SLUSF22B November   2024  – March 2025 TPS54338 , TPS54438 , TPS54538

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1  Fixed Frequency Peak Current Mode
      2. 6.3.2  Mode Selection
      3. 6.3.3  Voltage Reference
      4. 6.3.4  Output Voltage Setting
      5. 6.3.5  Switching Frequency Selection / Synchronization
      6. 6.3.6  Phase Shift
      7. 6.3.7  Enable and Adjusting Undervoltage Lockout
      8. 6.3.8  External Soft Start and Prebiased Soft Start
      9. 6.3.9  Power Good
      10. 6.3.10 Minimum On Time, Minimum Off Time, and Frequency Foldback
      11. 6.3.11 Frequency Spread Spectrum
      12. 6.3.12 Overvoltage Protection
      13. 6.3.13 Overcurrent and Undervoltage Protection
      14. 6.3.14 Thermal Shutdown
    4. 6.4 Device Functional Modes
      1. 6.4.1 Modes Overview
      2. 6.4.2 Heavy Load Operation
      3. 6.4.3 Pulse Frequency Modulation
      4. 6.4.4 Forced Continuous Conduction Modulation
      5. 6.4.5 Dropout Operation
      6. 6.4.6 Minimum On-Time Operation
      7. 6.4.7 Shutdown Mode
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
        1. 7.2.2.1 Custom Design With WEBENCH® Tools
        2. 7.2.2.2 Output Voltage Resistors Selection
        3. 7.2.2.3 Choosing Switching Frequency
        4. 7.2.2.4 Soft-Start Capacitor Selection
        5. 7.2.2.5 Output Inductor Selection
        6. 7.2.2.6 Output Capacitor Selection
        7. 7.2.2.7 Input Capacitor Selection
        8. 7.2.2.8 Feedforward Capacitor CFF Selection
        9. 7.2.2.9 Maximum Ambient Temperature
      3. 7.2.3 Application Curves
    3. 7.3 Best Design Practices
    4. 7.4 Power Supply Recommendations
    5. 7.5 Layout
      1. 7.5.1 Layout Guidelines
      2. 7.5.2 Layout Example
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Third-Party Products Disclaimer
      2. 8.1.2 Development Support
        1. 8.1.2.1 Custom Design With WEBENCH® Tools
    2. 8.2 Documentation Support
      1. 8.2.1 Related Documentation
    3. 8.3 Receiving Notification of Documentation Updates
    4. 8.4 Support Resources
    5. 8.5 Trademarks
    6. 8.6 Electrostatic Discharge Caution
    7. 8.7 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

5.5 Electrical Characteristics

The electrical ratings specified in this section apply to all specifications in this document, unless otherwise noted. These specifications are interpreted as conditions that do not degrade the device parametric or functional specifications for the life of the product. Typical values correspond to TJ = 25°C, VIN = 12V. Minimum and maximum limits are based on TJ = –40°C to +150°C, VIN = 3.8V to 28V, unless otherwise noted.
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
POWER SUPPLY (VIN PIN)
VIN Operation input voltage 3.8 28 V
IQ Nonswitching quiescent current EN = 5V, VFB = 0.65V, VIN = 12V, PFM 28 34 µA
EN = 5V, VFB = 0.65V, VIN = 12V, FCCM 40 47
ISHDN Shutdown supply current VEN = 0V, VIN = 12V 3 5.5 µA
VIN_UVLO Input undervoltage lockout thresholds Rising threshold 3.4 3.6 3.8 V
Falling threshold 3.2 3.4 3.6 V
Hysteresis 200 mV
ENABLE (EN PIN)
VEN_RISE Enable threshold Rising enable threshold 1.15 1.22 V
VEN_FALL

Disable threshold

 Falling disable threshold 0.9 1 V
Ip EN pullup current VEN = 1.0V 0.7 µA
Ih EN pullup hysteresis current 1.76 µA
VOLTAGE REFERENCE (FB PIN)
VFB FB voltage TJ = 25°C 596 600 604 mV
TJ = 0°C to 85°C 595 600 605 mV
TJ = –40°C to 150°C 594 600 606 mV
IFB Input leakage current VIN = 12V, VFB = 0.8V, TJ = 25°C 0.1 μA
INTEGRATED POWER MOSFETS
RDSON_HS High-side MOSFET on-resistance TJ = 25°C 47 mΩ
RDSON_LS Low-side MOSFET on-resistance TJ = 25°C 21 mΩ
CURRENT LIMIT
IHS_LIMIT High-side MOSFET current limit VIN = 12V, TPS54538 7 8.1 9.4 A
VIN = 12V, TPS54438 5.6 6.7 7.7
VIN = 12V, TPS54338 4.2 5 6
ILS_LIMIT Low-side MOSFET current limit VIN = 12V, TPS54538 5 6 7 A
VIN = 12V, TPS54438 4 5.1 6.3
VIN = 12V, TPS54338 2.9 3.8 4.7
ILS_NOC Reverse current limit VIN = 12V, TPS54538 2 3 4.2 A
VIN = 12V, TPS54438 1.5 2.6 3.9
VIN = 12V, TPS54338 1.3 2.4 3.5
IPEAK_MIN Minimum peak inductor current VIN = 12V, TPS54538, TPS54438 0.7 A
VIN = 12V, TPS54338 0.56
SOFT START (SS PIN)
ISS Soft-start charge current 3.5 5.5 6.5 μA
TSS Fixed internal soft-start time

Mode with PG function.

Time from 0%Vout-90%Vout

 3.6 ms
POWER GOOD (PG PIN)
VPGTH PG threshold, VFB percentage VFB falling, PG high to low 85%
VFB rising, PG low to high 90%
VFB falling, PG low to high 107%
VFB rising, PG high to low 115%
TPG_R PG delay time PG from low to high 70 μs
TPG_F PG delay time PG from high to low 13 μs
VIN_PG_VALID Minimum VIN for valid PG output Measured when PG < 0.5V with 100kΩ pullup to external 5V 2 2.5 V
VPG_OL PG output low-level voltage IPG = 0.5mA 0.3 V
IPG_LK PG leakage current when open drain is high VPG = 5.5V –1 1 μA
OSCILLATOR FREQUENCY (RT PIN)
fSW Switching center frequency RT = floating 450 500 550 kHz
RT = GND 870 1000 1130
VSYNC_HI SYNC clock high level threshold 1.7 V
VSYNC_LO SYNC clock low level threshold 0.9 V
tON_MIN(1) Minimum ON pulse width 70 ns
tOFF_MIN(1) Minimum OFF pulse width 114 ns
tON_MAX(1) Maximum ON pulse width 8 μs
OUTPUT OVERVOLTAGE AND UNDERVOLTAGE PROTECTION
VOVP Output OVP threshold OVP detect (L→H) 112% 115% 118%
Hysteresis 8%
VUVP Output UVP threshold UVP detect (H→L) 65%
Hysteresis 6%
thiccup_ON UV hiccup ON time before entering hiccup mode after soft start ends 256 μs
thiccup_OFF UV hiccup OFF time before restart 9.8 cycles
THERMAL SHUTDOWN
TSHDN(1) Thermal shutdown threshold Shutdown temperature 165 °C
THYS(1) Hysteresis 30 °C
SPREAD SPECTRUM FREQUENCY
fm(1) Modulation frequency 10 kHz
fspread Internal spread oscillator frequency ±8%
(1) Not production tested, specified by design.