EN
SS
HG
SW L
LM3150
FB
VCC
PGND
SGND
BST
ILIM
LG
CIN
CSS
VIN VIN
RON
RON
COUT
VOUT
CBST
CVCC VIN
RLIM RFB2
RFB1
M2
M1
LM3150
www.ti.com
SNVS561D SEPTEMBER 2008REVISED MARCH 2011
LM3150 SIMPLE SWITCHER
®
CONTROLLER, 42V Synchronous Step-Down
Check for Samples: LM3150
1FEATURES DESCRIPTION
The LM3150 SIMPLE SWITCHER®Controller is an
2 PowerWise®Step-down Controller easy to use and simplified step down power controller
6V to 42V Wide Input Voltage Range capable of providing up to 12A of output current in a
Adjustable Output Voltage Down to 0.6V typical application. Operating with an input voltage
range of 6V-42V, the LM3150 features an adjustable
Programmable Switching Frequency up to 1 output voltage down to 0.6V. The switching frequency
MHz is adjustable up to 1 MHz and the synchronous
No Loop Compensation Required architecture provides for highly efficient designs. The
Fully WEBENCH®Enabled LM3150 controller employs a Constant On-Time
(COT) architecture with a proprietary Emulated Ripple
Low External Component Count Mode (ERM) control that allows for the use of low
Constant On-Time Control ESR output capacitors, which reduces overall solution
Ultra-fast Transient Response size and output voltage ripple. The Constant On-Time
(COT) regulation architecture allows for fast transient
Stable with Low ESR Capacitors response and requires no loop compensation, which
Output Voltage Pre-bias Startup reduces external component count and reduces
Valley Current Limit design complexity.
Programmable Soft-start Fault protection features such as thermal shutdown,
under-voltage lockout, over-voltage protection, short-
TYPICAL APPLICATIONS circuit protection, current limit, and output voltage pre-
bias startup allow for a reliable and robust solution.
Telecom
Networking Equipment The LM3150 SIMPLE SWITCHER®concept provides
for an easy to use complete design using a minimum
Routers number of external components and TI’s WEBENCH®
Security Surveillance online design tool. WEBENCH®provides design
Power Modules support for every step of the design process and
includes features such as external component
calculation with a new MOSFET selector, electrical
simulation, thermal simulation, and Build-It boards for
prototyping.
Typical Application
1Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
2All trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date. Copyright © 2008–2011, Texas Instruments Incorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
1
2
3
411
12
13
14
HG
VCC
5
6
7
SGND
PGND
8
9
SS
RON
LG
EN
10
SW
FB
SGND
ILIM
BST
VIN
EP
LM3150
SNVS561D SEPTEMBER 2008REVISED MARCH 2011
www.ti.com
Connection Diagram
Figure 1. TSSOP-14
PIN DESCRIPTIONS
Pin Name Description Function
Supply Voltage for FET Nominally regulated to 5.95V. Connect a 1.0 µF to 4.7 µF decoupling capacitor from
1 VCC Drivers this pin to ground.
2 VIN Input Supply Voltage Supply pin to the device. Nominal input range is 6V to 42V.
To enable the IC apply a logic high signal to this pin greater than 1.26V typical or leave
3 EN Enable floating. To disable the part, ground the EN pin.
Internally connected to the regulation, over-voltage, and short-circuit comparators. The
4 FB Feedback regulation setting is 0.6V at this pin. Connect to feedback resistor divider between the
output and ground to set the output voltage.
Ground for all internal bias and reference circuitry. Should be connected to PGND at a
5,9 SGND Signal Ground single point.
An internal 7.7 µA current source charges an external capacitor to provide the soft-start
6 SS Soft-Start function.
7 RON On-time Control An external resistor from VIN to this pin sets the high-side switch on-time.
Monitors current through the low-side switch and triggers current limit operation if the
8 ILIM Current Limit inductor valley current exceeds a user defined value that is set by RLIM and the Sense
current, ILIM-TH, sourced out of this pin during operation.
Switch pin of controller and high-gate driver lower supply rail. A boost capacitor is also
10 SW Switch Node connected between this pin and BST pin
Gate drive signal to the high-side NMOS switch. The high-side gate driver voltage is
11 HG High-Side Gate Drive supplied by the differential voltage between the BST pin and SW pin.
High-gate driver upper supply rail. Connect a 0.33 µF-0.47 µF capacitor from SW pin to
Connection for Bootstrap
12 BST this pin. An internal diode charges the capacitor during the high-side switch off-time. Do
Capacitor not connect to an external supply rail.
Gate drive signal to the low-side NMOS switch. The low-side gate driver voltage is
13 LG Low-Side Gate Drive supplied by VCC.
Synchronous rectifier MOSFET source connection. Tie to power ground plane. Should
14 PGND Power Ground be tied to SGND at a single point.
Exposed die attach pad should be connected directly to SGND. Also used to help
EP EP Exposed Pad dissipate heat out of the IC.
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
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SNVS561D SEPTEMBER 2008REVISED MARCH 2011
Absolute Maximum Ratings(1)(2)
VIN, RON to GND -0.3V to 47V
SW to GND -3V to 47V
BST to SW -0.3V to 7V
BST to GND -0.3V to 52V
All Other Inputs to GND -0.3V to 7V
ESD Rating(3) 2 kV
Storage Temperature Range -65°C to +150°C
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is intended to be functional, but does not ensure specific performance limits. For ensured specifications and conditions,
see the Electrical Characteristics.
(2) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for availability and
specifications.
(3) The human body model is a 100 pF capacitor discharged through a 1.5 kresistor into each pin. Test Method is per JESD-22-A114.
Operating Ratings(1)
VIN 6V to 42V
Junction Temperature Range (TJ)40°C to + 125°C
EN 0V to 5V
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is intended to be functional, but does not ensure specific performance limits. For ensured specifications and conditions,
see the Electrical Characteristics.
Electrical Characteristics
Limits in standard type are for TJ= 25°C only; limits in boldface type apply over the junction temperature (TJ) range of -40°C
to +125°C. Minimum and Maximum limits are specified through test, design, or statistical correlation. Typical values represent
the most likely parametric norm at TJ= 25°C, and are provided for reference purposes only. Unless otherwise stated the
following conditions apply: VIN = 18V.
Symbol Parameter Conditions Min Typ Max Units
Start-Up Regulator, VCC
VCC CVCC = 1 µF, 0 mA to 40 mA 5.65 5.95 6.25 V
IVCC = 2 mA, VIN = 5.5V 40
VIN - VCC VIN - VCC Dropout Voltage mV
IVCC = 30 mA, VIN = 5.5V 330
IVCCL VCC Current Limit(1) VCC = 0V 65 100 mA
VCC Under-Voltage Lockout Threshold
VCCUVLO VCC Increasing 4.75 5.1 5.40 V
(UVLO)
VCCUVLO-HYS VCC UVLO Hysteresis VCC Decreasing 475 mV
tCC-UVLO-D VCC UVLO Filter Delay 3 µs
IIN Input Operating Current No Switching, VFB = 1V 3.5 5mA
IIN-SD Input Operating Current, Device Shutdown VEN = 0V 32 55 µA
GATE Drive
IQ-BST Boost Pin Leakage VBST VSW = 6V 2 nA
RDS-HG-Pull-Up HG Drive Pull–Up On-Resistance IHG Source = 200 mA 5
RDS-HG-Pull-Down HG Drive Pull–Down On-Resistance IHG Sink = 200 mA 3.4
RDS-LG-Pull-Up LG Drive Pull–Up On-Resistance ILG Source = 200 mA 3.4
RDS-LG-Pull-Down LG Drive Pull–Down On-Resistance ILG Sink = 200 mA 2
Soft-Start
ISS SS Pin Source Current VSS = 0V 5.9 7.7 9.5 µA
ISS-DIS SS Pin Discharge Current 200 µA
Current Limit
ILIM-TH Current Limit Sense Pin Source Current 75 85 95 µA
(1) VCC provides self bias for the internal gate drive and control circuits. Device thermal limitations limit external loading.
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LM3150
SNVS561D SEPTEMBER 2008REVISED MARCH 2011
www.ti.com
Electrical Characteristics (continued)
Limits in standard type are for TJ= 25°C only; limits in boldface type apply over the junction temperature (TJ) range of -40°C
to +125°C. Minimum and Maximum limits are specified through test, design, or statistical correlation. Typical values represent
the most likely parametric norm at TJ= 25°C, and are provided for reference purposes only. Unless otherwise stated the
following conditions apply: VIN = 18V.
Symbol Parameter Conditions Min Typ Max Units
ON/OFF Timer
VIN = 10V, RON = 100 k,1.02
VFB = 0.6V
VIN = 18V, RON = 100 k,
tON ON Timer Pulse Width 0.62 µs
VFB = 0.6V
VIN = 42V, RON = 100 k,0.36
VFB = 0.6V
tON-MIN ON Timer Minimum Pulse Width See(2) 200 ns
tOFF OFF Timer Minimum Pulse Width 370 525 ns
Enable Input
VEN EN Pin Input Threshold Trip Point VEN Rising 1.14 1.20 1.26 V
VEN-HYS EN Pin Threshold Hysteresis VEN Falling 120 mV
Regulation and Over-Voltage Comparator
VFB In-Regulation Feedback Voltage VSS > 0.6V 0.588 0.600 0.612 V
VFB-OV Feedback Over-Voltage Threshold 0.690 0.720 0.748 V
IFB Feedback Bias Current 20 nA
Boost Diode
Forward Voltage IBST = 2 mA 0.7
VfV
IBST = 30 mA 1
Thermal Characteristics
Thermal Shutdown Rising 165 °C
TSD Thermal Shutdown Hysteresis Falling 15 °C
4 Layer JEDEC Printed Circuit 40
Board, 9 Vias, No Air Flow
θJA Junction to Ambient °C/W
2 Layer JEDEC Printed Circuit 140
Board. No Air Flow
θJC Junction to Case No Air Flow 4 °C/W
(2) See Theory of Operation section for minimum on-time when using MOSFETs connected to gate drivers.
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Product Folder Links: LM3150
CBST
EN
SS
BST
SW
ON TIMER
Ron START
COMPLETE
UVLO THERMAL
SHUTDOWN
LEVEL
SHIFT L
LM3150
AVDD
DRIVER
REGULATION
COMPARATOR
VDD
LOGIC DrvH
DrvL
CURRENT LIMIT
COMPARATOR
DRIVER
GND
Vbias
VDD
toff
OFF TIMER
PMOS
input
FB
EN
VIN
RON
VIN
CVCC
VCC
PGND
PGND
CIN
RON
VCC
CSS
SGND
HG
VDD
ILIM
LG
ERM CONTROL
Zero
Current
Detect
VCC
1.20V
6V LDO 0.72V
0.6V
VIN
VOUT
COUT
RFB1
RFB2
RLIM
ILIM-TH
START
COMPLETE
0.72V
M2
M1
ISS
VFB-OV and
SHORT
CIRCUIT
PROTECTION
1.20V
GND
0.36V
1 M5
6V
Vref = 0.6V
LM3150
www.ti.com
SNVS561D SEPTEMBER 2008REVISED MARCH 2011
Simplified Block Diagram
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www.ti.com
Typical Performance Characteristics
Boost Diode Forward Voltage ILIM-TH
vs. vs.
Temperature Temperature
Figure 2. Figure 3.
Quiescent Current Soft-Start Current
vs. vs.
Temperature Temperature
Figure 4. Figure 5.
tON tON
vs. vs.
Temperature Temperature
Figure 6. Figure 7.
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LM3150
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SNVS561D SEPTEMBER 2008REVISED MARCH 2011
Typical Performance Characteristics (continued)
tON VCC Current Limit
vs. vs.
Temperature Temperature
Figure 8. Figure 9.
VCC Dropout VCC
vs. vs.
Temperature Temperature
Figure 10. Figure 11.
Copyright © 2008–2011, Texas Instruments Incorporated Submit Documentation Feedback 7
Product Folder Links: LM3150
VOUT = VFB x (RFB1 + RFB2)
RFB1
fS = VOUT
K x RON
D = tON
tON + tOFF = tON x fS |VOUT
VIN
RON = K x fS
VOUT
tON = K x RON
VIN
LM3150
SNVS561D SEPTEMBER 2008REVISED MARCH 2011
www.ti.com
THEORY OF OPERATION
The LM3150 synchronous step-down SIMPLE SWITCHER®Controller utilizes a Constant On-Time (COT)
architecture which is a derivative of the hysteretic control scheme. COT relies on a fixed switch on-time to
regulate the output. The on-time of the high-side switch can be set manually by adjusting the size of an external
resistor (RON). To maintain a relatively constant switching frequency as VIN varies, the LM3150 automatically
adjusts the on-time inversely with the input voltage. Assuming an ideal system and VIN is much greater than 1V,
the following approximations can be made:
The on-time, tON:
where
constant K = 100 pC (1)
The RON resistance value can be calculated as follows:
where
fsis the desired switching frequency (2)
Control is based on a comparator and the on-timer, with the output voltage feedback (FB) compared with an
internal reference of 0.6V. If the FB level is below the reference, the high-side switch is turned on for a fixed time,
tON, which is determined by the input voltage and the resistor RON. Following this on-time, the switch remains off
for a minimum off-time, tOFF, as specified in the Electrical Characteristics table or until the FB pin voltage is below
the reference, then the switch turns on again for another on-time period. The switching will continue in this
fashion to maintain regulation. During continuous conduction mode (CCM), the switching frequency ideally
depends on duty-cycle and on-time only. In a practical application however, there is a small delay in the time that
the HG goes low and the SW node goes low that also affects the switching frequency that is accounted for in the
typical application curves. The duty-cycle and frequency can be approximated as:
(3)
(4)
Typical COT hysteretic controllers need a significant amount of output capacitor ESR to maintain a minimum
amount of ripple at the FB pin in order to switch properly and maintain efficient regulation. The LM3150 however,
utilizes a proprietary Emulated Ripple Mode control scheme (ERM) that allows the use of low ESR output
capacitors. Not only does this reduce the need for high output capacitor ESR, but also significantly reduces the
amount of output voltage ripple seen in a typical hysteretic control scheme. The output ripple voltage can
become so low that it is comparable to voltage-mode and current-mode control schemes.
Programming the Output Voltage
The output voltage is set by two external resistors (RFB1,RFB2). The regulated output voltage is calculated as
follows:
where
RFB2 is the top resistor connected between VOUT and FB
RFB1 is the bottom resistor connected between FB and GND (5)
Regulation Comparator
The feedback voltage at FB is compared to the internal reference voltage of 0.6V. In normal operation (the output
voltage is regulated), an on-time period is initiated when the voltage at FB falls below 0.6V. The high-side switch
stays on for the on-time, causing the FB voltage to rise above 0.6V. After the on-time period, the high-side switch
stays off until the FB voltage falls below 0.6V.
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Ivalley = IOUT - 'IL
2
RLIM = ICL x RDS(ON)max
ILIM-TH
ICL = IOCL - 'IL
2
LM3150
www.ti.com
SNVS561D SEPTEMBER 2008REVISED MARCH 2011
Over-Voltage Comparator
The over-voltage comparator is provided to protect the output from over-voltage conditions due to sudden input
line voltage changes or output loading changes. The over-voltage comparator continuously monitors the voltage
at the FB pin and compares it to a 0.72V internal reference. If the voltage at FB rises above 0.72V, the on-time
pulse is immediately terminated. This condition can occur if the input or the output load changes suddenly. Once
the over-voltage protection is activated, the HG and LG signals remain off until the voltage at FB pin falls below
0.72V.
Current Limit
Current limit detection occurs during the off-time by monitoring the current through the low-side switch using an
external resistor, RLIM. If during the off-time the current in the low-side switch exceeds the user defined current
limit value, the next on-time cycle is immediately terminated. Current sensing is achieved by comparing the
voltage across the low side FET with the voltage across the current limit set resistor RLIM. If the voltage across
RLIM and the voltage across the low-side FET are equal then the current limit comparator will terminate the next
on-time cycle.
The RLIM value can be approximated as follows:
(6)
where
IOCL is the user-defined average output current limit value
RDS(ON)max is the resistance value of the low-side FETat the expected maximum FET junction temperature
ILIM-TH is an internal current supply of 85 µA typical (7)
Figure 12 illustrates the inductor current waveform. During normal operation, the output current ripple is dictated
by the switching of the FETs. The current through the low-side switch, Ivalley, is sampled at the end of each
switching cycle and compared to the current limit, ICL, current. The valley current can be calculated as follows:
where
IOUT is the average output current
ΔILis the peak-to-peak inductor ripple current (8)
If an overload condition occurs, the current through the low-side switch will increase which will cause the current
limit comparator to trigger the logic to skip the next on-time cycle. The IC will then try to recover by checking the
valley current during each off-time. If the valley current is greater than or equal to ICL, then the IC will keep the
low-side FET on and allow the inductor current to further decay.
Throughout the whole process, regardless of the load current, the on-time of the controller will stay constant and
thereby the positive ripple current slope will remain constant. During each on-time the current ramps-up an
amount equal to:
(9)
The valley current limit feature prevents current runaway conditions due to propagation delays or inductor
saturation since the inductor current is forced to decay following any overload conditions.
Current sensing is achieved by either a low value sense resistor in series with the low-side FET or by utilizing the
RDS(ON) of the low-side FET. The RDS(ON) sensing method is the preferred choice for a more simplified design and
lower costs. The RDS(ON) value of a FET has a positive temperature coefficient and will increase in value as the
FET’s temperature increases. The LM3150 controller will maintain a more stable current limit that is closer to the
original value that was set by the user, by positively adjusting the ILIM-TH value as the IC temperature increases.
This does not provide an exact temperature compensation but allows for a more tightly controlled current limit
when compared to traditional RDS(ON) sensing methods when the RDS(ON) value can change typically 140% from
room to maximum temperature and cause other components to be over-designed. The temperature
compensated ILIM-TH is shown below where TJis the die temperature of the LM3150 in Celsius:
Copyright © 2008–2011, Texas Instruments Incorporated Submit Documentation Feedback 9
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ICL
IPK
'I
IOCL
IOUT
Inductor Current
Load Current
Increases
Normal Operation Current Limited
tSS = Vref x CSS
ISS
LM3150
SNVS561D SEPTEMBER 2008REVISED MARCH 2011
www.ti.com
ILIM-TH(TJ) = ILIM-TH x [1 + 3.3 x 10-3 x (TJ- 27)] (10)
To calculate the RLIM value with temperature compensation, substitute equation (10) into ILIM-TH in equation (7).
Short-Circuit Protection
The LM3150 will sense a short-circuit on the output by monitoring the output voltage. When the feedback voltage
has fallen below 60% of the reference voltage, Vref x 0.6 (0.36V), short-circuit mode of operation will start.
During short-circuit operation, the SS pin is discharged and the output voltage will fall to 0V. The SS pin voltage,
VSS, is then ramped back up at the rate determined by the SS capacitor and ISS until VSS reaches 0.7V. During
this re-ramp phase, if the short-circuit fault is still present the output current will be equal to the set current limit.
Once the soft-start voltage reaches 0.7V the output voltage is sensed again and if the VFB is still below Vref x 0.6
then the SS pin is discharged again and the cycle repeats until the short-circuit fault is removed.
Soft-Start
The soft-start (SS) feature allows the regulator to gradually reach a steady-state operating point, which reduces
start-up stresses and current surges. At turn-on, while VCC is below the under-voltage threshold, the SS pin is
internally grounded and VOUT is held at 0V. The SS capacitor is used to slowly ramp VFB from 0V to 0.6V. By
changing the capacitor value, the duration of start-up can be changed accordingly. The start-up time can be
calculated using the following equation:
where
tSS is measured in seconds
Vref = 0.6V
ISS is the soft-start pin source current, which is typically 7.7 µA (refer to Electrical Characteristics table) (11)
An internal switch grounds the SS pin if VCC is below the under-voltage lockout threshold, if a thermal shutdown
occurs, or if the EN pin is grounded. By using an externally controlled switch, the output voltage can be shut off
by grounding the SS pin.
During startup the LM3150 will operate in diode emulation mode, where the low-side gate LG will turn off and
remain off when the inductor current falls to zero. Diode emulation mode will allow start-up into a pre-biased
output voltage. When soft-start is greater than 0.7V, the LM3150 will remain in continuous conduction mode.
During diode emulation mode at current limit the low-gate will remain off when the inductor current is off.
Figure 12. Inductor Current - Current Limit Operation
The soft-start time should be greater than the input voltage rise time and also satisfy the following equality to
maintain a smooth transition of the output voltage to the programmed regulation voltage during startup.
tSS (VOUT x COUT) / (IOCL - IOUT) (12)
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VOUT = VFB x (RFB1 + RFB2)
RFB1
LM3150
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SNVS561D SEPTEMBER 2008REVISED MARCH 2011
Enable/Shutdown
The EN pin can be activated by either leaving the pin floating due to an internal pull up resistor to VIN or by
applying a logic high signal to the EN pin of 1.26V or greater. The LM3150 can be remotely shut down by taking
the EN pin below 1.02V. Low quiescent shutdown is achieved when VEN is less than 0.4V. During low quiescent
shutdown the internal bias circuitry is turned off.
The LM3150 has certain fault conditions that can trigger shutdown, such as over-voltage protection, current limit,
under-voltage lockout, or thermal shutdown. During shutdown, the soft-start capacitor is discharged. Once the
fault condition is removed, the soft-start capacitor begins charging, allowing the part to start-up in a controlled
fashion. In conditions where there may be an open drain connection to the EN pin, it may be necessary to add a
1 nF bypass capacitor to this pin. This will help decouple noise from the EN pin and prevent false disabling.
Thermal Protection
The LM3150 should be operated such that the junction temperature does not exceed the maximum operating
junction temperature. An internal thermal shutdown circuit, which activates at 165°C (typical), takes the controller
to a low-power reset state by disabling the buck switch and the on-timer, and grounding the SS pin. This feature
helps prevent catastrophic failures from accidental device overheating. When the junction temperature falls back
below 150°C the SS pin is released and device operation resumes.
Design Guide
The design guide provides the equations required to design with the LM3150 SIMPLE SWITCHER®Controller.
WEBENCH®design tool can be used with or in place of this section for a more complete and simplified design
process.
1. Define Power Supply Operating Conditions
a. Required Output Voltage
b. Maximum and Minimum DC Input Voltage
c. Maximum Expected Load Current during Normal Operation
d. Soft-Start Time
2. Set Output Voltage With Feedback Resistors
where
RFB1 is the bottom resistor
RFB2 is the top resistor (13)
3. Determine RON and fs
The available frequency range for a given input voltage range, is determined by the duty-cycle, D = VOUT/VIN, and
the minimum tON and tOFF times as specified in the Electrical Characteristics table. The maximum frequency is
thus, fsmax = Dmin/tON-MIN. Where Dmin=VOUT/VIN-MAX, is the minimum duty-cycle. The off-time will need to be less
than the minimum off-time tOFF as specified in the Electrical Characteristics table plus any turn off and turn on
delays of the MOSFETs which can easily add another 200 ns. The minimum off-time will occur at maximum duty
cycle Dmax and will determine if the frequency chosen will allow for the minimum desired input voltage. The
requirement for minimum off-time is tOFF= (1–Dmax)/fs(tOFF-MIN + 200 ns). If tOFF does not meet this requirement
it will be necessary to choose a smaller switching frequency fS.
Choose RON so that the switching frequency at your typical input voltage matches your fSchosen above using
the following formula:
RON = [(VOUT x VIN)-VOUT] / (VIN x K x fS) + ROND (14)
ROND = - [(VIN - 1) x (VIN x 16.5 + 100)] - 1000 (15)
Use Figure 13 to determine if the calculated RON will allow for the minimum desired input voltage. If the minimum
desired input voltage is not met, recalculate RON for a lower switching frequency.
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ET = (Vinmax ± VOUT) x Vinmax
VOUT xfS
1000 (V x Ps)
LM3150
SNVS561D SEPTEMBER 2008REVISED MARCH 2011
www.ti.com
Figure 13. Minimum VIN vs. VOUT
IOUT = 10 A
4. Determine Inductor Required Using Figure 14
To use the nomograph in Figure 14, calculate the inductor volt-microsecond constant ET from the following
formula:
where
fsis in kHz units (16)
The intersection of the Load Current and the Volt-microseconds lines on the chart below will determine which
inductors are capable for use in the design. The chart shows a sample of parts that can be used. The offline
calculator tools and WEBENCH®will fully calculate the requirements for the components needed for the design.
12 Submit Documentation Feedback Copyright © 2008–2011, Texas Instruments Incorporated
Product Folder Links: LM3150
L36
L35
MAXIMUM LOAD CURRENT (A)
4 5 6 7 8 9 10 12
1
2
3
4
5
6
7
8
9
10
20
30
40
50
60
70
80
90
100 L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
L14
L15
L16
L17
L18
L19
L20
L21
L22
L23
L24
L34
L33
L32
L25
L26
L27
L28
L29
L30
L31
L48
L47
L46
L45
L44
L37
L38
L39
L40
L41
L42
L43
E À T (V À Ps)
47 PH
33 PH
22 PH
15 PH
10 PH
6.8 PH
4.7 PH
3.3 PH
2.2 PH
1.5 PH
1.0 PH
0.68 PH
0.47 PH
0.33 PH
LM3150
www.ti.com
SNVS561D SEPTEMBER 2008REVISED MARCH 2011
Figure 14. Inductor Nomograph
Table 1. Inductor Selection Table
Inductor Designator Inductance Current Part Name Vendor
H) (A)
L01 47 7-9
L02 33 7-9 SER2817H-333KL COILCRAFT
L03 22 7-9 SER2814H-223KL COILCRAFT
L04 15 7-9 7447709150 WURTH
L05 10 7-9 RLF12560T-100M7R5 TDK
L06 6.8 7-9 B82477-G4682-M EPCOS
L07 4.7 7-9 B82477-G4472-M EPCOS
L08 3.3 7-9 DR1050-3R3-R COOPER
L09 2.2 7-9 MSS1048-222 COILCRAFT
L10 1.5 7-9 SRU1048-1R5Y BOURNS
L11 1 7-9 DO3316P-102 COILCRAFT
L12 0.68 7-9 DO3316H-681 COILCRAFT
L13 33 9-12
L14 22 9-12 SER2918H-223 COILCRAFT
L15 15 9-12 SER2814H-153KL COILCRAFT
L16 10 9-12 7447709100 WURTH
L17 6.8 9-12 SPT50H-652 COILCRAFT
L18 4.7 9-12 SER1360-472 COILCRAFT
L19 3.3 9-12 MSS1260-332 COILCRAFT
L20 2.2 9-12 DR1050-2R2-R COOPER
L21 1.5 9-12 DR1050-1R5-R COOPER
L22 1 9-12 DO3316H-102 COILCRAFT
L23 0.68 9-12
L24 0.47 9-12
L25 22 12-15 SER2817H-223KL COILCRAFT
Copyright © 2008–2011, Texas Instruments Incorporated Submit Documentation Feedback 13
Product Folder Links: LM3150
LM3150
SNVS561D SEPTEMBER 2008REVISED MARCH 2011
www.ti.com
Table 1. Inductor Selection Table (continued)
Inductor Designator Inductance Current Part Name Vendor
H) (A)
L26 15 12-15
L27 10 12-15 SER2814L-103KL COILCRAFT
L28 6.8 12-15 7447709006 WURTH
L29 4.7 12-15 7447709004 WURTH
L30 3.3 12-15
L31 2.2 12-15
L32 1.5 12-15 MLC1245-152 COILCRAFT
L33 1 12-15
L34 0.68 12-15 DO3316H-681 COILCRAFT
L35 0.47 12-15
L36 0.33 12-15 DR73-R33-R COOPER
L37 22 15-
L38 15 15- SER2817H-153KL COILCRAFT
L39 10 15- SER2814H-103KL COILCRAFT
L40 6.8 15-
L41 4.7 15- SER2013-472ML COILCRAFT
L42 3.3 15- SER2013-362L COILCRAFT
L43 2.2 15-
L44 1.5 15- HA3778–AL COILCRAFT
L45 1 15- B82477-G4102-M EPCOS
L46 0.68 15-
L47 0.47 15-
L48 0.33 15-
5. Determine Output Capacitance
Typical hysteretic COT converters similar to the LM3150 require a certain amount of ripple that is generated
across the ESR of the output capacitor and fed back to the error comparator. Emulated Ripple Mode control built
into the LM3150 will recreate a similar ripple signal and thus the requirement for output capacitor ESR will
decrease compared to a typical Hysteretic COT converter. The emulated ripple is generated by sensing the
voltage signal across the low-side FET and is then compared to the FB voltage at the error comparator input to
determine when to initiate the next on-time period.
COmin = 70 / (fs2x L) (17)
The maximum ESR allowed to prevent over-voltage protection during normal operation is:
ESRmax = (80 mV x L x Af) / ETmin (18)
ETmin is calculated using VIN-MIN
Af= VOUT / 0.6 if there is no feed-forward capacitor used
Af= 1 if there is a feed-forward capacitor used
The minimum ESR must meet both of the following criteria:
ESRmin (15 mV x L x Af) / ETmax (19)
ESRmin [ ETmax / (VIN - VOUT) ] x (Af/ CO) (20)
ETmax is calculated using VIN-MAX.
Any additional parallel capacitors should be chosen so that their effective impedance will not negatively attenuate
the output ripple voltage.
6. Determine The Use of Feed-Forward Capacitor
Certain applications may require a feed-forward capacitor for improved stability and easier selection of available
output capacitance. Use the following equation to calculate the value of Cff.
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Product Folder Links: LM3150
CIN = Iomax x D x (1-D)
fs x 'VIN-MAX
RLIM (Tj) = ICL x RDS(ON)max
ILIM-TH (Tj)
LM3150
www.ti.com
SNVS561D SEPTEMBER 2008REVISED MARCH 2011
ZFB = (RFB1 x RFB2)/(RFB1 + RFB2) (21)
Cff = VOUT/(VIN-MIN x fSx ZFB) (22)
7. MOSFET and RLIM Selection
The high-side and low-side FETs must have a drain to source (VDS) rating of at least 1.2 x VIN.
Use the following equations to calculate the desired target value of the low-side FET RDS(ON) for current limit.
(23)
ILIM-TH(Tj) = ILIM-TH x [1 + 3.3 x 10-3 x (Tj- 27)] (24)
The gate drive current from VCC must not exceed the minimum current limit of VCC. The drive current from VCC
can be calculated with:
IVCCdrive = Qgtotal x fS
where
Qgtotal is the combined total gate charge of the high-side and low-side FETs (25)
The plateau voltage of the FET VGS vs Qgcurve, as shown in Figure 15, must be less than VCC - 750 mV.
Figure 15. Typical MOSFET Gate Charge Curve
See following design example for estimated power dissipation calculation.
8. Calculate Input Capacitance
The main parameters for the input capacitor are the voltage rating, which must be greater than or equal to the
maximum DC input voltage of the power supply, and its rms current rating. The maximum rms current is
approximately 50% of the maximum load current.
where
ΔVIN-MAX is the maximum allowable input ripple voltage (26)
A good starting point for the input ripple voltage is 5% of VIN.
When using low ESR ceramic capacitors on the input of the LM3150 a resonant circuit can be formed with the
impedance of the input power supply and parasitic impedance of long leads/PCB traces to the LM3150 input
capacitors. It is recommended to use a damping capacitor under these circumstances, such as aluminum
electrolytic that will prevent ringing on the input. The damping capacitor should be chosen to be approximately 5
times greater than the parallel ceramic capacitors combination. The total input capacitance should be greater
than 10 times the input inductance of the power supply leads/pcb trace. The damping capacitor should also be
chosen to handle its share of the rms input current which is shared proportionately with the parallel impedance of
the ceramic capacitors and aluminum electrolytic at the LM3150 switching frequency.
The CBYP capacitor should be placed directly at the VIN pin. The recommended value is 0.1 µF.
Copyright © 2008–2011, Texas Instruments Incorporated Submit Documentation Feedback 15
Product Folder Links: LM3150
RFB2 = 4.99 k:3.3V
0.6V-1
RFB2 = RFB1 VOUT
VFB -1
EN
SS
HG
SW L
LM3150
FB
VCC
PGND
SGND
BST
ILIM
LG
CBYP
CSS
VIN VIN
RON
RON
COUT
VOUT
CBST
CVCC
VIN
RLIM
RFB2
RFB1
M2
M1
CEN
CFF
CIN
CSS = ISS x tSS
Vref
LM3150
SNVS561D SEPTEMBER 2008REVISED MARCH 2011
www.ti.com
9. Calculate Soft-Start Capacitor
where
tss is the soft-start time in seconds
Vref = 0.6V (27)
10. CVCC, CBST and CEN
CVCC should be placed directly at the VCC pin with a recommended value of 1 µF to 4.7 µF. CBST creates a
voltage used to drive the gate of the high-side FET. It is charged during the SW off-time. The recommended
value for CBST is 0.47 µF. The EN bypass capacitor, CEN, recommended value is 1000 pF when driving the EN
pin from open drain type of signal.
Design Example
Figure 16. Design Example Schematic
1.Define Power Supply Operating Conditions
a. VOUT = 3.3V
b. VIN-MIN = 6V, VIN-TYP = 12V, VIN-MAX = 24V
c. Typical Load Current = 12A, Max Load Current = 15A
d. Soft-Start time tSS = 5 ms
2. Set Output Voltage with Feedback Resistors
RFB2 = 22.455 k
RFB2 = 22.6 k, nearest 1% standard value.
3. Determine RON and fS
Dmin = VOUT/VIN-MAX
Dmin = 3.3V/24V = 0.137
Dmax = 3.3V / 6V = 0.55
fsmax = 0.137/ 200 ns = 687 kHz
Dmax = VOUT/VIN-MIN
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Product Folder Links: LM3150
Irmsco = 12 x 12
0.3
Irmsco = IOUT x 12
r
LM3150
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SNVS561D SEPTEMBER 2008REVISED MARCH 2011
tOFF = (1-0.55)/687 kHz = 654 ns
tOFF should meet the following criteria:
tOFF > tOFF-MIN + 200 ns
tOFF > 725 ns
At the maximum switching frequency of 687 kHz, which is limited by the minimum on-time, the off-time of 654 ns
is less than 725 ns. Therefore the switching frequency should be reduced and meet the following criteria:
fs< (1 - D)/725 ns
fS< (1 - 0.55)/725 ns = 620 kHz
A switching frequency is arbitrarily chosen at 500 kHz which should allow for reasonable size components and
satisfies the requirements above.
fS= 500 kHz
Using fS= 500 kHz RON can be calculated as follows:
RON = [(VOUT x VIN)-VOUT] / (VIN x K x fS) + ROND
ROND = - [(VIN - 1) x (VIN x 16.5 + 100)] - 1000
ROND = - [(12 - 1) x (12 x 16.5 + 100)] -1000
ROND = -4.3 k
RON = [(3.3 x 12) - 3.3] / (12 x 100 pC x 500 kHz) - 4.3 k
RON = 56.2 k
Next, check the desired minimum input voltage for RON using Figure 13. This design will meet the desired
minimum input voltage of 6V.
4. Determine Inductor Required
a. ET = (24-3.3) x (3.3/24) x (1000/500) = 5.7 V µs
b. From the inductor nomograph a 12A load and 5.7 V µs calculation corresponds to a L44 type of inductor.
c. Using the inductor designator L44 in Table 1 the Coilcraft HA3778–AL 1.65 µH inductor is chosen.
5. Determine Output Capacitance
The voltage rating on the output capacitor should be greater than or equal to the output voltage. As a rule of
thumb most capacitor manufacturers suggests not to exceed 90% of the capacitor rated voltage. In the case of
multilayer ceramics the capacitance will tend to decrease dramatically as the applied voltage is increased
towards the capacitor rated voltage. The capacitance can decrease by as much as 50% when the applied
voltage is only 30% of the rated voltage. The chosen capacitor should also be able to handle the rms current
which is equal to:
For this design the chosen ripple current ratio, r = 0.3, represents the ratio of inductor peak-to-peak current to
load current IOUT. A good starting point for ripple ratio is 0.3 but it is acceptable to choose r between 0.25 to 0.5.
The nomographs in this datasheet all use 0.3 as the ripple current ratio.
Irmsco = 1A
tON = (3.3V/12V)/500 kHz = 550 ns
Minimum output capacitance is:
COmin = 70 / (fs2x L)
COmin = 70 / (500 kHz2x 1.65 µH) = 169 µF
The maximum ESR allowed to prevent over-voltage protection during normal operation is:
ESRmax = (80 mV x L x Af) / ET
Af= VOUT / 0.6 without a feed-forward capacitor
Af= 1 with a feed-forward capacitor
Copyright © 2008–2011, Texas Instruments Incorporated Submit Documentation Feedback 17
Product Folder Links: LM3150
Pdh = 0.396 + 0.278 = 0.674W
Pcond = Iout2 x RDS(ON) x D
8.5
Vcc - Vth +6.8
Vth
1
2x Vin x Iout x Qgd x fs x
Psw =
Pdh = Pcond + Psw
Pcond = 122 x 0.01 x 0.275 = 0.396W
8.5
6 ± 2.5 +6.8
2.5
1
2x 12 x 12 x 1.5 nC x 500 kHz x
Psw = = 0.278W
Cff = VIN-MIN x fs
VOUT xRFB1 + RFB2
RFB1 x RFB2
Cff = 6V x 500 kHz
3.3V x4.99 k: + 22.6 k:
4.99 k: x 22.6 k:= 269 pF
LM3150
SNVS561D SEPTEMBER 2008REVISED MARCH 2011
www.ti.com
For this design a feed-forward capacitor will be used to help minimize output ripple.
ESRmax = (80 mV x 1.65 µH x 1) / 5.7 V µs
ESRmax = 23 m
The minimum ESR must meet both of the following criteria:
ESRmin (15 mV x L x Af) / ET
ESRmin [ ET / (VIN - VOUT) ] x (Af/ CO)
ESRmin (15 mV x 1.65 µH x 1) / 5.7 V µs = 4.3 m
ESRmin [5.7 V µs / (12 - 3.3) ] x (1 / 169 µF) = 3.9 m
Based on the above criteria two 150 µF polymer aluminum capacitors with a ESR = 12 meach for a effective
ESR in parallel of 6 mwas chosen from Panasonic. The part number is EEF-UE0J101P.
6. Determine Use of Feed-Forward Capacitor
From step 5 the capacitor chosen in ESR is small enough that we should use a feed-forward capacitor. This is
calculated from:
Let Cff = 270 pF, which is the closest next standard value.
7. MOSFET and RLIM Selection
The LM3150 is designed to drive N-channel MOSFETs. For a maximum input voltage of 24V we should choose
N-channel MOSFETs with a maximum drain-source voltage, VDS, greater than 1.2 x 24V = 28.8V. FETs with
maximum VDS of 30V will be the first option. The combined total gate charge Qgtotal of the high-side and low-side
FET should satisfy the following:
Qgtotal IVCCL / fs
Qgtotal 65 mA / 500 kHz
Qgtotal 130 nC
Where IVCCL is the minimum current limit of VCC, over the temperature range, specified in the Electrical
Characteristics table. The MOSFET gate charge Qgis gathered from reading the VGS vs Qgcurve of the
MOSFET datasheet at the VGS = 5V for the high-side, M1, MOSFET and VGS = 6V for the low-side, M2,
MOSFET.
The Renesas MOSFET RJK0305DPB has a gate charge of 10 nC at VGS = 5V, and 12 nC at VGS = 6V. This
combined gate charge for a high-side, M1, and low-side, M2, MOSFET 12 nC + 10 nC = 22 nC is less than 130
nC calculated Qgtotal.
The calculated MOSFET power dissipation must be less than the max allowed power dissipation, Pdmax, as
specified in the MOSFET datasheet. An approximate calculation of the FET power dissipated Pd, of the high-side
and low-side FET is given by:
High-Side MOSFET
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SNVS561D SEPTEMBER 2008REVISED MARCH 2011
The max power dissipation of the RJK0305DPB is rated as 45W for a junction temperature that is 125°C higher
than the case temperature and a thermal resistance from the FET junction to case, θJC, of 2.78°C/W. When the
FET is mounted onto the PCB, the PCB will have some additional thermal resistance such that the total system
thermal resistance of the FET package and the PCB, θJA, is typically in the range of 30°C/W for this type of FET
package. The max power dissipation, Pdmax, with the FET mounted onto a PCB with a 125°C junction
temperature rise above ambient temperature and θJA = 30°C/W, can be estimated by:
Pdmax = 125°C / 30°C/W = 4.1W
The system calculated Pdh of 0.674W is much less than the FET Pdmax of 4.1W and therefore the
RJK0305DPB max allowable power dissipation criteria is met.
Low-Side MOSFET
Primary loss is conduction loss given by:
Pdl = Iout2x RDS(ON) x (1-D) = 122x 0.01 x (1-0.275) = 1W
Pdl is also less than the Pdmax specified on the RJK0305DPB MOSFET datasheet.
However, it is not always necessary to use the same MOSFET for both the high-side and low-side. For most
applications it is necessary to choose the high-side MOSFET with the lowest gate charge and the low-side
MOSFET is chosen for the lowest allowed RDS(ON). The plateau voltage of the FET VGS vs Qgcurve must be less
than VCC - 750 mV.
The current limit resistor, RLIM, is calculated by estimating the RDS(ON) of the low-side FET at the maximum
junction temperature of 100°C. By choosing to go into current limit when the average output load current is 20%
higher than the output load current of 12A while the inductor ripple current ratio is 1/3 of the load current will
make ICL= 10.4A. Then the following calculation of RLIM is:
RLIM = (10.4 x 0.014) / (75 x 10-6) = 1.9 kΩ
Let RLIM = 1.91 kΩwhich is the next standard value.
8. Calculate Input Capacitance
The input capacitor should be chosen so that the voltage rating is greater than the maximum input voltage which
for this example is 24V. Similar to the output capacitor, the voltage rating needed will depend on the type of
capacitor chosen. The input capacitor should also be able to handle the input rms current, which is a maximum
of approximately 0.5 x IOUT. For this example the rms input current is approximately 0.5 x 12A = 6A.
The minimum capacitance with a maximum 5% input ripple ΔVIN-MAX = (0.05 x 12) = 0.6V:
CIN = [12 x 0.275 x (1-0.275)] / [500 kHz x 0.6] = 8 µF
To handle the large input rms current 2 ceramic capacitors are chosen at 10 µF each with a voltage rating of 50V
and case size of 1210. Each ceramic capacitor is capable of handling 3A of rms current. A aluminum electrolytic
of 5 times the combined input capacitance, 5 x 20 µF = 100 µF, is chosen to provide input voltage filter damping
because of the low ESR ceramic input capacitors.
CBYP = 0.1µF ceramic with a voltage rating greater than maximum VIN
9. Calculate Soft-Start Capacitor
The soft start-time should be greater than the input voltage rise time and also satisfy the following equality to
maintain a smooth transition of the output voltage to the programmed regulation voltage during startup. The
desired soft-start time, tss, of 5 ms also needs to satisfy the equality in equation 12, by using the chosen
component values through the previous steps as shown below:
5 ms > (3.3V x 300 µF) / (1.2 x 12A - 12A)
5 ms > 0.412 ms
Since the desired soft-start time satisfies the equality in equation 12, the soft start capacitor is calculated as:
CSS = (7.7 µA x 5 ms) / 0.6V = 0.064 µF
Let CSS = 0.068 µF, which is the next closest standard value. This should be a ceramic cap with a voltage rating
greater than 10V.
Copyright © 2008–2011, Texas Instruments Incorporated Submit Documentation Feedback 19
Product Folder Links: LM3150
LM3150
SNVS561D SEPTEMBER 2008REVISED MARCH 2011
www.ti.com
10. CVCC, CEN, and CBST
CVCC = 4.7 µF ceramic with a voltage rating greater than 10V
CEN = 1000 pF ceramic with a voltage rating greater than 10V
CBST = 0.47 µF ceramic with a voltage rating greater than 10V
Bill of Materials
Designator Value Parameters Manufacturer Part Number
CBST 0.47 µF Ceramic, X7R, 16V, 10% TDK C2012X7R1C474K
CBYP 0.1 µF Ceramic, X7R, 50V, 10% TDK C2012X7R1H104K
CEN 1000 pF Ceramic, X7R, 50V, 10% TDK C1608X7R1H102K
CFF 270 pF Ceramic, C0G, 50V, 5% Vishay-Bccomponents VJ0805A271JXACW1BC
CIN1, CIN2 10 µF Ceramic, X5R, 35V, 20% Taiyo Yuden GMK325BJ106KN-T
COUT1, COUT2 150 µF Polymer Aluminum, , 6.3V, 20% Panasonic EEF-UE0J151R
CSS 0.068 µF Ceramic, 0805, 25V, 10% Vishay VJ0805Y683KXXA
CVCC 4.7 µF Ceramic, X7R, 16V, 10% Murata GRM21BR71C475KA73L
L1 1.65 µH Shielded Drum Core, 2.53 mCoilcraft HA3778–AL
M1, M2 30V 8 nC, RDS(ON) @4.5V=10 mRenesas RJK0305DPB
RFB1 4.99 k1%, 0.125W Vishay-Dale CRCW08054k99FKEA
RFB2 22.6 k1%, 0.125W Vishay-Dale CRCW080522k6FKEA
RLIM 1.91 k1%, 0.125W Vishay-Dale CRCW08051K91FKEA
RON 56.2 k1%, 0.125W Vishay-Dale CRCW080556K2FKEA
U1 LM3150 Texas Instruments LM3150MH
PCB Layout Considerations
It is good practice to layout the power components first, such as the input and output capacitors, FETs, and
inductor. The first priority is to make the loop between the input capacitors and the source of the low-side FET to
be very small and tie the grounds of the low-side FET and input capacitor directly to each other and then to the
ground plane through vias. As shown in Figure 17 when the input capacitor ground is tied directly to the source
of the low-side FET, parasitic inductance in the power path, along with noise coupled into the ground plane, are
reduced.
The switch node is the next item of importance. The switch node should be made only as large as required to
handle the load current. There are fast voltage transitions occurring in the switch node at a high frequency, and if
the switch node is made too large it may act as an antennae and couple switching noise into other parts of the
circuit. For high power designs, it is recommended to use a multi-layer board. The FETs are going to be the
largest heat generating devices in the design, and as such, care should be taken to remove the heat. On multi-
layer boards using exposed-pad packages for the FETs such as the power-pak SO-8, vias should be used under
the FETs to the same plane on the interior layers to help dissipate the heat and cool the FETs. For the typical
single FET Power-Pak type FETs, the high-side FET DAP is VIN. The VIN plane should be copied to the other
interior layers to the bottom layer for maximum heat dissipation. Likewise, the DAP of the low-side FET is
connected to the SW node and the SW node shape should be duplicated to the other PCB layers for maximum
heat dissipation.
See the Evaluation Board application note AN-1900 (SNVA371) for an example of a typical multi-layer board
layout, and the Demonstration Board Reference Design Application Note for a typical 2 layer board layout. Each
design allows for single sided component mounting.
20 Submit Documentation Feedback Copyright © 2008–2011, Texas Instruments Incorporated
Product Folder Links: LM3150
S
S
S
GD
D
D
D
M2
M1
S
S
S
GD
D
D
D
LM3150
HG
LG
HG
LG
VIN VOUT
COUT
L
CIN
x x
vias to
ground plane
PGND
x x
+
-
VIN
CIN
COUT
L
M1
M2
LM3150
www.ti.com
SNVS561D SEPTEMBER 2008REVISED MARCH 2011
Figure 17. Schematic of Parasitics
Figure 18. PCB Placement of Power Stage
Copyright © 2008–2011, Texas Instruments Incorporated Submit Documentation Feedback 21
Product Folder Links: LM3150
PACKAGE OPTION ADDENDUM
www.ti.com 24-Jan-2013
Addendum-Page 1
PACKAGING INFORMATION
Orderable Device Status
(1)
Package Type Package
Drawing Pins Package Qty Eco Plan
(2)
Lead/Ball Finish MSL Peak Temp
(3)
Op Temp (°C) Top-Side Markings
(4)
Samples
LM3150MH/NOPB ACTIVE HTSSOP PWP 14 94 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LM3150
MH
LM3150MHE/NOPB ACTIVE HTSSOP PWP 14 250 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LM3150
MH
LM3150MHX/NOPB ACTIVE HTSSOP PWP 14 2500 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LM3150
MH
(1) The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3) MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4) Only one of markings shown within the brackets will appear on the physical device.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device Package
Type Package
Drawing Pins SPQ Reel
Diameter
(mm)
Reel
Width
W1 (mm)
A0
(mm) B0
(mm) K0
(mm) P1
(mm) W
(mm) Pin1
Quadrant
LM3150MHE/NOPB HTSSOP PWP 14 250 178.0 12.4 6.95 8.3 1.6 8.0 12.0 Q1
LM3150MHX/NOPB HTSSOP PWP 14 2500 330.0 12.4 6.95 8.3 1.6 8.0 12.0 Q1
PACKAGE MATERIALS INFORMATION
www.ti.com 21-Mar-2013
Pack Materials-Page 1
*All dimensions are nominal
Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm)
LM3150MHE/NOPB HTSSOP PWP 14 250 210.0 185.0 35.0
LM3150MHX/NOPB HTSSOP PWP 14 2500 367.0 367.0 35.0
PACKAGE MATERIALS INFORMATION
www.ti.com 21-Mar-2013
Pack Materials-Page 2
MECHANICAL DATA
PWP0014A
www.ti.com
MXA14A (Rev A)
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