SLVS416C February   2002  – January  2015

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  6. Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 Recommended Operating Conditions
    3. 6.3 Thermal Information
    4. 6.4 Dissipation Ratings
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Undervoltage Lock Out (UVLO)
      2. 7.3.2  Slow-Start/Enable (SS/ENA)
      3. 7.3.3  VBIAS Regulator (VBIAS)
      4. 7.3.4  Voltage Reference
      5. 7.3.5  Oscillator and PWM Ramp
      6. 7.3.6  Error Amplifier
      7. 7.3.7  PWM Control
      8. 7.3.8  Dead-Time Control and MOSFET Drivers
      9. 7.3.9  Overcurrent Protection
      10. 7.3.10 Thermal Shutdown
      11. 7.3.11 Powergood (PWRGD)
    4. 7.4 Device Functional Modes
      1. 7.4.1 Continuous Conduction Mode
      2. 7.4.2 Switching Frequency Selection/Synchronization
  8. Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Component Selection
        2. 8.2.2.2 Input Voltage
        3. 8.2.2.3 Feedback Circuit
        4. 8.2.2.4 Operating Frequency
        5. 8.2.2.5 Output Filter
      3. 8.2.3 Application Curves
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Thermal Considerations
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
        1. 11.1.1.1 Related DC - DC Products
    2. 11.2 Related Links
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

6 Specifications

6.1 Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted)(1)
MIN MAX UNIT
VI Input voltage VIN, SS/ENA, SYNC −0.3 7 V
RT −0.3 6 V
VSENSE −0.3 4 V
BOOT −0.3 17 V
VO Output voltage VBIAS, PWRGD, COMP −0.3 7 V
PH −0.6 10 V
IO Source current PH Internally Limited V
COMP, VBIAS 6 mA
IS Sink current PH 6 A
COMP 6 mA
SS/ENA, PWRGD 10 mA
Voltage differential AGND to PGND ±0.3 V
TJ Operating virtual junction temperature –40 125 °C
Tstg Storage temperature −65 150 °C
(1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

6.2 Recommended Operating Conditions

over operating free-air temperature range (unless otherwise noted)
MIN MAX UNIT
VI Input voltage range 3 6 V
TJ Operating junction temperature –40 125 °C

6.3 Thermal Information(2)

THERMAL METRIC(1) TPS5431x UNIT
PWP (28 PINS)
RθJA Junction-to-ambient thermal resistance 26.0 °C/W
Junction-to-ambient thermal resistance (without solder on PowerPad) 57.5
(1) For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.
(2) Test board conditions:
  1. 3 inches × 3 inches, 2 layers, Thickness 0.062 inch
  2. 1.5 oz copper traces located on the top of the PCB
  3. 1.5 oz copper plane on the bottom of the PCB
  4. Ten thermal vias (see recommended land pattern)

6.4 Dissipation Ratings(1)(2)

PACKAGE TA = 25 °C
POWER RATING
TA = 70 °C
POWER RATING
TA = 85 °C
POWER RATING
UNIT
20-Pin PWP with solder 3.85(3) 2.12 1.54 W
20-pin PWP without solder 1.73 0.96 0.69 W
(1) For more information on the PWP package, refer to TI technical brief, SLMA002
(2) Test board conditions:
  1. 3 inches × 3 inches, 2 layers, Thickness 0.062 inch
  2. 1.5 oz copper traces located on the top of the PCB
  3. 1.5 oz copper plane on the bottom of the PCB
  4. Ten thermal vias (see recommended land pattern)
(3) Maximum power dissipation may be limited by overcurrent protection

6.5 Electrical Characteristics

TJ = –40°C to 125°C, VIN = 3 V to 6 V (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
SUPPLY VOLTAGE, VIN
VIN Input voltage range 3 6 V
I(Q) Quiescent current fs = 350 kHz, FSEL ≤ 0.8 V, RT open 6.2 9.6 mA
fs = 550 kHz, FSEL ≤ 2.5 V, RT open, Phase pin open 8.4 12.8
Shutdown, SS/ENA = 0 V 1 1.4
UNDERVOLTAGE LOCK OUT
UVLO Start threshold voltage 2.95 3.0 V
Stop threshold voltage 2.70 2.80 V
Hysteresis voltage 0.14 0.16 V
Rising and falling edge deglitch (1) 2.5 µs
BIAS VOLTAGE
VBIAS Output voltage I(VBIAS) = 0 2.70 2.80 2.90 V
Output current(2) 100 µA
OUTPUT VOLTAGE
VO Output voltage TPS54311 TJ = 25°C, VIN = 5 V 0.9 V
3 V ≤ VIN ≤ 6 V, 0 ≤ IL ≤ 3 A, −40°C ≤ TJ ≤ 125°C –2.5% 2.5%
TPS54312 TJ = 25°C, VIN = 5 V 1.2 V
3 V ≤ VIN ≤ 6 V, 0 ≤ IL ≤ 3 A, −40°C ≤ TJ ≤ 125°C –2.5% 2.5%
TPS54313 TJ = 25°C, VIN = 5 V 1.5 V
3 V ≤ VIN ≤ 6 V, 0 ≤ IL ≤ 3 A, −40°C ≤ TJ ≤ 125°C –2.5% 2.5%
TPS54314 TJ = 25°C, VIN = 5 V 1.8 V
3 V ≤ VIN ≤ 6 V, 0 ≤ IL ≤ 3 A, −40°C ≤ TJ ≤ 125°C –2.5% 2.5%
TPS54315 TJ = 25°C, VIN = 5 V 2.5 V
3 V ≤ VIN ≤ 6 V, 0 ≤ IL ≤ 3 A, −40° ≤ TJ ≤ 125°C –2.5% 2.5%
TPS54316 TJ = 25°C, VIN = 5 V 3.3 V
4 V ≤ VIN ≤ 6 V, 0 ≤ IL ≤ 3 A, −40° ≤ TJ ≤ 125°C −2.5% 2.5%
REGULATION
Line regulation(1)(3) IL = 3 A, 350 ≤ fs ≤ 550 kHz, TJ = 85°C 0.21 %/V
Load regulation(1)(3) IL = 0 A to 3 A, 350 ≤ fs ≤ 550 kHz, TJ = 85°C 0.21 %/A
OSCILLATOR
Internally set-free running frequency FSEL ≤ 0.8 V, RT open 280 350 420 kHz
FSEL ≥ 2.5 V, RT open 440 550 660
Externally set-free running frequency range RT = 180 kΩ (1% resistor to AGND)(1) 252 280 308 kHz
RT = 100 kΩ (1% resistor to AGND) 460 500 540
RT = 68 kΩ (1% resistor to AGND)(1) 663 700 762
High level threshold voltage at FSEL 2.5 V
Low level threshold voltage at FSEL 0.8 V
Ramp valley(1) 0.75 V
Ramp amplitude (peak-to-peak)(1) 1 V
Minimum controllable on time(1) 200 ns
Maximum duty cycle(1) 90%
ERROR AMPLIFIER
Error amplifier open loop voltage gain(4) 26 dB
Error amplifier unity gain bandwidth(4) 3 5 MHz
PWM COMPARATOR
PWM comparator propagation delay time, PWM comparator input to PH pin (excluding dead time) 10-mV overdrive(4) 70 85 ns
SLOW-START/ENABLE
Enable threshold voltage, SS/ENA 0.82 1.20 1.40 V
Enable hysteresis voltage, SS/ENA(4) 0.03 V
Falling edge deglitch, SS/ENA(4) 2.5 µs
Internal slow-start time(4) TPS54311 2.6 3.3 4.1 ms
TPS54312 3.5 4.5 5.4
TPS54313 4.4 5.6 6.7
TPS54314 2.6 3.3 4.1
TPS54315 3.6 4.7 5.6
TPS54316 4.7 6.1 7.6
Charge current, SS/ENA SS/ENA = 0V 3 5 8 µA
Discharge current, SS/ENA SS/ENA = 0.2 V, VI = 1.5 V 1.5 2.3 4 mA
POWERGOOD
Powergood threshold voltage VSENSE falling 90 %Vref
Powergood hysteresis voltage(4) 3 %Vref
Powergood falling edge deglitch(4) 35 µs
Output saturation voltage, PWRGD I(sink) = 2.5 mA 0.18 0.30 V
Leakage current, PWRGD VI = 5.5 V 1 µA
CURRENT LIMIT
Current limit VI = 3 V, output shorted(4) 42 6.5 A
VI = 6 V, output shorted(4) 4.5 7.5
Current limit leading edge blanking time(4) 100 ns
Current limit total response time(4) 200 ns
THERMAL SHUTDOWN
Thermal shutdown trip point(4) 135 150 165 °C
Thermal shutdown hysteresis(4) 10
OUTPUT POWER MOSFETS
rDS(on) Power MOSFET switches VI = 6 V(5) 59 88
IO = 3 A, VI = 3 V(5) 856 136
(1) Specified by design
(2) Static resistive loads only
(3) Specified by the circuit used in Figure 10.
(4) Specified by design
(5) Matched MOSFETs, low side rDS(on) production tested, high side rDS(on) specified by design.

6.6 Typical Characteristics

graph_02_slvs416.gif
Figure 1. Drain-source On-state Resistance
vs Junction Temperature
graph_04_slvs416.gif
Figure 3. Internally Set Oscillator Frequency
vs Junction Temperature
graph_06_slvs416.gif
Figure 5. Voltage Reference vs Junction Temperature
graph_08_slvs416.gif
Figure 7. Error Amplifier Open Loop Response
graph_10_slvs416.gif
Figure 9. Device Power Losses vs Load Current
graph_03_slvs416.gif
Figure 2. Drain-source On-state Resistance
vs Junction Temperature
graph_05_slvs416.gif
Figure 4. Externally Set Oscillator Frequency
vs Junction Temperature
graph_07_slvs416.gif
Figure 6. Output Voltage Regulation vs Input Voltage
graph_09_slvs416.gif
Figure 8. Internal Slow-start Time vs Junction Temperature