MAX
SAW
BYPASS (BP)
+
-
VILIMIT
FAULT
PRESENT
CURRENT LIMIT
COMPARATOR
ENABLE
LEADING
EDGE
BLANKING
THERMAL
SHUTDOWN
+
-
STANDBY DRAIN (DSB)
BYPASS PIN
UNDER-VOLTAGE
LV (LINE VOLTAGE)
SAW D2MAX
CLK2 FAULT
PRESENT
OSCILLATOR
THERMAL SD
1.0 V + VT
ENABLE (EN)
and STANDBY
CURREN LIMIT
SELECT
Q
115 µA
RESET
AUTO-
RESTART
COUNTER
JITTER
1.0 V
6.0 V
ENABLE PULL
UP RESISTOR
SELECT AND
CURRENT
LIMIT STATE
MACHINE
MAIN
REMOTE
ON/
OVP
LATCH OFF
VIN
ILIMIT
ADJUST
MAIN
REMOTE
ON
REGULATOR
5.7 V
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Functional Description
The HiperTFS contains two switch-mode power supply
controllers and associated low-side MOSFET’s along with
high-side driver and high-side MOSFET.
• The HiperTFS two-switch forward includes a controller along
with low-side power MOSFET, high-side power MOSFET and
high-side driver. This device operates in voltage mode (linear
duty-cycle control) at fixed frequency (exactly half the operat-
ing frequency of the standby controller). The control converts
a current input (FEEDBACK pin), to a duty-cycle at the open
drain MOSFET MAIN DRAIN pin decreasing duty-cycle with
increasing sourced current from the FEEDBACK pin.
• The HiperTFS flyback includes a controller and power MOSFET
which is based on TinySwitch-III. This device operates in
multi-level ON/OFF current limit control mode. The open drain
MOSFET (STANDBY DRAIN pin) is turned on when the sourced
current from the ENABLE pin is below the threshold and
switching is disabled when the ENABLE pin current is above
the threshold.
In addition to the basic features, such as the high-voltage
start-up, the cycle-by-cycle current limiting, loop compensation
circuitry, auto-restart and thermal shutdown, the HiperTFS main
controller incorporates many additional functions that reduce
system cost, increase power supply performance and design
flexibility.
Main Converter General Introduction
The Main converter for the HiperTFS, is a two-switch forward
converter (although the HiperTFS could be used with other
two-switch topologies). This topology involves a low-side and
high-side power MOSFET, both of which are switched at the
same time. In the case of the HiperTFS, the low-side MOSFET
is a 725 V MOSFET (with the substrate connected to the
SOURCE pin). The high-side MOSFET is a 530 V MOSFET
(with the substrate connected to the HIGH-SIDE DRAIN (HD)
pin). As such the substrate of both low-side and high-side
MOSFET’s are tied to quiet circuit nodes (0 V and VIN
respectively), meaning that both MOSFETs have electrically
quiet substrates – good for EMI.
The low-side MOSFET has a very low COSS capacitance and
thus can be hard-switched without performance penalty. Due
to the external clamp configuration it is possible to substantially
soft-switch the high-side MOSFET at high-loads (thus
eliminating a large proportion of high-side capacitive switching
loss) and improving efficiency. The higher breakdown voltage
on the low-side MOSFET allows the transformer reset voltage to
exceed the input voltage, and thus allow operation at duty
cycles greater than 50%. Higher duty cycle operation leads to
lower RMS switch currents and also lower output diode
voltage-rating, both of which contribute to improved efficiency.
The HiperTFS also contains a high-side driver to control the
high-side MOSFET. This internal high-side driver eliminates the
need for a gate-driver transformer, an expensive component
that is required for many other two-switch forward circuits.
Main Start-Up Operation
Once the flyback (standby) converter is up and running, the
main converter can be enabled by two functions. The first
condition is that the BYPASS pin remote-on current must
exceed the remote-on threshold (IBP(ON)), provided by an external
remote ON/OFF circuit. This current threshold has a hysteresis
to prevent noise interference. Once the BYPASS remote-on
has been achieved, the HiperTFS also requires that the LINE-
SENSE pin current exceeds the UV Main-on (IL(MA-UVON)), which
corresponds to approximately 315 VDC input voltage when
using a 4 MW LINE-SENSE pin resistor. Once this LINE-SENSE
pin threshold has been achieved the HiperTFS will enter a 12 ms
pre-charge period (tD(CH)) to allow the PFC-boost stage to reach
regulation before the main applies a load to the bulk-capacitor.
Also during this pre-charge period the high-side driver is
charged via the boot-strap diode from the low-side auxiliary
voltage, and is charged when the main low-side MOSFET turns
Figure 5. Switching Frequency Jitter (Idealized VDRAIN Waveforms).
PI-4530-041107
fOSC -
4 ms
Time
Switching
Frequency
VDRAIN
fOSC +
Figure 6. Supply Start-Up Sequence by Remote ON.
VIN
Standby
Output
Main
Output
12 ms
385 V
Main
Primary
Current
Remote ON
12 ms 32 ms
t
t
t
t
t
PI-5619a-102710
100% ILIM
115% I
LIM
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on, while the main high-side MOSFET is held off. By the end of
the pre-charge period, the PFC-boost voltage should be at or
above the nominal boost voltage. The HiperTFS begins
switching, going through the soft-start period (tSS). During the
soft-start period the maximum duty cycle starts at 30% and is
ramped during a 12 ms period to the maximum. The ramped
duty cycle controls the rise slew rate of the output during
start-up, allowing well controlled start-up and also facilitates a
smooth transition when the control loop takes over regulation
towards the end of soft-start. Also during a 32 ms period
(starting at the beginning of soft-start), the main current limit is
boosted to 115% of the nominal selected Main current. This
allows the main to start-up within the required period for the
application (typically < 20 ms for PC main applications), when
there is a substantial capacitive load on the output. After the
soft-start period, the current limit returns to 100% of the
nominal selected current limit.
Main Converter Control FEEDBACK (FB) Pin Operation
The FEEDBACK pin is the input for control loop feedback from
the main control loop. During normal operation the FEEDBACK
pin is used to provide duty cycle control for the main converter.
The system output voltage is detected and converted into a
feedback current. The main converter duty cycle will reduce as
more current is sourced from the FEEDBACK pin, reaching zero
duty cycle at approximately 2.1 mA. The nominal voltage of the
FEEDBACK pin is maintained at approximately 3.5 V. An
internal pole on the FEEDBACK pin is set to approximately
12 kHz, in order to facilitate optimal control loop response.
The maximum duty cycle of the main converter is defined by the
LINE-SENSE pin and RESET pin behavior and is a dynamically
calculated value according to cycle-by-cycle conditions on the
LINE-SENSE pin and RESET pin.
Main High-Side Driver
The high-side driver is a device that is electrically floating at the
potential of the HIGH-SIDE MOSFET SOURCE (HS) pin. This
device provides gate-drive for the high-side Main MOSFET. The
low-side main and high-side main MOSFET’s switch simul-
taneously. The high-side driver has a HIGH-SIDE OPERATING
VOLTAGE supply pin. External circuitry provides a current
source into this HIGH-SIDE OPERATING VOLTAGE pin. The
high-side operating voltage has an internal 12 V shunt-regulator.
The device consumes approximately 2 mA when driving the
high-side MOSFET.
The HIGH-SIDE OPERATING VOLTAGE pin has an undervoltage
lock-out threshold, to prevent gate-drive when the supply voltage
drops below a safe threshold. At power-up the high-side driver
remains in the off-state, until the HIGH-SIDE OPERATING
VOLTAGE pin is charged above 10.5 V, at which point the
high-side driver becomes active. The high-side driver is initially
charged via a boot-strap diode connected via a diode to the
HIGH-SIDE OPERATING VOLTAGE pin from the low-side
standby auxiliary supply (approximately 12 V). During start-up
the high-side MOSFET remains off, but the low-side MOSFET is
turned on for a period of 14 ms to allow pre-charge of the
high-side operating voltage to 12 V. After this period, the high-
side operating voltage is supplied by a forward-winding coupled
to the main transformer. This floating winding provides energy
every time the main converter switches one cycle. The
operating power for high-side operating voltage can also be
provided from a floating winding on the standby supply.
However this would continue delivering power even when the
main converter is in remote-off, and thus is considered
undesirable from a standby light-load efficiency point of view.
Once the high-side driver is operating it receives level-shifted
drive commands from the low-side device. These drive
commands cause both turn-on and turn-off drive of the
high-side main MOSFET simultaneously with that of the
low-side main MOSFET.
The high-side driver also contains a thermal shutdown on-chip,
but this is set to a temperature above the thermal shutdown
temperature of the low-side device. Thus the low-side will
always shutdown first.
Main Converter Maximum Duty Cycle
The LINE-SENSE pin resistor converts the input voltage into an
LINE-SENSE pin current signal. The RESET pin resistor
converts the reset voltage into an RESET pin current signal.
The LINE-SENSE pin and RESET pin currents allow the
HiperTFS to determine a maximum duty cycle envelope on a
cycle-by-cycle basis. This feature ensures sufficient time for
transformer reset on a cycle-by-cycle basis and also protects
against single-cycle transformer saturation and at high-input
voltage by limiting the maximum duty cycle to prevent the
transformer from reaching an unsafe flux density during the
on-time period. Both of these features allow the optimal
performance to be obtained from the main transformer. The
duty cycle limit is trimmed during production.
The LINE-SENSE pin and RESET pin are sampled just before
the turn-on of the next main cycle. This is done to sample at a
point when there is minimal noise in the system. Due to the low
current signal input to the LINE-SENSE pin and RESET pin,
care should be taken to prevent noise injection on these pins
(see Applications section layout guidelines for details).
Main On-Chip Current Limit with External Selection
During start-up, the FEEDBACK pin and ENABLE pin are both
used to select internal current limits for the main and standby
converters respectively. The detection period occurs at the
initial start-up of the device, and before the main or standby
MOSFETs start switching. This is done to minimize noise
interference.
Figure 7. PWM Duty Cycle vs. Control Current.
63%
78%
0%
1 mA 2.1 mA
Duty (D)
FEEDBACK Pin
Current IFB
IL = 60 µA
IR = 170 µA
Typical IL and IR
currents at VMIN
Limited by L & R
pin duty limit
PI-5885-082610
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A resistor RFB is connected from the BYPASS pin to the
FEEDBACK pin. This resistor feeds current into the FEEDBACK
pin (who’s voltage is clamped to approximately 1 V during this
detection period). The current into the FEEDBACK pin is
determined by the value of the resistor, and thus the input
current (and indirectly the resistor value), select an internal
current limit according to the following table.
Main Line Undervoltage Detection (UV)
The LINE-SENSE pin resistor is connected to VIN and generates
a current signal proportional to VIN. The LINE-SENSE pin voltage
is held by the device at 2.35 V. The LINE-SENSE pin current
signal is used to trigger under/overvoltage thresholds for both the
standby and main converters. Assuming a LINE-SENSE pin
resistor of 4 MW, the standby will begin operating when the
LINE-SENSE pin current exceeds the (IL(SB-UVON)) threshold,
nominally approximately 100 V. However the main is still held in
the off-state, until the LINE-SENSE pin current exceeds the
(IL(MA-UVON)) threshold, nominally 315 V for 4 MW. There is
hysteresis for both main and standby undervoltage-off
thresholds, to allow sufficient margin to avoid accidental
triggering, and to provide sufficient margin to meet hold-up time
requirements. Bear in mind that the main converter may start to
loose regulation before it finally shuts down. This is because
the dynamic duty cycle limit may clamp the duty cycle below
that required for regulation at lower input voltages. Once the
input voltage falls below the 215 V (IL(MA_UVOFF)) threshold, the
main will shutdown but standby will continue to operate. The
standby will turn off when the input voltage drops below
approximately 40 V (IL(SB-UVON)).
Figure 9. Current Limit Selection.
Table 3. FEEDBACK Pin Main Current Limit Selection.
IFB
(Threshold) ILIMIT
REN(SELECT)
(1%)
0.0-5.1 mA L1 60% mA Open kW
5.1-11.9 mA L2 80% mA 511.0 kW
11.9-23.8 mA L3 100% mA 232.0 kW
UV(ON)STANDBY, I(L) = 25 µA
4.7 V
1 V
5.7 V
I(L)
V(BP)
V(FB)
V(EN)
TSELECT - current limit selection occurs here during
device start-up and before power supply switching
2.7 V
2.2 V
6.0 V after
standby
acheives
regulation
PI-5975-102610
Figure 8. Duty Cycle Limit vs. Ratio of R Pin Current Over L Pin Current.
0.5 1.0 1.5 2.0 3.02.5
IR/IL
Duty Cycle Limit
0.7
0.6
0.5
0.4
PI-5977-061010
IL = 60 µA
IL = 90 µA
IL = 100 µA
IL = 115 µA
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www.powerint.com
Main Reset Overvoltage Detection
There is also an overvoltage threshold for the RESET pin. When
triggered, the RESET overvoltage will shutdown only the Main,
leaving the Standby in operation.
Standby Power General Introduction
The standby is a wide range power supply, typically a flyback
converter, operating over a wide input range (85-265 VAC) and
delivering up to 20 W continuous output power. The standby
power supply provides two functions in most high-power
applications. It provides a direct secondary output but also
provide bias power to other primary-side devices (in particular
typically a PFC boost converter).
The HiperTFS standby retains most features of the TinySwitch-III,
such as auto-restart, thermal shutdown, multi-level current limit
ON/OFF control, etc. The HiperTFS standby controller has a
few differences versus TinySwitch-III:
1. There are 4 current limits that are selected via the ENABLE
pin (rather than by using different BYPASS pin capacitors as
in TinySwitch-III). There are 4 user selectable current limits
500, 550, 650, 750 mA design for secondary standby
output power of 10, 12.5, 15 and 20 W.
2. Secondary OVP latching shutdown. This is triggered via a
current in excess of the BYPASS pin latching shutdown
threshold (IBP(SD) = 15 mA).
3. Dedicated LINE-SENSE pin for line-voltage detection providing
absolute UV and OV ON/OFF thresholds (unlike TinySwitch-III
which detects input voltage only during restart).
4. Current limit is compensated as a function of input voltage
to maintain a flat overload characteristic versus input voltage.
In a high-power system, the standby power supply is the first
power supply to begin operating. The main converter cannot
begin working until the standby is in operation. Likewise the
main converter will shutdown at a higher-voltage than the standby
and thus the standby is always the last power supply to
shutdown.
Standby On-Chip Current Limit with External Selection
During start-up, the FEEDBACK pin and ENABLE pin are both
used to select internal current limits for the Main and Standby
converters respectively. The detection period occurs at the
initial start-up of the device (just after BYPASS pin voltage of
4.7 V is achieved), and before the main or standby MOSFETs
start switching. This is done to minimize noise interference.
The ENABLE pin works in a similar way to the FEEDBACK pin
selection. The only difference being that the ENABLE pin is not
clamped to 1 V during selection, instead remaining at 2.35 V
during the detection period. Thus the selection resistor values
Figure 10. Main and Standby Start-Up.
I EN
(Threshold) ILIMIT
R EN (Select)
(1%)
0.0-8.5 mA L1 500 mA Open kW
8.5-17.7 mA L2 650 mA 280.0 kW
17.7-33.0 mA L3 750 mA 137.0 KW
33.0-66.0 mA L4 550 mA 63.4 kW
Table 4. ENABLE Pin Standby Current Limit Selection.
VIN
Supply Start-Up Sequence
Standby
Output
Main
Output
VBP
12 ms
385 V
315 V
100 V
30 V
2-20 ms
6.0 V
4.7 V
5.7 V
PI-5611a-062710
Figure 11. L and R Pin Duty Limit Mode.
VIN
Standby
Output
Main
Output
385 V
300 V
240 V
40 V
PI-5612a-060910
tHOLDUP
≥ 20 ms Typically turned off by
secondary supervisor
circuit, once regulation
below limit
t1t2t3t4
RLRR
To VIN To Clamp
Reset Circuit
R
HiperTFS
L
Rev. C 02/11
12
TFS757-764HG
www.powerint.com
are slightly different for the ENABLE pin versus the FEEDBACK
pin. The ENABLE pin internal current selection is chosen
according to the above table.
The current limit selection for both FEEDBACK pin and ENABLE
pin takes place when the BYPASS pin first reaches 4.7 V. Once
the short detection period is complete, the BYPASS pin is
ramped on up to 5.7 V, and the FEEDBACK pin is allowed to
float to it’s nominal voltage of 3.5 V.
Standby Line Compensated Current Limit
to Flatten Output Overload
For many power supplies, the power output capability of the
power supply increases dramatically as the input voltage
increases. This means that most power supplies are able to
deliver much more power (up to 30-40% more power), into a
fault overload when operating at higher input voltage (versus
operating at lower input voltage). This can cause a problem
since many specifications require that the output overload
power capability of the device is more tightly managed.
In the case of the HiperTFS, the standby current limit is adjusted
as a function of line (input voltage), in such a ways as to always
provide substantially the same maximum overload power
capability. The input voltage is detected via the LINE-SENSE
pin current and the internal standby current limit of the device is
adjusted accordingly on a cycle-by-cycle basis. This means that
the HiperTFS standby will only deliver approximately 5% more
overload power at high-line as it did at low-line. This feature
provides a much safer design.
Standby Line Undervoltage Detection (UV)
The LINE-SENSE pin resistor is connected to VIN and generates
a current signal proportional to VIN. The LINE-SENSE pin
voltage is held by the device at 2.35 V. The LINE-SENSE pin
current signal is used to trigger under/overvoltage thresholds for
both the standby and main converters. Assuming a LINE-SENSE
pin resistor of 4 MW, the standby will begin operating at
approximately 100 V (as defined by IL(SB_UVON)). The standby will
shutdown if regulation is lost when input voltage is below 100 V.
However the standby will be forced to shutdown if this input
voltage drops below approximately 40 V (as defined by IL(SB-UVOFF)).
Main and Standby Oscillator and Switching Frequency
The standby converter operates at a frequency of 132 kHz. The
main converter operates at exactly half that frequency at 66 kHz.
The two converters both include a common frequency jitter
profile that varies the switching frequency ±4 kHz for the main
(twice the jitter frequency range ±8 kHz for the standby), during
a 4 ms jitter period. The frequency jitter helps reduce quasi-
peak and average EMI emissions.
It should be noted that the HiperTFS has a collision avoidance
scheme in which the main converter is the master and the
standby is the slave, which avoids the main and standby switching
at exactly simultaneous moments. The most common
condition would be close to 50% duty cycle, if the main (master)
is about to switch (turn-off), then the standby (slave), waits for
short instant (200 ns) before starting it’s next cycle. The
standby is used as the slave, since the ON/OFF control of the
HiperTFS standby is less easily disrupted by sudden delays in
switching, versus the linear control loop of the main converter.
Standby and Main Thermal Shutdown
The HiperTFS provides a thermal shutdown function, (OTP) that
protects the HiperTFS. This hysteretic thermal shutdown allows
the device to automatically recover from any thermal fault event.
The thermal shutdown is triggered at a die-temperature of
approximately 118 °C and has a high hysteresis to ensure the
average device temperature is within safe levels. In a well
designed system the HiperTFS thermal shutdown is not
triggered during any normal operation and is only present as a
safety feature to protect against abnormal or fault conditions.
BYPASS (BP) Pin Operation
The BYPASS (BP) pin is the supply pin for the entire HiperTFS
device. The BYPASS pin is internally connected to a high-voltage
current source via the STANDBY DRAIN power MOSFET. This
high-voltage source will charge the BYPASS pin to 4.7 V during
initial power up. Once the BYPASS pin reaches 4.7 V, the
BYPASS pin will check the main and standby current limit
selection (FEEDBACK pin and ENABLE pin resistors respectively).
This selection takes a very short period, thereafter the BYPASS
pin continues being charged until it reaches 5.7 V, at which
point the standby power supply is ready to begin operation.
Like the TinySwitch-III the high-voltage current source will
continue to charge the BYPASS pin if it droops below 5.7 V.
However in most typical applications, a resistor (typically 7.5 kW)
is connected from primary bias (12 V) to the BYPASS pin. This
resistor provides the operating current to the BYPASS pin,
preventing the need to draw power from the high-voltage
current source. Like the TinySwitch-III, the BYPASS pin contains
a shunt regulator, which will be enabled if the BYPASS pin
voltage is externally driven above 5.7 V. The BYPASS pin shunt
current is used for two functions:
1. First, for a 4 mA threshold (IBP(ON)) for main remote-on. When
the BYPASS pin current exceeds this threshold, the main is
enabled.
Figure 12. Shows Output Overload Power for Both Compensated and
Uncompensated Standby Current Limits.
50 100 150 200 250 300 400 450350
VIN DC (V)
Output Overload Power (%)
150
140
130
120
100
110
90
80
PI-5884-052510
Not Compensated
Compensated
Rev. C 02/11
13
TFS757-764HG
www.powerint.com
Output Power Table
Product2
Two-Switched Forward
380 V
Flyback
100 V - 400 V
Continuous1
(25 °C)
Continuous1
(50 °C)
Peak
(50 °C) 50 °C
TFS757HG 193 W 163 W 228 W 20 W
TFS758HG 236 W 200 W 278 W 20 W
TFS759HG 280 W 235 W 309 W 20 W
TFS760HG 305 W 258 W 358 W 20 W
TFS761HG 326 W 276 W 383 W 20 W
TFS762HG 360 W 304 W 407 W 20 W
TFS763HG 388 W 327 W 455 W 20 W
TFS764HG 414 W 344 W 530 W 20 W
Table 5. Output Power Table.
Notes:
1. Maximum practical continuous power in an open frame design with adequate
heat sinking (assuming heat sink θC-A of <4 °C/W), measured at specified
ambient temperature (see Key Applications Considerations for more information).
2. Package: eSIP16/12. (Note: Direct attach to heat sink, does not require
insulation SIL pad)
2. Second a 15 mA threshold (IBP(SD))for standby secondary OVP
latch-off. When the BYPASS pin current exceeds this
threshold, the standby and main converters are latched-off.
This latch can be reset by pulling the LINE-SENSE pin below
the line undervoltage threshold (IL(SB-UVOFF)), or by discharging
the BYPASS pin below 4.7 V.
Note: unlike the TinySwitch-III the HiperTFS BYPASS pin capacitor
does not provide any programming capability. Instead the
recommended BYPASS pin capacitor should always be a 1 mF
(ceramic) capacitor.
Main and Standby Line Overvoltage Detection (OV)
The overvoltage threshold is included in the device, and can be
used to disable the device during overvoltage (with the use of
an additional external signal Zener). The overvoltage threshold
is set sufficiently high to prevent accidental triggering during
boost PFC overshoot conditions. When the overvoltage
condition is triggered, it will simultaneously shutdown both the
Main and Standby. The overvoltage feature is intended for use
with external components (circuitry), to program the overvoltage
threshold independently of the undervoltage thresholds (see the
Applications section for details).
High-Power eSIP Package
The HiperTFS package is designed to minimize the physical size
of the device, while maintaining a low thermal impedance and
sufficient electrical spacing for the pins. The package has 12
functional pins with 4 pins removed for increased pin-to-pin
spacing between high-voltage pins. The low-side two-switch
forward and flyback MOSFETs have a thermal impedance of
less than 1 °C/W to the exposed pad on the back of the
package. Since this pad is referenced to the SOURCE pin
(Source), it is at electrical ground potential and thus can be
connected to the heat sink without need for electrical insulation.
The high-side MOSFET is over-molded to achieve electrical
isolation and thus also allows direct connection to the heat sink.
Rev. C 02/11
14
TFS757-764HG
www.powerint.com
Design, Assemble and Layout Considerations
Power Table
The data sheet power table (Table 1, page 1) represents the
maximum advised continuous power based on the following
conditions;
1. Typical multi-output PC main with the following outputs +12 V,
+5 V, +3.3 V, -12 V, and +5 V standby.
2. A boost regulated DC input for Main 300 VDC to 385 VDC
minimum nominal of 375 VDC.
3. HiperTFS total efficiency at least 85% at full load.
4. Schottky high-efficiency output diodes.
5. DC input for Standby 130 VDC to 385 VDC.
6. Sufficient heat sinking and fan cooling to keep device
temperature below 100 °C.
7. Transformer designed with nominal duty factor of 45%.
HiperTFS Selection
Selecting the optimum HiperTFS depends upon the continuous
output power, thermal management, (heat sinking, etc.), and
maximum ambient operating temperature. OEM applications
are typically 50 °C max ambient while clone PC supplies are
usually specified at 25 °C ambient. Higher efficiency can be
achieved with the larger devices. The maximum output power
can be tailored for any given device by programming primary
ILIMIT(MA).
Hold-Up Time
The input capacitor is a critical component in designing for a
guaranteed minimum hold-up time. Proper design of the
transformer’s nominal duty cycle and sufficient primary winding
clamp voltage for rest of Main transformer are also essential.
PIXLS (PI Expert Design Spreadsheet) can compute these
values or refer to formula in AN-51.
Bias Support for High-Side Driver
Bias support for HiperTFS high-side switch is sourced from a
forward phased winding of the Main transformer and should
provide a minimum of 17 V at 300 VDC input (or minimum input
voltage at which regulation can be maintained) to guarantee the
12 V bias required for the high-side driver is maintained.
Primary Bias Support
The standby converter provides a minimum 17 V output that
biases the BYPASS pin of HiperTFS. It is also the source for
remote ON/OFF control and OVP. This output should be
capable of delivering a minimum of 20 mA. The primary bias
filter capacitor should be at 330 mF to hold up the bias during
the start-up transient.
Start-Up
There is a duty factor soft-start function at start-up that slews
from 30% duty factor to max duty factor in approximately 15 ms.
The current limit during start-up is actually boosted by 115% for
the first 32 ms to provide the ability to drive heavy capacitive
loads and meet less than 20 ms output rise time requirement.
Figure 14. Full Range EMI Scan (132 kHz with Jitter) With Identical Circuitry and Conditions.
Figure 15. Typical Primary Winding Clamp-to-Rail.
-20
-10
0
-10
20
30
40
50
60
70
80
0.15 1 10 30
Frequency (MHz)
Amplitude (dBµV)
PI-2576-010600
EN55022B (QP)
EN55022B (AV)
EN55022B (QP)
EN55022B (AV)
-20
-10
0
-10
20
30
40
50
60
70
80
0.15 1 10 30
Frequency (MHz)
Amplitude (dBµV)
PI-5856-030810
HD
HS
D
G S
HiperTFS VDDH
R
DR1
150 V
+VBUS
RTN
DR2
L
FB
EN
BP
DSB
PI-5846-111810
CONTROL
Figure 13. Fixed Frequency Operation Without Jitter.
Rev. C 02/11
15
TFS757-764HG
www.powerint.com
EMI
The frequency jitter feature modulates the switching frequency
over a narrow band as a means to reduce conducted EMI
average and quasi-peaks associated with the harmonics of the
fundamental switching frequency. This is particularly beneficial
for average conduction mode where the sampling bandwidth is
narrow. The modulation rate is nominally 250 Hz which is high
enough to reduce EMI but low enough to have negligible effect
on output ripple (rejected by control loop).
Transformer Design
It is recommended that the transformer be designed for a
maximum flux density of 3000 Gauss during continuous
maximum output power and a maximum peak transient flux
density no greater than 4000 Gauss. The turns ratio should be
chosen for a nominal duty factor of 45% at 385 VDC input to
guarantee transformer reset with typical primary winding
clamp-to-rail (Figure 15). For nominal duty factor of higher value
it is recommend to refer to AN-51 and use PIXLS spreadsheet
for optimal transformer design. Typically the transformer should
have foil secondary windings for outputs above 10 amps. The
primary winding should be split primary type to keep leakage
inductance low.
Standby Mode Consumption
The HiperTFS standby converter is essentially a TinySwitch-III
controller which uses whole-cycle ON/OFF control. This has the
benefit of operating at a low average frequency at lighter loads
which increases efficiency and reducers no-load consumption.
Heat Sinking
The HiperTFS package is eSIP-16/12. There is a metal exposed
pad that provides a low thermal path to the heat sink for the
low-side power device and standby power device. There is also
Figure 16. HiperTFS Layout Considerations. Figure 17. HiperTFS Heat Sink Mounting.
HD
HS
D
G S
HiperTFS VDDH
To Bulk
Capacitor
R
L
FB
EN
BP
DSB
CONTROL
PI-5883-032410
an over-molded, electrically isolated section of the package
backside that provides isolation between the heat sink and the
internal high-side switch. Thermal heat sink compound, and a
mounting clip providing a minimum torque of 50 Newtons, are
required for good thermal performance. The heat sink
temperature behind device should not exceed 95 °C to avoid
activating the over-temperature shutdown of HiperTFS. Since
some of the HiperTFS pins are bent towards the heat sink, there
needs to be a minimum of 0.078 inches clearance between
heat sink and PC board.
Layout Considerations
Use a single point connection between, SOURCE pin, GROUND
pin and bypass capacitor. Typically the bypass capacitor is a
surface mount type and is located directly under the HiperTFS
package between the GROUND pin and the BYPASS pin.
The FEEDBACK pin and ENABLE pin along with the LINE-
SENSE and RESET pins should be kept away from noisy, high
voltage switching areas. If it is unavoidable to have long traces
connecting to FEEDBACK pins then route these traces close to
quiet, low impedance traces, that act as a Faraday shield. The
LINE-SENSE and RESET pins are associated with multiple
series resistor sections due to the high-voltage sensing. Make
sure the last resistor in series chain is SMD type and place it
very close to the pin. This will minimize the pick-up of noise.
The primary auxiliary bias output rectifier and filter should be
star referenced to bulk capacitor. Any Y capacitors referenced
to DC primary should also be tied to quiet nodes of bulk
capacitor negative or positive terminal.
PI-5882-111710
Minimum Clearance
is 0.078 inches
~50 Newtons
Rev. C 02/11
16
TFS757-764HG
www.powerint.com
Figure 18. High-Side Bias.
Figure 19. Latching Output OVP.
HD
HS
D
G S
HiperTFS VDDH
R
L
FB
EN
BP
DSB
CONTROL
PI-5881-082610
C3
C1
R1
VIN
VAUX
C2
CR1
Minimum Supply Current to
VDDH = 1 mA
Main Transformer
VHIGH_BIAS
Standby Transformer
VHIGH_BIAS_(MIN) = VAUX_(MIN) = 14 V
VHIGH_BIAS –VDDH
1 mA
R1_MAX =
HD
HS
D
G S
HiperTFS VDDH
R
L
FB
EN
BP
DSB
CONTROL
PI-5879-111710
G S
VBIAS
VOUT
R1
IC1
(CTR = 1)
V1
VOUT(OV) = (15 mA × R1) + V1 + 1
IOVP ≥ 15 mA
Rev. C 02/11
17
TFS757-764HG
www.powerint.com
Figure 20. Non-Latching Output OVP.
Figure 21. Remote ON and Standby Bias.
HD
HS
D
G S
HiperTFS VDDH
R
L
FB
EN
BP
DSB
CONTROL
PI-5878-111710
VOUT
V1
VOUT(OV) = V1 + 1 V
VIN
VBIAS
R1 ≤
R1
VAUX - VCE_OPTO
IL(MA_OVOFF)
R1 ≤ 12 V - 0.3 V
146 µA
HD
HS
D
G S
HiperTFS VDDH
R
L
FB
EN
BP
DSB
CONTROL
PI-5877-111710
Standby Out VBIAS
R3
10 kΩQ1
R4
1 kΩ
13 V
REM
R16 V
R2
IREMOTE_MIN = 1 mA
ISTANDBY_MIN = 900 µA
ION_MIN = 5 mA
VON
R1 = VON - 6.7 V
5 mA R2 = VAUX(MIN) - 6 V
900 µA
Remote ON
Rev. C 02/11
18
TFS757-764HG
www.powerint.com
Figure 22. Input OVP (Latching).
Figure 23. Non-latching Input OVP.
HD
HS
D
G S
HiperTFS VDDH
R
L
FB
EN
BP
DSB
CONTROL
PI-5875-111710
VBIAS
20 kΩ
100 kΩ
10 kΩ
R1
90 kΩ
VR1
(+12 V)
VIN
R2
3.9 MΩ
R1 + R2 = 4 MΩ
IL(OV) = VIN(OV)
R1 + R2
R1 = VR1 - 1.9 V
IL(OV)
HD
HS
D
G S
HiperTFS VDDH
R
L
FB
EN
BP
DSB
CONTROL
PI-5876-111710
VIN
VBIAS
R1
90 kΩ
VR1
(+12 V)
300 kΩ
10 kΩ
R2
3.9 MΩ
R1 + R2 = 4 MΩ
IL(OV) = VIN(OV)
R1 + R2
R1 = VR1 - 1.9 V
IL(OV)
100 kΩ
Q1
Rev. C 02/11
19
TFS757-764HG
www.powerint.com
Figure 24. Fast AC Reset of BP Latch.
Figure 25. L and R Pin Reset and Duty Limit Circuit.
HD
HS
D
G S
HiperTFS VDDH
R
L
FB
EN
BP
DSB
CONTROL
PI-5873-020411
R1R2
150 V
R1 = R2 = 4 MΩ
HD
HS
AC
Input
D
G S
HiperTFS VDDH
L
N
R
L
FB
EN
BP
DSB
CONTROL
PI-5874-111710
100 kΩ
Q1
Q2
0.1 µF
1 MΩ
6.8 MΩ
VBIAS
6.8 MΩ
1 MΩ
Rev. C 02/11
20
TFS757-764HG
www.powerint.com
Figure 26. L and R Pin Duty Limit With RL = 4 MW and RR = 4 MW.
Applications Example
High Efficiency +12 V, 25 A Main Output and +5 V 2.5 A
Standby Power Supply
The circuit in Figure 26 is an example of a design using HiperTFS
providing a 300 W +12 V output forward derived Main converter
and a 12 W +5 V Standby output from the flyback controller of
HiperTFS. The very high integration of two full converters within
a single package immediately shows the result of very low
external parts count for the entire design. Both the main
converter and the flyback section of HiperTFS are designed to
give very high-efficiency. The main converter takes advantage
of the ability to operate above 50% duty factor which lowers
RMS switch currents and allows using lower voltage more
efficient Schottky diodes on the output. The flyback section
uses Power Integrations TinySwitch technology which is often
used in designs that demand high-efficiency and low no-load
input power consumption.
The design in Figure 27 is intended to work with a PFC boost
front end that nominally provides a 385 VDC input. The main
converter will regulate to full load between 300 VDC and 385
VDC. This voltage range guarantees greater than 20 ms hold-up
time with C1 (270 mF).
The standby section is designed to operate whether the boost
PFC stage is on or off. The standby therefore is designed to
operate from 100 VDC to 385 VDC which covers the normal
universal input of 90 VAC to 265 VAC.
The start-up sequence is initiated with HiperTFS charging the
BYPASS pin capacitor via internal high-voltage current source.
Current limit selection then follows via FEEDBACK pin and
ENABLE pin resistors. The HiperTFS then senses the input
voltage via the LINE-SENSE pin resistor series chain R12, R13,
R35. When the input voltage reaches 100 V VDC the LINE-
SENSE pin UV standby threshold is reached and the standby
converter turns on. After several milliseconds the standby
output will reach regulation and the primary VON +12 V bias will
be stable. When the input bulk voltage reaches 315 VDC
which is the UV threshold for the main converter, the main
converter will initiate a turn on sequence once the remote-on
command from secondary is activated. The remote-on switch
(SW1) on the secondary-side for this particular design allows
the user to manually activate that main converter by turning on
the remote-on optocoupler. In actual PC designs the remote-
on would be controlled by a computer start-up command. This
optocoupler sources 5 mA into the BYPASS pin of the HiperTFS
which is the threshold current to start the turn on sequence for
PI-5880-111710
Regulation (FB)
duty cycle
Reset duty
clamp
Hard
limit
To VIN
To Clamp
Reset Circuit
Available
duty cycle range
Duty
Factor
60%
RLRR
45%
100 µA
(385 V)
75 µA
(300 V)
L Pin Current
(VIN with RL = 4 MΩ)
L and R Pin Transformer Reset and
Forward Duty Clamp Protection
R
L
HiperTFS
Forward duty
clamp
This region for
transient response
Rev. C 02/11
21
TFS757-764HG
www.powerint.com
Figure 27. Schematic of High-Efficiency +12 V, 25 A Main Output and +5 V, 2.5 A Standby Power Supply.
the Main converter. The Main converter will first turn on the
bottom switch to allow the high-side drive to receive the boot-
strap bias. After 14 ms the Main converter will start switching
both switches at 66 kHz and the main output voltage will rise.
Once the regulator U5 becomes active, current will flow through
the optocoupler U1. The collector of U1 will sink current out of
the FEEDBACK pin to adjust for appropriate duty cycle to
maintain regulation. The normal operating sink current is
between 1 mA and 2 mA. There is a forward phased bias
winding off the main transformer that provides sustained bias
for the high-side driver. During normal and brownout operation
the RESET pin senses the turn off clamp voltage via the resistor
chain R6, R18, R19 and the internal controller determines the
maximum safe duty factor by comparing the RESET pin current
with the LINE-SENSE pin current. This features guarantees that
saturation of the transformer is completely avoided in all conditions
including brownout and load transients. The LINE- SENSE pin
also has a UV low threshold which turns off the Main converter
when the input voltage is below 215 V.
This design in particular is intended to operate with a minimum
of 30 CFM airflow at full load.
Both the main and standby output have overvoltage protection
from sense circuit around U4 which will source >15 mA during
fault into bypass pin to cause latching shut-off of both converters.
The standby uses auto-restart to protect the standby output
from overpower and over-current. The main output is current
limited by the selected internal primary current limit of the main
switch path.
HD
14 - 25 V
D5
BAV20
VR4
MMSZ5243BT1G
13 V
D7
M6060C-E3/45
D6
M6060C-E3/45
D9
UF4005
C21
2.2 nF
L1
3.3 µH
C4
100 nF
C5
47 nF
C10
3300 µFC11
3300 µF
R21
2 kΩ
R28
100 Ω
R30
1 kΩ
R34
4.75 kΩ
R31
4.75 kΩ
U7
LM431
U5
LM431
R33
1 kΩ
R32
4.7 kΩ
SW1
Remote ON/OFF
U3A
PC817XI1J00F
R24
3.92 kΩ
R3
100 Ω
R4
150 Ω
RTN
5 V12 V
D2
U4A
PC817XI1JD0F
VR1
ZMM5242B-7
12 V
VR2
ZMM5230B-7
4.7 V
R15
750 Ω
U1A
PC817XI1J00F
R9
15 kΩ
R10
221 Ω
C9
1 nF
D8
UF4005
C19
1 nF
C20
330 µF
*Optional component for accidental reverse connection
R26
47 Ω
C17
2200 µFU2A
PC817XI1J00F
C14
470 nF
C16
330 nF
C15
2200 µF
C13
100 nF
U2B
PC817XI1J00F
U1B
PC817XI1J00F
R25
232 kΩ
R27
280 kΩ
D10
BAS16HT1G
J3-1
J4-1
J3-3
R14
2 kΩ
C6
100 nF
C3
100 nF
D3
1N4007
R5
4.7 Ω
R1
2.2 Ω
C1
270 µF
F2
4 A
D13*
1N5404
R20
4.7 kΩ
R16
7.5 kΩ
R17
820 Ω
R35
1.33 MΩ
R13
1.33 MΩ
R12
1.33 MΩ
R23
1 kΩ
R22
4.7 kΩ
U3B
PC817X1J00F
U4B
PC817X1J00F
R6
100 Ω
VR3
P6KE150A
R18
1.33 MΩ
R19
1.33 M
R36
1.33 MΩ
R8
4.7 Ω
U6
TFS762HG
D4
1N4007
D12
RGP100
D11
STPS1045B
3
5
2
1
2
6
9,10
9,10
13,14
1
HS
380 VDC
RTN
RTN
FB
EN
TSTANDBY
TMAIN
D
G S5 6
VDDH13
R
L
FB
BP
EN
7
9
10
11
8
DSB
16
14
1
3
PI-5969-102810
C12
1 µF
6,7
CONTROL
+12 V
+5 V
R29
470 Ω
L2
2.2 µH
R7
4.7 Ω
C18
1 nF
C2
3.3 nF
C8
100 nF
R11
43.2 kΩ
Q1
MMBT4401
Rev. C 02/11
22
TFS757-764HG
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Figure 28. Layout of High-Efficiency +12 V, 25 A Main Output and +5 V, 2.5 A Standby Power Supply.
+– HV
PI-5872-042710
Transformer
L1
D1
D7
VR1VR2
D6
C10+
D2SW1
R4
L2
R26
R29
VR4
R17
R22
C18
C20
J4
C7
C17
T2
U4
U2 U7
U3 R32
R33
C13
C8
C9
R11
C2
R10
C4
R24
R21
R15
D8
R12
R1
C2
D5
R14
R15
C12
R27
R34
R20
R16 D12
D10
R23
C16
R3
R31
R28
C14
R30
C15
C21
F1
J3
+ C1
C16
C3
C13
VR3
D3
TP1
R6
C11+
J1
R9
J2
R13
R18
R36
D4
R7 R8
R35 D9
C6
R25
Y Capacitor
HF LC
Post-Filter
5 V
+
–
12 V
+
–
Rev. C 02/11
23
TFS757-764HG
www.powerint.com
Parameter Symbol
Conditions
SOURCE = 0 V; TJ = 0 °C to 100 °C
(Unless Otherwise Specified)
Min Typ Max Units
Control Functions
Switching Frequency
- PC Main fS(MA) TJ = 25 °C Average 62 66 70 kHz
Peak-to-Peak Jitter 4
Frequency Jitter
Modulation Rate fM(MA) 250 Hz
Remote-ON Main
BYPASS Pin
Remote-ON Current IBP(ON) VEN = Open 3.2 3.8 4.4 mA
BYPASS Pin Remote-
OFF Current Hysteresis IBP(OFF) 1.1 mA
BYPASS Pin Latching
Shutdown Threshold IBP(SD) 13 15.5 17.5 mA
Main/Standby Remote-
ON Delay tR(ON) 2.5 ms
Main/Standby Remote-
OFF Delay tR(OFF) 2.5 ms
Main/Standby Remote-
OFF Long Time Period tR(PERIOD) 80 ms
Absolute Maximum Ratings(1,5)
DRAIN Voltage High-Side MOSFET .......................-0.3 V to 530 V
DRAIN Peak Current High-Side: TFS757 ................... 3.1 (5.9) 4 A
TFS758 ................... 4.5 (8.4)4 A
TFS759 ................... 5.0 (9.3)4 A
TFS760 ................. 5.7 (10.7)4 A
TFS761 .................. 6.1 (11.4)4 A
TFS762 .................. 6.4 (12.1) 4 A
TFS763 ................. 7. 2 (13 .4 ) 4 A
TFS764 ................. 8.3 (15.5)4 A
DRAIN Voltage Low-Side MOSFET .................... -0.3 V to 725 V
DRAIN Peak Current Low-Side: TFS757 ................... 3 .1 (5. 9)4 A
TFS758 ................... 4.5 (8.4)4 A
TFS759 ................... 5.0 (9.3)4 A
TFS760 ................. 5.7 (10.7)4 A
TFS761 .................. 6.1 (11.4)4 A
TFS762 .................. 6.4 (12.1) 4 A
TFS763 ................. 7. 2 (13 .4 ) 4 A
TFS764.................8.3 (15.5)4 A
DRAIN Voltage Standby MOSFET ...................... -0.3 V to 725 V
DRAIN Peak Current Standby MOSFET ................ 1.20 (2.25)4 A
Enable (EN) Pin Voltage ..................... ....................... -0.3 V to 9 V
Enable (EN) Pin Current ................. ................................. 100 mA
Feedback (FB) Pin Voltage ................. ...................... -0.3 V to 9 V
Feedback (FB) Current ................... ................................. 100 mA
Line Sense (L) Pin Voltage ............................................-0.3 V to 9 V
Line Sense (L) Pin Current ............................................ .......100 ma
Reset (R) Pin Voltage ..................... ........................... -0.3 V to 9 V
Reset (R) Pin Current ..................................... .................... 100 mA
Bypass Supply (BP) Pin Voltage ............................... -0.3 V to 9 V
Bypass Supply (BP) Pin Current ................................... ..... 100 mA
High Side (VDDH) Supply Pin Voltage ................. -0.3 V to 13.4 V
High Side (VDDH) Supply Pin Current ..................................50 mA
Storage Temperature ............................................ -65 °C to 150 °C
Operating Junction Temperature(2).......................-40 °C to 150 °C
Lead Temperature(3) ................................................................. 260 °C
Notes:
1. All voltages referenced to SOURCE, TJ = 25 °C.
2. Normally limited by internal circuitry.
3. 1/16 in. (1.59 mm) from case for 5 seconds.
4. The higher peak DRAIN current is allowed while the DRAIN
voltage is simultaneously less than 400 V.
5. Maximum ratings specified may be applied one at a time,
without causing permanent damage to the product.
Exposure to Absolute Rating conditions for extended periods
of time may affect product reliability.
Thermal Resistance
High-Side MOSFET (θJC) TFS757, TFS758 .................... 15 °C/W
TFS759, TFS760 .................... 14 °C/W
TFS761, TFS762 .................... 13 °C/W
TFS763, TFS764 .................... 12 °C/W
Low-Side MOSFET (θJC) ................................................ 1 °C/W
Notes:
1. All voltages referenced to SOURCE, TA = 25 °C.
Soft-Start
High-Side Start-Up
Charge Time tD(CH) 14 ms
Main Current Limit
at Start-Up ILIM(SS) See Note A 115 %
Soft-Start Period 12 ms
Rev. C 02/11
24
TFS757-764HG
www.powerint.com
Parameter Symbol
Conditions
SOURCE = 0 V; TJ = 0 °C to 100 °C
(Unless Otherwise Specified)
Min Typ Max Units
FEEDBACK Pin
PWM Gain DCREG(MA)
-1800 mA < IFB < -1500 mA, IL = 60 mA,
IR = 160 mA -70 %/mA
PWM Gain
Temperature Drift TCDCREG 0.05 %/°C
FEEDBACK Pin Feed-
back Onset current IFB(ON) IL = 60 mA, IR = 170 mA
TJ = 25 °C
-1.1 mA
FEEDBACK Pin Current
at Zero Duty Cycle IFB(OFF) -2.1 mA
FEEDBACK Pin
Internal Filter Pole PFB 12 kHz
FEEDBACK Pin Voltage VFB IFB (OFF), IFB = IFB(ON) 3.56 V
LINE-SENSE Pin (Line Voltage)
Line Undervoltage
Threshold – Standby
IL(SB-UVON) TJ = 25 °C Threshold 25
mA
IL(SB-UVOFF) 10
Line Undervoltage
Threshold – Main
IL(MA-UVON) TJ = 25 °C
Threshold 76 80 84
mA
IL(MA-UVOFF) Threshold 47 53 58
Line Overvoltage
Threshold – Main
and Standby
IL(MA-OVON) TJ = 25 °C
Threshold 119 135 146
mA
IL(MA-OVOFF) Threshold 135 146 164
LINE-SENSE Pin
Voltage VL
IL = 79 mA 2.4 V
IL = 149 mA 2.5
LINE-SENSE Pin
Short Circuit IL(SC) VL = VBP 375 mA
RESET Pin (Duty Limit/Main Only Remote-OFF)
Reset Overvoltage
Threshold
IR(MA-OVON) TJ = 25 °C
Threshold 165 205 245
mA
IR(MA-OVOFF) Threshold 175 215 255
RESET Pin Voltage VRIR = 155 mA 2.5 V
RESET Pin Short
Circuit Current IR(SC) VR = VBP 375 mA
Duty Cycle –
Programmable Limit
DCLIMIT(MA)
IL = 100 mA, IR = 110 mA50.5
%
IL = 115 mA, IR = 140 mA47.5
DCMAX(MA) IL = 100 mA, IR = 170 mA63
Current Limit Programming
FEEDBACK Pin
Current Limit
Detection Range #1
ILIM(1)(MA)
Start-up
See Note C 0-5 mA
FEEDBACK Pin
Current Limit
Detection Range #2
ILIM(2)(MA)
Start-up
See Note C 5-12 mA
FEEDBACK Pin
Current Limit
Detection Range #3
ILIM(3)(MA)
Start-up
See Note C 12-24 mA
Rev. C 02/11
25
TFS757-764HG
www.powerint.com
Parameter Symbol
Conditions
SOURCE = 0 V; TJ = 0 °C to 100 °C
(Unless Otherwise Specified)
Min Typ Max Units
Maximum Current Limit
Current Limit
ILIM(1)(MA) TFS757
TJ = 25 °C
di/dt = 175 mA/ms1.02
A
ILIM(2)(MA) di/dt = 233 mA/ms 1.36
ILIM(3)(MA) di/dt = 291 mA/ms 1.58 1.70 1.82
ILIM(1)(MA) TFS758
TJ = 25 °C
di/dt = 250 mA/ms 1.45
ILIM(2)(MA) di/dt = 335 mA/ms 1.95
ILIM(3)(MA) di/dt = 420 mA/ms 2.28 2.45 2.62
ILIM(1)(MA) TFS759
TJ = 25 °C
di/dt = 258 mA/ms 1.62
ILIM(2)(MA) di/dt = 344 mA/ms2.16
ILIM(3)(MA) di/dt = 430 mA/ms 2.55 2.70 2.94
ILIM(1)(MA) TFS760
TJ = 25 °C
di/dt = 324 mA/ms 1.86
ILIM(2)(MA) di/dt = 432 mA/ms 2.48
ILIM(3)(MA) di/dt = 540 mA/ms2.88 3.10 3.30
ILIM(1)(MA) TFS761
TJ = 25 °C
di/dt = 338 mA/ms 1.95
ILIM(2)(MA) di/dt = 450 mA/ms 2.65
ILIM(3)(MA) di/dt = 564 mA/ms 3.07 3.30 3.53
ILIM(1)(MA) TFS762
TJ = 25 °C
di/dt = 360 mA/ms2.10
ILIM(2)(MA) di/dt = 480 mA/ms 2.80
ILIM(3)(MA) di/dt = 600 mA/ms 3.25 3.50 3.75
ILIM(1)(MA) TFS763
TJ = 25 °C
di/dt = 402 mA/ms 2.35
ILIM(2)(MA) di/dt = 402 mA/ms 3.10
ILIM(3)(MA) di/dt = 670 mA/ms 3.60 3.90 4.16
ILIM(1)(MA) TFS764
TJ = 25 °C
di/dt = 468 mA/ms2.70
ILIM(2)(MA) di/dt = 624 mA/ms3.60
ILIM(3)(MA) di/dt = 780 mA/ms4.18 4.50 4.81
Low-Side Main MOSFET
ON-State
Resistance RDS(ON)
TFS757
ID = ILIM(3)(MA)
TJ = 25 °C 4.87 5.60
W
TJ = 100 °C 7.69 9.05
TFS758
ID = ILIM(3)(MA)
TJ = 25 °C 3.25 3.73
TJ = 100 °C 4.90 5.83
TFS759
ID = ILIM(3)(MA)
TJ = 25 °C 2.35 2.70
TJ = 100 °C 3.60 4.21
TFS760
ID = ILIM(3)(MA)
TJ = 25 °C 1.96 2.24
TJ = 100 °C 2.80 3.29
TFS761
ID = ILIM(3)(MA)
TJ = 25 °C 1.60 1.85
TJ = 100 °C 2.30 2.75
TFS762
ID = ILIM(3)(MA)
TJ = 25 °C 1.40 1.60
TJ = 100 °C 2.00 2.35
TFS763
ID = ILIM(3)(MA)
TJ = 25 °C 1.20 1.40
TJ = 100 °C 1.70 2.05
TFS764
ID = ILIM(3)(MA)
TJ = 25 °C 1.10 1.26
TJ = 100 °C 1.53 1.80
OFF-State Drain
Leakage Current IDSS(D)
TFS757
VL, VR = 0 V, IBP = 6 mA,
VDS = 560 V, TJ = 100 °C
150
mA
TFS758 150
TFS759 150
TFS760 150
TFS761 470
TFS762 470
Rev. C 02/11
26
TFS757-764HG
www.powerint.com
Parameter Symbol
Conditions
SOURCE = 0 V; TJ = 0 °C to 100 °C
(Unless Otherwise Specified)
Min Typ Max Units
Low-Side Main MOSFET (cont.)
OFF-State Drain
Leakage Current IDSS(D)
TFS763 VL, VR = 0 V, IBP = 6 mA,
VDS = 560 V, TJ = 100 °C
470 mA
TFS764 470
Breakdown
Voltage BVDSS(D)
VL, VR = 0 V, IBP = 6 mA,
TJ = 25 °C725 V
Rise Time tR(D) 100 ns
Fall Time tF(D) 50 ns
High-Side Main MOSFET
ON-State Resistance RDS(ON)(HD)
TFS757
ID = ILIM(3)(MA)
TJ = 25 °C 1.76
W
TJ = 100 °C 2.12
TFS758
ID = ILIM(3)(MA)
TJ = 25 °C 1.15
TJ = 100 °C 1.40
TFS759
ID = ILIM(3)(MA)
TJ = 25 °C 0.88
TJ = 100 °C 1.06
TFS760
ID = ILIM(3)(MA)
TJ = 25 °C 0.88
TJ = 100 °C 1.06
TFS761
ID = ILIM(3)(MA)
TJ = 25 °C 0.69
TJ = 100 °C 0.84
TFS762
ID = ILIM(3)(MA)
TJ = 25 °C 0.58
TJ = 100 °C 0.7
TFS763
ID = ILIM(3)(MA)
TJ = 25 °C 0.46
TJ = 100 °C 0.56
TFS764
ID = ILIM(3)(MA)
TJ = 25 °C 0.46
TJ = 100 °C 0.56
Effective Output
Capacitance COSS(EFF)(HD)
TFS757
TJ = 25 °C, VGS = 0 V
VDS = 0 V to 80% VDSS(HD)
55
pF
TFS758 82
TFS759 110
TFS760 110
TFS761 140
TFS762 165
TFS763 205
TFS764 205
Breakdown Voltage BVDSS(HD) TJ = 25 °C 530 V
OFF-State Drain
Current Leakage IDSS(HD)
TFS757
VD = 424 V,
TJ = 100 °C
60
mA
TFS758 60
TFS759 60
TFS760 60
TFS761 65
TFS762 80
TFS763 110
TFS764 110
Turn-on Voltage
Rise Time tR(HD) 30 ns
Turn-off Voltage
Fall Time tF(HD) 25 ns
Rev. C 02/11
27
TFS757-764HG
www.powerint.com
Parameter Symbol
Conditions
SOURCE = 0 V; TJ = 0 °C to 100 °C
(Unless Otherwise Specified)
Min Typ Max Units
High-Side Main MOSFET (cont.)
High-Side Bias
Shunt Voltage VDDH(SHUNT)
See Note B
IDDH = 2 mA 11.4 12.1 12.8 V
High-Side Undervoltage
ON-Threshold VDDH(UVON) See Note B 10.7 11.1 11.5 V
High-Side Undervoltage
OFF-Threshold VDDH(UVOFF) See Note B 9.5 9.9 10.3 V
High-Side Shunt
Hysteresis Voltage VDDH(HYST) See Note B 0.7 1.2 1.5 V
Standby MOSFET
ON-State
Resistance RDS(ON)(DS) IDSB = ILIM(3)(DSB)
TJ = 25 °C 3.7 4.37 W
TJ = 100 °C 5.5 6.25
OFF-State Drain
Leakage Current
IDSS1(DS)
VBP = 6.2 V
VEN = 0 V
VDS = 560 V
TJ = 100 °C
200
mA
IDSS2(DS)
VBP = 6.2 V
VEN = 0 V
VDS = 375 V,
TJ = 50 °C15
Breakdown Voltage BVDSS(DS)
VBP = 6.2 V, VEN = 0 V,
TJ = 25 °C725 V
DRAIN Supply Voltage VDSB(START) 50 V
Standby Controller
Output Frequency
in Standard Mode fS(SB) TJ = 25 °C Average 124 132 140 kHz
Peak-to-peak Jitter 8
Maximum Duty Cycle DCMAX(DSB) IL = 40 mA 67 70 73 %
ENABLE Pin Upper
Turnoff Threshold
Current
IDIS -150 -115 -80 mA
ENABLE Pin Voltage VEN
IEN = 25 mA 2.0 2.4 2.8 V
IEN = -25 mA 0.8 1.2 1.6
BYPASS Pin
Charge Current
ICH1
VBP = 0 V,
TJ = 25 °C -5 -3.2 -2
mA
ICH2
VBP = 4 V,
TJ = 25 °C -4 -1.5 0
BYPASS Pin Voltage VBP VDS = 50 V 5.50 5.70 5.90 V
BYPASS Pin Voltage
Hysteresis VBP(HYST) 0.80 1.0 1.20 V
BYPASS Pin Shunt
Voltage VBP(SHUNT) IBP = 2 mA 5.8 6.0 6.2 V
Standby Circuit Protection
ENABLE Pin Current
Limit Selection Range #1 ILIM(1)(DSB) Start-up 0-8.5 mA
Rev. C 02/11
28
TFS757-764HG
www.powerint.com
Parameter Symbol
Conditions
SOURCE = 0 V; TJ = 0 °C to 100 °C
(Unless Otherwise Specified)
Min Typ Max Units
Standby Circuit Protection (cont.)
ENABLE Pin Current
Limit Selection Range #2 ILIM(2)(DSB) Start-up 8.5-18 mA
ENABLE Pin Current
Limit Selection Range #3 ILIM(3)(DSB) Start-up 18-33 mA
ENABLE Pin Current
Limit Selection Range #4 ILIM(4)(DSB) Start-up 33-60 mA
Standby Current Limit
ILIM(1)(DSB) IL = 20 mA, di/dt = 95 mA/ms, TJ = 25 °C 450 500 550
mA
ILIM(2)(DSB) IL = 20 mA, di/dt = 125 mA/ms, TJ = 25 °C 600 650 700
ILIM(3)(DSB) IL = 20 mA, di/dt = 143 mA/ms, TJ = 25 °C 675 750 825
ILIM(4)(DSB) IL = 20 mA, di/dt = 105 mA/ms, TJ = 25 °C 495 550 605
Δ ILIM
ILIM (IL = 100 mA) / ILIM (IL = 20 mA)
di/dt = 125 mA/ms80 %
General Circuit Protection
Power Coefficient I2fI2f = ILIM(2)(DSB)(TYP)× fS(SB)(OSC)(TYP)
TJ = 25 °C0.9 × I2f I2f 1.12 × I2f A2Hz
Initial Current Limit IINIT TJ = 25 °C0.75 ×
ILIM(MIN)
Leading Edge
Blanking Time (Main) tLEB(D) TJ = 25 °C 170 215 ns
Leading Edge Blanking
Time (Standby) tLEB(DSB) TJ = 25 °C 170 215 ns
Current Limit
Delay (Main) tILD(D) TJ = 25 °C 150 ns
Current Limit
Delay (Standby) tILD(DSB) TJ = 25 °C 150 ns
Thermal Shutdown
Temperature TSD 118 °C
Thermal Shutdown
Hysteresis TSD(HYST) 55 °C
Auto-Restart ON-Time
at fOSC Standby tAR TJ = 25 °C 64 ms
Auto-Restart Duty
Cycle Standby DCAR TJ = 25 °C 2.2 %
Supply Current
DRAIN Supply Current
IS1
EN Current > IDIS
(No MOSFETs Switching) 400 750 1000
mA
IS2
EN Open (Standby MOSFET
Switching at fOSC)600 950 1200
NOTES:
A. The current limit is boosted for the first 34 ms of main supply switching and returns to normal level after this period.
B. VDDH(SHUNT) minus VDDH(UV_ON) is equal to 250 mV minimum.
C. Level 1 RFB = open, Level 2 RFB = 511 kW, Level 3 RFB = 232 kW.
D. Level 1 REN = open, Level 2 REN = 280 kW, Level 3 REN = 137 kW, Level 4 REN = 63.4 kW.
Rev. C 02/11
29
TFS757-764HG
www.powerint.com
1.2
1.0
0.8
0.6
0.4
0.2
0
-50 -25 0 25 50 75 100 125 150
Junction Temperature (°C)
PI-6003-060210
STANDBY DRAIN Pin Current Limit
(Normalized to 25 °C)
1.2
1.0
0.8
0.6
0.4
0.2
0
-50 -25 0 25 50 75 100 125 150
Junction Temperature (°C)
PI-6002-060210
MAIN DRAIN Pin Current Limit
(Normalized to 25 °C)
1.2
1.0
0.8
0.6
0.4
0.2
0
-50 -25 0 25 50 75 100 125
Junction Temperature (° C)
PI-6001-060210
STANDBY DRAIN Pin Output Frequency
(Normalized to 25 °C)
1.2
1.0
0.8
0.6
0.4
0.2
0
-50 -25 0 25 50 75 100 125 150
Junction Temperature (°C)
PI-6000-060210
MAIN DRAIN Pin Output Frequency
(Normalized to 25 °C)
1.1
1.0
0.9
-50 -25 0 25 50 75 100 125 150
Junction Temperature (°C)
STANDBY DRAIN Pin Breakdown Voltage
(Normalized to 25 °C)
PI-5999-060210
1.1
1.0
0.9
-50 -25 0 25 50 75 100 125 150
Junction Temperature (°C)
MAIN DRAIN Pin Breakdown Voltage
(Normalized to 25 °C)
PI-5998-060210
Typical Performance Characteristics
Figure 29. Main Supply. Breakdown Voltage vs. Temperature. Figure 30. Standby Supply. Breakdown vs. Temperature.
Figure 31. Main Supply. Frequency vs. Temperature.
Figure 32. Standby Supply. Frequency vs. Temperature.
Figure 33. Main Supply. Internal Current Limit vs. Temperature. Figure 34. Standby Supply. External Current Limit vs.
Temperature with RIL = 10.5 kW
Rev. C 02/11
30
TFS757-764HG
www.powerint.com
1.2
1.0
0.8
0.6
0.4
0.2
0
-50 -25 0 25 50 75 100 125
Junction Temperature (°C)
PI-5959-060210
STANDBY DRAIN Pin Undervoltage
Threshold (Normalized to 25 °C)
Typical Performance Characteristics (cont.)
Figure 36. L Pin Voltage vs. L Pin Current.
Figure 37. R Pin Voltage vs. R Pin Current. Figure 38. FEEDBACK Pin Current vs. FEEDBACK Pin Voltage.
Figure 39. ENABLE Pin Current vs. ENABLE Pin Voltage. Figure 40. BYPASS Pin Current vs. BYPASS Pin Voltage.
Figure 35. Standby Supply. Undervoltage Threshold vs.
Junction Temperature.
0
020 40 80 100 120 14060 160
L Pin Current (μA)
L Pin Voltage (V)
PI-5955-051210
4
2
3
1
5
0
050 150 200100 250
R Pin Current (μA)
R Pin Voltage (V)
PI-5954-050510
4
2
3
1
5
-5
FEEDBACK Pin Voltage (V)
FEEDBACK Pin Current (mA)
PI-5953-051210
0
-1
-2
-3
-4
1
0 1 2 3 4 5 76
-200
ENABLE Pin Voltage (V)
ENABLE Pin Current (µA)
PI-5952-051210
300
200
100
0
-100
500
400
0 1 2 3 4 5 76
0
0.0 2.0 4.0 6.0 8.0
BYPASS Pin Voltage (V)
BYPASS Pin Current (mA)
PI-5951-050510
20
10
30
Rev. C 02/11
31
TFS757-764HG
www.powerint.com
Typical Performance Characteristics (cont.)
0
04 8 12 16
VDDH Votage (V)
VDDH Current (mA)
PI-5950-012711
20
10
30
0
-50 -25 0 25 50 75 100 125
Temperature (°C)
Duty Cycle (%)
PI-5949-052510
50
75
25
100
0
-50 -25 0 25 50 75 100 125
Temperature (°C)
Duty Cycle (%)
PI-5948-052510
50
75
25
100
0
02 4 6 8 10 12 14 16 18 20
STANDBY DRAIN Voltage (V)
DRAIN Current (A)
PI-5942-060110
1
1.5
.5
TCASE = 25 °C
TCASE = 100 °C
2
2.5
5
0
02 4 6 8 10 12 14 16 18 20
DRAIN Voltage (V)
DRAIN Current (A)
PI-5943-091010
2
1
TCASE = 25 °C
TCASE = 100 °C
4
3
TFS757 0.4
TFS758 0.6
TFS759 0.8
TFS760 1.0
TFS761 1.2
TFS762 1.4
TFS763 1.6
TFS764 1.8
Scaling Factors:
0 100 200 300 400 500 600
0
10
100
1000
PI-5944-060110
STANDBY DRAIN Pin Voltage (V)
DRAIN Capacitance (pF)
Figure 41. VDDH Current vs. VDDH Voltage.
Figure 43. Duty Cycle vs. Temperature (IL = 115 mA, IR = 140 mA)
Figure 45. Drain Supply. Output Characteristics.
Figure 42. Duty Cycle vs. Temperature (TJ = 100 mA, JR = 110 mA).
Figure 44. Standby Supply. Output Characteristics.
Figure 46. Standby Supply. Drain Capacitance vs. Drain Voltage.
Rev. C 02/11
32
TFS757-764HG
www.powerint.com
Typical Performance Characteristics (cont.)
0 100 200 300 400 500 600
10
100
1000
10000
PI-5945-091010
DRAIN Pin Voltage (V)
DRAIN Capacitance (pF)
TFS757 0.4
TFS758 0.6
TFS759 0.8
TFS760 1.0
TFS761 1.2
TFS762 1.4
TFS763 1.6
TFS764 1.8
Scaling Factors:
250
200
100
100
150
0
0 200100 400 500 600300 700
STANDBY DRAIN Pin Voltage (V)
Power (mW)
PI-5946-060110
132 kHz
500
400
200
100
300
0
0 200100 400 500 600300 700
Power (mW)
PI-5947-091010
66 kHz
DRAIN Pin Voltage (V)
TFS757 0.4
TFS758 0.6
TFS759 0.8
TFS760 1.0
TFS761 1.2
TFS762 1.4
TFS763 1.6
TFS764 1.8
Scaling Factors:
Figure 47. Main Supply. Drain Capacitance vs. Drain Voltage. Figure 48. Standby Supply. Power vs. Drain Voltage.
Figure 49. Main Supply. Power vs. Drain Voltage. Figure 50. High-Side MOSFET Drain Current vs. Drain Voltage.
Figure 51. High-Side MOSFET Drain Current vs. Drain Voltage. Figure 52. High-Side MOSFET Breakdown Voltage vs. Temperature.
20
0
01 2 3 4 5 6 7
DRAIN Voltage (V)
DRAIN Current (A)
PI-5970-091010
5
15
10
25 °C 100 °C
TJ = 25 °C
TJ = 100 °C
TFS757 0.17
TFS758 0.25
TFS759/760 0.33
TFS761 0.42
TFS762 0.50
TFS763/764 0.63
Scaling Factors:
0 100 200 300 400
100
1000
PI-5971-083110
Drain Voltage (VHD-VHS)
COSS (pF)
TFS757 0.17
TFS758 0.25
TFS759/760 0.33
TFS761 0.42
TFS762 0.50
TFS763/764 0.63
Scaling Factors:
1.1
1.0
0.9
-50 -25 0 25 50 75 100 125 150
Temperature (°C)
Breakdown Voltage
(Normalized to 25 °C)
PI-5972-051210
Rev. C 02/11
33
TFS757-764HG
www.powerint.com
Typical Performance Characteristics (cont.)
2
1.5
1
0.5
0
0 100 200 300 400
DRAIN Voltage (VD)
Power (mW)
PI-5973-083110
TFS757 0.17
TFS758 0.25
TFS759/760 0.33
TFS761 0.42
TFS762 0.50
TFS763/764 0.63
Scaling Factors:
66 kHz
Figure 53. High-Side MOSFET Power vs. Drain Voltage.
Rev. C 02/11
34
TFS757-764HG
www.powerint.com
Pin 1
0.235 (5.96) Ref.
0.010 (0.25) Typ.
0.041 (1.04) Ref. 0.167 (4.24) Ref.
0.101 (2.57) Ref.
0.012 (0.30) Typ.
0.020 (0.51) Ref.
0.035 (0.89) Ref.
TOP-END VIEW B-B
Location of Exposed Metal Tie-Bars
PI-5300-021411
Notes:
1. Dimensioning and tolerancing per ASME Y14.5M-1994.
2. Dimensions noted are determined at the outermost extremesof the plastic body exclusive of mold flash, tie bar burrs, gate burrs, and inter-
lead flash, but including any mismatch between the top and bottom of the plastic body. Maximum mold protrusion is 0.007 (0.18) per side.
3. Dimensions noted are inclusive of plating thickness.
4. Does not include inter-lead flash or protrusions.
5. Pin #6 is the only straight (unformed) lead.
6. Controlling dimensions in inches (mm).
7 8. Tied to SOURCE (pin 6).
9. Tied to HS (pin 14).
10 11. Tied to HD (pin 16).
eSIP-16B (H Package)
0.381 (9.68)
Ref.
0.519 (13.18)
Ref.
0.012 (0.30) Ref.
0.628 (15.95) Ref.
0.019 (0.48) Ref.
0.027 (0.70)
0.023 (0.58)
0.020 (0.50)
0.060 (1.52) Ref. 10° Ref.
All Around
0.016 (0.41)
Ref.
0.290 (7.37)
Ref.
Detail A
0.076 (1.93)
0.118 (3.00)
0.038 (0.97) 0.056 (1.42) Ref.
16
13 141110
9 9
8
7
5 631
Pin 1 I.D.
0.118 (3.00)
0.201 (5.11)
Ref.
FRONT VIEW
SIDE VIEW BACK VIEW
Detail A (N.T.S)
BOTTOM-END VIEW
0.207 (5.26)
0.187 (4.75)
0.140 (3.56)
0.120 (3.05)
0.081 (2.06)
0.077 (1.96)
12×
0.024 (0.61)
0.019 (0.48)
0.010 M 0.25 M C A B
43
12×
0.016 (0.41)
0.011 (0.28)
0.020 M 0.51 M C
3
0.653 (16.59)
0.647 (16.43)
0.021 (0.53)
0.019 (0.48)
0.048 (1.22)
0.046 (1.17)
2
0.325 (8.25)
0.320 (8.13)
2
5
5
5
C
A
B
B B
MOUNTING HOLE PATTERN (N.T.S)
All dimensions in inches (mm)
0.152
(3.88)
5 1
0.164
(4.18)
6
0.114
(2.91)
791114
0.114
(2.91)
0.114
(2.91)
0.076
(1.94)
0.076
(1.94)
0.076
(1.94)
0.114
(2.91)
381016 13
16 1314 11 10 8756 3 1
8
9
10
11
7
Rev. C 02/11
35
TFS757-764HG
www.powerint.com
Part Marking Information
• HiperTFS Product Family
• TFS Series Number
• Package Identier
H Plastic eSIP-16B
• Pin Finish
G Halogen Free and RoHS Compliant
TFS 757 H G
Part Ordering Information
Part Number Option Quantity
PFS757HG Tube 30
PFS758HG Tube 30
PFS759HG Tube 30
PFS760HG Tube 30
PFS761HG Tube 30
PFS762HG Tube 30
PFS763HG Tube 30
PFS764HG Tube 30
Revision Notes Date
B Initial Release. 11/09/10
C Updated Absolute Maximum Ratings section. Updated TFS759 ILIMIT, Figures 3, 25, 41, and Package drawing. 02/11
For the latest updates, visit our website: www.powerint.com
Power Integrations reserves the right to make changes to its products at any time to improve reliability or manufacturability. Power
Integrations does not assume any liability arising from the use of any device or circuit described herein. POWER INTEGRATIONS MAKES
NO WARRANTY HEREIN AND SPECIFICALLY DISCLAIMS ALL WARRANTIES INCLUDING, WITHOUT LIMITATION, THE IMPLIED
WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT OF THIRD PARTY
RIGHTS.
Patent Information
The products and applications illustrated herein (including transformer construction and circuits external to the products) may be covered
by one or more U.S. and foreign patents, or Power Integrationslly by pending U.S. and foreign patent applications assigned to Power
Integrations. A complete list of Power Integrations patents may be found at www.powerint.com. Power Integrations grants its customers a
license under certain patent rights as set forth at http://www.powerint.com/ip.htm.
Life Support Policy
POWER INTEGRATIONS PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR
SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF POWER INTEGRATIONS. As used herein:
1. A Life support device or system is one which, (i) is intended for surgical implant into the body, or (ii) supports or sustains life, and (iii)
whose failure to perform, when properly used in accordance with instructions for use, can be reasonably expected to result in significant
injury or death to the user.
2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause
the failure of the life support device or system, or to affect its safety or effectiveness.
The PI logo, TOPSwitch, TinySwitch, LinkSwitch, DPA-Switch, PeakSwitch, CAPZero, SENZero, LinkZero, HiperPFS, HiperTFS, Qspeed,
EcoSmart, Clampless, E-Shield, Filterfuse, StakFET, PI Expert and PI FACTS are trademarks of Power Integrations, Inc. Other trademarks
are property of their respective companies. ©2011, Power Integrations, Inc.
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