03541 September 12, 2012 Rev: E
EP5358LUI/EP5358HUI
600mA Synchronous Buck Regulator
with Integrated Inductor
RoHS Compliant; Halogen Free
www.enpirion.com
Description
The EP5358xUI (x = L or H) is rated for up to
600mA of continuous output current. The
EP5358xUI integrates MOSFET switches,
control, compensation, and the magnetics in an
advanced 2.5mm x 2.25mm micro-QFN
Package.
Integrated magnetics enables a tiny solution
footprint, low output ripple, low part-count, and
high reliability, while maintaining high efficiency.
The complete solution can be implemented in as
little as 12mm2.
The EP5358xUI uses a 3-pin VID to easily select
the output voltage setting. Output voltage
settings are available in 2 optimized ranges
providing coverage for typical VOUT settings.
The VID pins can be changed on the fly for fast
dynamic voltage scaling. EP5358LUI further has
the option to use an external voltage divider.
The EP5358xUI is a perfect solution for noise
sensitive and space constrained applications that
require high efficiency.
EP5358xUI
2.2uF
10uF
4.75mm
2.25mm
Figure 1: Total Solution Footprint.
Features
Integrated Inductor Technology
2.5mm x 2.25mm x 1.1mm uQFN package
Total Solution Footprint 12mm2
Low VOUT ripple for RF compatibility
High efficiency, up to 93%
Up to 600mA continuous output current
Less than 1µA standby current
5 MHz switching frequency
3 pin VID for glitch free voltage scaling
V
OUT Range 0.6V to VIN – 0.25V
Short circuit and over current protection
UVLO and thermal protection
IC level reliability in a PowerSOC solution
Application
Wireless and RF applications
Wireless broad band data cards
Smart phone and portable media players
Advanced Low Power Processors, DSP, IO,
Memory, Video, Multimedia Engines
VOUT
2.2uF
PGND
EP5358HUI
ENABLE
PVIN
VS0
VS1
VS2
VSENSE
VOUT
10uF
AGND
AVIN
VIN
Figure 2: Typical Application Schematic
03541 September 12, 2012 Rev: E
EP5358LUI/EP5358HUI
©Enpirion 2012 all rights reserved, E&OE 2 www.enpirion.com
Ordering Information
Part Number Comment Package
EP5358LUI LOW VID Range 16-pin QFN T&R
EP5358HUI HIGH VID Range 16-pin QFN T&R
EP5358LUI-E EP5358LUI Evaluation Board
EP5358HUI-E EP5358HUI Evaluation Board
Pin Assignments (Top View)
PVIN
AVIN
ENABLE
VS0
VS1
VS2
NC(SW)
PGND
PGND
VFB
VSENSE
AGND
VOUT
VOUT
NC(SW)
NC(SW)
EP5358LUI
3
1
4
2
6
5
16 15
78
12
11
13
10
9
14
Figure 3: EP5358LUI Pin Out Diagram (Top View)
PVIN
AVIN
ENABLE
VS0
VS1
VS2
NC(SW)
PGND
PGND
NC
VSENSE
AGND
VOUT
VOUT
NC(SW)
NC(SW)
EP5358HUI
3
1
4
2
6
5
16 15
78
12
11
13
10
9
14
Figure 4: EP5358HUI Pin Out Diagram (Top View)
Pin Description
PIN NAME FUNCTION
1, 15,
16 NC(SW)
NO CONNECT – These pins are internally connected to the common switching node of the
internal MOSFETs. NC (SW) pins are not to be electrically connected to any external signal,
ground, or voltage. However, they must be soldered to the PCB. Failure to follow this
guideline may result in part malfunction or damage to the device.
2,3 PGND
Power ground. Connect these pins together and to the ground electrode of the Input and
output filter capacitors.
4 VFB/NC
EP5358LUI: Feed back pin for external divider option.
EP5358HUI: No Connect
5 VSENSE Sense pin for preset output voltages. Refer to application section for proper configuration.
6 AGND
Analog ground. This is the quiet ground for the internal control circuitry, and the ground
return for external feedback voltage divider
7, 8 VOUT Regulated Output Voltage. Refer to application section for proper layout and decoupling.
9, 10,
11
VS2, VS1,
VS0
Output voltage select. VS2 = pin 9, VS1 = pin 10, VS0 = pin 11.
EP5358LUI: Selects one of seven preset output voltages or an external resistor divider.
EP5358HUI: Selects one of eight preset output voltages.
(Refer to section on output voltage select for more details.)
12 ENABLE Output Enable. Enable = logic high; Disable = logic low
13 AVIN Input power supply for the controller circuitry.
14 PVIN Input Voltage for the MOSFET switches.
03541 September 12, 2012 Rev: E
EP5358LUI/EP5358HUI
©Enpirion 2012 all rights reserved, E&OE 3 www.enpirion.com
Absolute Maximum Ratings
CAUTION: Absolute Maximum ratings are stress ratings only. Functional operation beyond the
recommended operating conditions is not implied. Stress beyond the absolute maximum ratings may
cause permanent damage to the device. Exposure to absolute maximum rated conditions for
extended periods may affect device reliability.
PARAMETER SYMBOL MIN MAX UNITS
Input Supply Voltage VIN -0.3 6.0 V
Voltages on: ENABLE, VSENSE, VSO – VS2 -0.3 VIN+ 0.3 V
Voltages on: VFB (EP5358LUI) -0.3 2.7 V
Maximum Operating Junction Temperature TJ-ABS 150 °C
Storage Temperature Range TSTG -65 150 °C
Reflow Temp, 10 Sec, MSL3 JEDEC J-STD-020C 260 °C
ESD Rating (based on Human Body Mode) 2000 V
Recommended Operating Conditions
PARAMETER SYMBOL MIN MAX UNITS
Input Voltage Range VIN 2.4 5.5 V
Operating Ambient Temperature TA -40 +85 °C
Operating Junction Temperature TJ -40 +125 °C
Thermal Characteristics
PARAMETER SYMBOL TYP UNITS
Thermal Resistance: Junction to Ambient –0 LFM (Note 1) θJA 85 °C/W
Thermal Overload Trip Point TJ-TP +155 °C
Thermal Overload Trip Point Hysteresis 25 °C
Note 1: Based on a four layer copper board and proper thermal design per JEDEC EIJ/JESD51 standards
03541 September 12, 2012 Rev: E
EP5358LUI/EP5358HUI
©Enpirion 2012 all rights reserved, E&OE 4 www.enpirion.com
Electrical Characteristics
NOTE: TA = -40°C to +85°C unless otherwise noted. Typical values are at TA = 25°C, VIN = 3.6V.
CIN = 4.7µF MLCC, COUT = 10µF
PARAMETER SYMBOL TEST CONDITIONS MIN TYP MAX UNITS
Operating Input Voltage
Range VIN 2.4 5.5 V
Under Voltage Lock-out –
VIN Rising VUVLO_R 2.0 V
Under Voltage Lock-out –
VIN Falling VUVLO_F 1.9 V
Drop Out Resistance RDO Input to Output Resistance in 100%
duty cycle operation. 350 500 m
Output Voltage Range VOUT EP5358LUI (VDO = ILOAD X RDO)
EP5358HUI
0.6
1.8 VIN-VDO
3.3 V
Dynamic Voltage Slew
Rate (VID Change) VSLEW EP5358LUI
EP5358HUI 4
8 V/mS
VID Preset VOUT Initial
Accuracy ΔVOUT
TA = 25°C, VIN = 3.6V;
ILOAD = 100mA ;
0.8V VOUT 3.3V
-2 +2 %
Line Regulation ΔVOUT_LINE 2.4V VIN 5.5V 0.03 %/V
Load Regulation ΔVOUT_LOAD 0A ILOAD 600mA 0.48 %/A
Temperature Variation ΔVOUT_TEMPL -40°C TA +85°C 24
ppm/°C
Output Current IOUT 600 mA
Shut-down Current ISD Enable = Low 0.75 µA
OCP Threshold ILIM 2.4V VIN 5.5V
0.6V VOUT 3.3V 1.25 1.4 A
Feedback Pin Voltage
Initial Accuracy VFB
TA = 25°C, VIN = 3.6V;
ILOAD = 100mA ;
0.8V VOUT 3.3V
.588 0.6 0.612 V
Feedback Pin Input
Current IFB Note 1 <100 nA
VS0-VS2, Pin Logic Low VVSLO 0.0 0.3 V
VS0-VS2, Pin Logic High VVSHI 1.4
VIN V
VS0-VS2, Pin Input
Current IVSX Note 1 <100 nA
Enable Pin Logic Low VENLO 0.3 V
Enable Pin Logic High VENHI 1.4 V
Enable Pin Current IENABLE Note 1 <100 nA
Operating Frequency FOSC 5 MHz
Soft Start Operation
Soft Start Slew Rate ΔVSS EP5358LUI (VID MODE)
EP5358HUI (VID MODE)
2.6
5.2
4
8
5.4
10.8 V/mS
VOUT Rise Time TRISE EP53A8LUI VFB MODE 146 225 304 uSec
Note 1: Parameter guaranteed by design
03541 September 12, 2012 Rev: E
EP5358LUI/EP5358HUI
©Enpirion 2012 all rights reserved, E&OE 5 www.enpirion.com
Typical Performance Characteristics
45
50
55
60
65
70
75
80
85
90
95
0 200 400 600
Load Current (mA)
Efficiency (%)
Efficiency vs. Load Current: VIN = 5.0V, VOUT (from
top to bottom) = 3.3, 2.5, 1.8, 1.2V
45
50
55
60
65
70
75
80
85
90
95
0 200 400 600
Load Current (mA)
Eff ici ency (%)
Efficiency vs. Load Current: VIN = 3.7V, VOUT (from
top to bottom) = 2.5, 1.8, 1.2V
45
50
55
60
65
70
75
80
85
90
95
0 200 400 600
Load Current (mA)
Eff ici ency (%)
Efficiency vs. Load Current: VIN = 3.3V, VOUT (from
top to bottom) = 2.5, 1.8, 1.2V
Start Up Waveform: VIN = 5.0V, VOUT = 3.3V;
ILOAD = 10mA (VID MODE)
Start Up Waveform: VIN = 5.0V, VOUT = 3.3V;
ILOAD = 500mA (VID MODE)
03541 September 12, 2012 Rev: E
EP5358LUI/EP5358HUI
©Enpirion 2012 all rights reserved, E&OE 6 www.enpirion.com
Shut-do wn Waveform: VIN = 5.0V, VOUT = 3.3V;
ILOAD = 10mA
Shut-do wn Waveform: VIN = 5.0V, VOUT = 3.3V;
ILOAD = 500mA
Output Ripple: VIN = 5.0V, VOUT = 1.2V,
Load = 500mA
Output Ripple: VIN = 5.0V, VOUT = 3.3V
Load = 500mA
Output Ripple: VIN = 3.3V, VOUT = 1.8V
Load = 500mA Output Ripple: VIN = 3.3V, VOUT = 1.2V,
Load = 500mA
03541 September 12, 2012 Rev: E
EP5358LUI/EP5358HUI
©Enpirion 2012 all rights reserved, E&OE 7 www.enpirion.com
Load Transient: VIN = 5.0V, VOUT = 1.2V
Load stepped from 10mA to 500mA
Load Transient: VIN = 3.3V, VOUT = 1.8V
Load stepped from 10mA to 500mA
03541 September 12, 2012 Rev: E
EP5358LUI/EP5358HUI
©Enpirion 2012 all rights reserved, E&OE 8 www.enpirion.com
Functional Block Diagram
PVIN
ENABLE NC(SW)
VSENSE
VS0 VS1 VS2AVIN AGND
Voltage
Select
DAC
Switch
VREF
(+)
(-)
Error
Amp VFB
VOUT
Package Boundry
P-Drive
N-Drive
UVLO
Thermal Limit
Current Limit
Soft Start
Sawtooth
Generator
(+)
(-)
PWM
Comp
GND
Logic
Compensation
Network
EP5358UI
Figure 5: Functional Block Diagram
03541 September 12, 2012 Rev: E
EP5358LUI/EP5358HUI
©Enpirion 2012 all rights reserved, E&OE 9 www.enpirion.com
Detailed Description
Functional Overview
The EP5358xUI requires only 2 small MLCC
capacitors for a complete DC-DC converter
solution. The device integrates MOSFET
switches, PWM controller, Gate-drive,
compensation, and inductor into a tiny 2.5mm x
2.25mm x 1.1mm micro-QFN package.
Advanced package design, along with the high
level of integration, provides very low output
ripple and noise. The EP5358xUI uses voltage
mode control for high noise immunity and load
matching to advanced 90nm loads. A 3-pin
VID allows the user to choose from one of 8
output voltage settings. The EP5358xUI
comes with two VID output voltage ranges.
The EP5358HUI provides VOUT settings from
1.8V to 3.3V, the EP5358LUI provides VID
settings from 0.8V to 1.5V, and also has an
external resistor divider option to program
output setting over the 0.6V to VIN-0.25V
range. The EP5358xUI provides the industry’s
highest power density of any 600mA DCDC
converter solution.
The key enabler of this revolutionary
integration is Enpirion’s proprietary power
MOSFET technology. The advanced MOSFET
switches are implemented in deep-submicron
CMOS to supply very low switching loss at high
switching frequencies and to allow a high level
of integration. The semiconductor process
allows seem-less integration of all switching,
control, and compensation circuitry.
The proprietary magnetics design provides
high-density/high-value magnetics in a very
small footprint. Enpirion magnetics are
carefully matched to the control and
compensation circuitry yielding an optimal
solution with assured performance over the
entire operating range.
Protection features include under-voltage lock-
out (UVLO), over-current protection (OCP),
short circuit protection, and thermal overload
protection.
Integrated Inductor: Low-Noise Low-EMI
The EP5358xUI utilizes a proprietary low loss
integrated inductor. The integration of the
inductor greatly simplifies the power supply
design process. The inherent shielding and
compact construction of the integrated inductor
reduces the conducted and radiated noise that
can couple into the traces of the printed circuit
board. Further, the package layout is
optimized to reduce the electrical path length
for the high di/dT input AC ripple currents that
are a major source of radiated emissions from
DC-DC converters. The integrated inductor
provides the optimal solution to the complexity,
output ripple, and noise that plague low power
DCDC converter design.
Control Matched to sub 90nm Loads
The EP5358xUI utilizes an integrated type III
compensation network. Voltage mode control
is inherently impedance matched to the sub
90nm process technology that is used in
today’s advanced ICs. Voltage mode control
also provides a high degree of noise immunity
at light load currents so that low ripple and high
accuracy are maintained over the entire load
range. The very high switching frequency
allows for a very wide control loop bandwidth
and hence excellent transient performance.
Soft Start
Internal soft start circuits limit in-rush current
when the device starts up from a power down
condition or when the “ENABLE” pin is
asserted “high”. Digital control circuitry limits
the VOUT ramp rate to levels that are safe for
the Power MOSFETS and the integrated
inductor.
The EP5358HUI has a soft-start slew rate that
is twice that of the EP5358LUI.
When the EP5358LUI is configured in external
resistor divider mode, the device has a fixed
VOUT ramp time. Therefore, the ramp rate will
vary with the output voltage setting. Output
voltage ramp time is given in the Electrical
Characteristics Table.
03541 September 12, 2012 Rev: E
EP5358LUI/EP5358HUI
©Enpirion 2012 all rights reserved, E&OE 10 www.enpirion.com
Excess bulk capacitance on the output of the
device can cause an over-current condition at
startup. The maximum total capacitance on
the output, including the output filter capacitor
and bulk and decoupling capacitance, at the
load, is given as:
EP5358LUI:
COUT_TOTAL_MAX = COUT_Filter + COUT_BULK = 230uF
EP5358HUI:
COUT_TOTAL_MAX = COUT_Filter + COUT_BULK = 115uF
EP5358LUI in external divider mode:
COUT_TOTAL_MAX = 2.086x10-4/VOUT Farads
The above numbers and formula assume a no
load condition.
Over Current/Short Circuit Protection
The current limit function is achieved by
sensing the current flowing through a sense P-
MOSFET which is compared to a reference
current. When this level is exceeded the P-
FET is turned off and the N-FET is turned on,
pulling VOUT low. This condition is maintained
for approximately 0.5mS and then a normal
soft start is initiated. If the over current
condition still persists, this cycle will repeat.
Under Voltage Lockout
During initial power up an under voltage
lockout circuit will hold-off the switching
circuitry until the input voltage reaches a
sufficient level to insure proper operation. If
the voltage drops below the UVLO threshold
the lockout circuitry will again disable the
switching. Hysteresis is included to prevent
chattering between states.
Enable
The ENABLE pin provides a means to shut
down the converter or enable normal
operation. A logic low will disable the
converter and cause it to shut down. A logic
high will enable the converter into normal
operation.
NOTE: The ENABLE pin must not be left
floating.
Thermal Shutdown
When excessive power is dissipated in the
chip, the junction temperature rises. Once the
junction temperature exceeds the thermal
shutdown temperature the thermal shutdown
circuit turns off the converter output voltage
thus allowing the device to cool. When the
junction temperature decreases by 15C°, the
device will go through the normal startup
process.
03541 September 12, 2012 Rev: E
EP5358LUI/EP5358HUI
©Enpirion 2012 all rights reserved, E&OE 11 www.enpirion.com
Application Information
VIN VSENSE
PVIN
VS1
VS2
VS0
10μF
4.7μF
VOUT
VOUT
AGND
ENABLE
PGND
AVIN
Figure 6: Application Circuit, EP5358HUI,.
VIN VSENSE
PVIN
VS1
VS2
VS0
10μF
4.7μF
VOUT
VOUT
AGND
ENABLE
VFB
PGND
AVIN
Figure 7: Application Circuit, EP5358LUI, showing
the VFB function.
Output Voltage Programming
The EP5358xUI utilizes a 3-pin VID to program
the output voltage value. The VID is available
in two sets of output VID programming ranges.
The VID pins should be connected either to
AVIN or to AGND to avoid noise coupling into
the device.
The “Low” range is optimized for low voltage
applications. It comes with preset VID settings
ranging from 0.80V and 1.5V. This VID set
also has an external divider option.
To specify this VID range, order part number
EP5358LUI.
The “High” VID set provides output voltage
settings ranging from 1.8V to 3.3V. This
version does not have an external divider
option. To specify this VID range, order part
number EP5358HUI.
Internally, the output of the VID multiplexer
sets the value for the voltage reference DAC,
which in turn is connected to the non-inverting
input of the error amplifier. This allows the use
of a single feedback divider with constant loop
gain and optimum compensation, independent
of the output voltage selected.
NOTE: The VID pins must not be left floating.
EP5358L Low VID Range Programming
The EP5358LUI is designed to provide a high
degree of flexibility in powering applications
that require low VOUT settings and dynamic
voltage scaling (DVS). The device employs a
3-pin VID architecture that allows the user to
choose one of seven (7) preset output voltage
settings, or the user can select an external
voltage divider option. The VID pin settings
can be changed on the fly to implement glitch-
free voltage scaling.
Table 1: EP5358LUI VID Voltage Select Settings
V
S2
V
S1
V
S0
V
OUT
0001.50
0011.45
0101.20
0111.15
1001.10
1011.05
1100.8
111EXT
Table 1 shows the VS2-VS0 pin logic states for
the EP5358LUI and the associated output
voltage levels. A logic “1” indicates a
connection to AVIN or to a “high” logic voltage
level. A logic “0” indicates a connection to
AGND or to a “low” logic voltage level. These
pins can be either hardwired to AVIN or AGND
or alternatively can be driven by standard logic
levels. Logic levels are defined in the electrical
characteristics table. Any level between the
logic high and logic low is indeterminate.
EP5358LUI External Voltage Divider
The external divider option is chosen by
connecting VID pins VS2-VS0 to VIN or a logic
“1” or “high”. The EP5358LUI uses a separate
feedback pin, VFB, when using the external
divider. VSENSE must be connected to VOUT as
indicated in figure 8.
03541 September 12, 2012 Rev: E
EP5358LUI/EP5358HUI
©Enpirion 2012 all rights reserved, E&OE 12 www.enpirion.com
VIN VSENSE
VSO
VS2
EP5358LUI
10μF
4.7uF
VOUT
VOUT
AGND
ENABLE Ra
Rb
VFB
VS1
PGND
AVIN
PVIN
Figure 8: EP5358LUI using external divider
The output voltage is selected by the following
formula:
()
Rb
Ra
OUT VV += 16.0
Ra must be chosen as 237K to maintain loop
gain. Then Rb is given as:
Ω
=6.0
102.142 3
OUT
bVx
R
VOUT can be programmed over the range of
0.6V to (VIN – 0.25V).
NOTE: Dynamic Voltage Scaling is not allowed
between internal preset voltages and external
divider.
EP5358HUI High VID Range Programming
The EP5358HUI VOUT settings are optimized
for higher nominal voltages such as those
required to power IO, RF, or IC memory. The
preset voltages range from 1.8V to 3.3V.
There are eight (8) preset output voltage
settings. The EP5358HUI does not have an
external divider option. As with the
EP5358LUI, the VID pin settings can be
changed while the device is enabled.
Table 2 shows the VS0-VS2 pin logic states for
the EP5358HUI and the associated output
voltage levels. A logic “1” indicates a
connection to AVIN or to a “high” logic voltage
level. A logic “0” indicates a connection to
AGND or to a “low” logic voltage level. These
pins can be either hardwired to AVIN or AGND
or alternatively can be driven by standard logic
levels. Logic levels are defined in the electrical
characteristics table. Any level between the
logic high and logic low is indeterminate.
These pins must not be left floating.
Table 2: EP5358HUI VID Voltage Select Settings
V
S2
V
S1
V
S0
V
OUT
0003.3
0013.0
0102.9
0112.6
1002.5
1012.2
1102.1
1111.8
Custom VID Setting Adjustment
AVIN
PVIN
ENABLE
VSENSE
VOUT
AGND
PGND
5.0pF
Rs
10uF
4.7uF EP5358xUI
VS2
VS1
VSO
Figure 9: EP5358xUI with RC inserted in VSENSE
path to modify VID output voltages.
It is possible to adjust VOUT for a given VID
setting by inserting a parallel RC combination
in the VSENSE path as shown in figure 9. The
capacitor value is 5.0pF to ensure stability.
Note that the value of VOUT can only be
increased from its nominal setting
(VOUTNEW>VOUTOLD):
For EP5358LUI:
kOhms
VOUT
VOUT
Rs
OLD
NEW
L
= 1*711
For EP5358HUI:
kOhms
VOUT
VOUT
Rs
OLD
NEW
H
= 1*356
VOUTNEW is the desired “new” VOUT.
VOUTOLD is the VID table output voltage.
03541 September 12, 2012 Rev: E
EP5358LUI/EP5358HUI
©Enpirion 2012 all rights reserved, E&OE 13 www.enpirion.com
For a given Rs Value, the VOUTNEW for VID
settings is determined by the following
equations:
EP5358LUI:
Volts
Rs
VOUTVOUT L
OLDNEW
+
=1
711
EP5358HUI:
Volts
Rs
VOUTVOUT H
OLDNEW
+
=1
356
NOTE: The amount of adjustment is limited to
approximately 15% of the nominal VID setting.
NOTE: Adjusting VOUT using this method will
increase the tolerance of the output voltage.
The larger the adjustment, the greater the
increase in tolerance.
Power-Up/Down Sequencing
During power-up, ENABLE should not be
asserted before PVIN, and PVIN should not be
asserted before AVIN. The PVIN should never
be powered when AVIN is off. During power
down, the AVIN should not be powered down
before the PVIN. Tying PVIN and AVIN or all
three pins (AVIN, PVIN, ENABLE) together
during power up or power down meets these
requirements.
Pre-Bias Start-up
The EP5358xUI does not support startup into a
pre-biased condition. Be sure the output
capacitors are not charged or the output of the
EP5358xUI is not pre-biased when the
EP5358xUI is first enabled.
Input Filter Capacitor
For ILOAD 500mA, CIN = 2.2uF
For ILOAD > 500mA CIN = 4.7uF.
0402 capacitor case size is acceptable.
The input capacitor must use a X5R or X7R or
equivalent dielectric formulation. Y5V or
equivalent dielectric formulations lose
capacitance with frequency, bias, and with
temperature, and are not suitable for switch-
mode DC-DC converter input filter applications.
Output Filter Capacitor
For VIN 4.3V, COUT_MIN = 10uF 0603 MLCC.
For VIN > 4.3V, COUT_MIN = 10uF 0805 MLCC.
Ripple performance can be improved by using
2x10µF 0603 MLCC capacitors (for any
allowed VIN).
The maximum output filter capacitance next to
the output pins of the device is 60µF low ESR
MLCC capacitance. VOUT has to be sensed at
the last output filter capacitor next to the
EP5358xUI.
Additional bulk capacitance for decoupling and
bypass can be placed at the load as long as
there is sufficient separation between the VOUT
Sense point and the bulk capacitance.
Excess total capacitance on the output (Output
Filter + Bulk) can cause an over-current
condition at startup. Refer to the section on
Soft-Start for the maximum total capacitance
on the output.
The output capacitor must use a X5R or X7R
or equivalent dielectric formulation. Y5V or
equivalent dielectric formulations lose
capacitance with frequency, bias, and
temperature and are not suitable for switch-
mode DC-DC converter output filter
applications.
03541 September 12, 2012 Rev: E
EP5358LUI/EP5358HUI
©Enpirion 2012 all rights reserved, E&OE 14 www.enpirion.com
Recommended PCB Footprint
Figure 10: EP5358xUI Package PCB Footprint
03541 September 12, 2012 Rev: E
EP5358LUI/EP5358HUI
©Enpirion 2012 all rights reserved, E&OE 15 www.enpirion.com
Package and Mechanical
Figure 11: EN5358xUI Package Dime nsions
03541 September 12, 2012 Rev: E
EP5358LUI/EP5358HUI
©Enpirion 2012 all rights reserved, E&OE 16 www.enpirion.com
Contact Information
Enpirion, Inc.
Perryville III
53 Frontage Road Suite 210
Hampton, NJ 08827
Phone: +1 908-894-6000
Fax: +1 908-894-6090
Enpirion reserves the right to make changes in circuit design and/or specifications at any time without notice. Information furnished by Enpirion is
believed to be accurate and reliable. Enpirion assumes no responsibility for its use or for infringement of patents or other third party rights, which may
result from its use. Enpirion products are not authorized for use in nuclear control systems, as critical components in life support systems or equipment
used in hazardous environment without the express written authority from Enpirion.