SLVSB42D November   2011  ā€“ January 2016 TPS54428

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 PWM Operation
      2. 7.3.2 PWM Frequency and Adaptive On-Time Control
      3. 7.3.3 Auto-Skip Eco-Mode™ Control
    4. 7.4 Device Functional Modes
      1. 7.4.1 Soft Start and Pre-Biased Soft Start
      2. 7.4.2 Current Protection
      3. 7.4.3 UVLO Protection
      4. 7.4.4 Thermal Shutdown
  8. 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 Output Voltage Resistors Selection
        2. 8.2.2.2 Output Filter Selection
        3. 8.2.2.3 Input Capacitor Selection
        4. 8.2.2.4 Bootstrap Capacitor Selection
        5. 8.2.2.5 VREG5 Capacitor Selection
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Examples
    3. 10.3 Thermal Considerations
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
    2. 11.2 Community Resources
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

6 Specifications

6.1 Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted)(1)
MIN MAX UNIT
Input voltage VIN, EN –0.3 20 V
VBST –0.3 26 V
VBST (10 ns transient) –0.3 28 V
VBST (vs SW) –0.3 6.5 V
VFB, SS –0.3 6.5 V
SW –2 20 V
SW (10 ns transient) –3 22 V
Output voltage VREG5 –0.3 6.5 V
GND –0.3 0.3 V
Voltage from GND to thermal pad, Vdiff –0.2 0.2 V
Operating junction temperature, TJ –40 150 °C
Storage temperature, Tstg –55 150 °C
(1) Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under recommended operating conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

6.2 ESD Ratings

VALUE UNIT
V(ESD) Electrostatic discharge Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001(1) ±2000 V
Charged-device model (CDM), per JEDEC specification JESD22-C101(2) ±500 V
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
(2) JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.

6.3 Recommended Operating Conditions

over operating free-air temperature range (unless otherwise noted)
MIN MAX UNIT
VIN Supply input voltage range 4.5 18 V
VI Input voltage range VBST –0.1 24 V
VBST (10 ns transient) -0.1 27 V
VBST(vs SW) –0.1 5.7 V
SS –0.1 5.7 V
EN –0.1 18 V
VFB –0.1 5.5 V
SW –1.8 18 V
SW (10 ns transient) –3 21 V
GND –0.1 0.1 V
VO Output voltage range VREG5 –0.1 5.7 V
IO Output Current range IVREG5 0 10 mA
TA Operating free-air temperature –40 85 °C
TJ Operating junction temperature –40 150 °C

6.4 Thermal Information

THERMAL METRIC(1) TPS54428 UNIT
DDA (SO POWERPAD) DRC (VSON)
8 PINS 10 PINS
RθJA Junction-to-ambient thermal resistance 42.1 43.2 °C/W
RθJCtop Junction-to-case (top) thermal resistance 50.9 53.8 °C/W
RθJB Junction-to-board thermal resistance 31.8 18.2 °C/W
ψJT Junction-to-top characterization parameter 5 0.6 °C/W
ψJB Junction-to-board characterization parameter 13.5 18.3 °C/W
RθJCbot Junction-to-case (bottom) thermal resistance 7.1 4.7 °C/W
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report, SPRA953.

6.5 Electrical Characteristics

over operating free-air temperature range, VIN = 12 V (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
SUPPLY CURRENT
IVIN Operating - non-switching supply current VIN current, TA = 25°C, EN = 5 V,
VFB = 0.8 V		 950 1400 μA
IVINSDN Shutdown supply current VIN current, TA = 25°C, EN = 0 V 3.0 10 μA
LOGIC THRESHOLD
VENH EN high-level input voltage EN 1.6 V
VENL EN low-level input voltage EN 0.6 V
REN EN pin resistance to GND VEN = 12 V 225 450 900 kΩ
VFB VOLTAGE AND DISCHARGE RESISTANCE
VFBTH VFB threshold voltage TA = 25°C, VO = 1.05 V, IO = 10 mA,
Eco-mode™ operation		 771 mV
TA = 25°C, VO = 1.05 V, continuous mode operation 757 765 773
TA = –40°C to 85°C , VO = 1.05V, continuous mode operation(1) 751 765 779
IVFB VFB input current VFB = 0.8 V, TA = 25°C 0 ±0.1 μA
VREG5 OUTPUT
VVREG5 VREG5 output voltage TA = 25°C, 6.0 V < VIN < 18 V,
0 < IVREG5 < 5 mA		 5.2 5.5 5.7 V
VLN5 Line regulation 6 V < VIN < 18 V, IVREG5 = 5 mA 25 mV
VLD5 Load regulation 0 mA < IVREG5 < 5 mA 100 mV
IVREG5 Output current VIN = 6 V, VREG5 = 4.0 V, TA = 25°C 60 mA
MOSFET
RDS(on)h High side switch resistance, DDA 25°C, VBST - SW = 5.5 V 70 mΩ
RDS(on)h High side switch resistance, DRC 25°C, VBST - SW = 5.5 V 74 mΩ
RDS(on)l Low side switch resistance 25°C 53 mΩ
CURRENT LIMIT
Iocl Current limit L out = 1.5 µH (1) 4.6 5.3 6.8 A
THERMAL SHUTDOWN
TSDN Thermal shutdown threshold Shutdown temperature(1) 170 °C
Hysteresis(1) 35
ON-TIME TIMER CONTROL
tON On time VIN = 12 V, VO = 1.05 V 150 ns
tOFF(MIN) Minimum off time TA = 25°C, VFB = 0.7 V 260 310 ns
SOFT START
ISSC SS charge current VSS = 0 V 4.2 6.0 7.8 μA
ISSD SS discharge current VSS = 1 V 0.1 0.2 mA
UVLO
UVLO UVLO threshold Wake up VREG5 voltage 3.45 3.75 4.05 V
Hysteresis VREG5 voltage 0.19 0.32 0.45
(1) Not production tested.

6.6 Typical Characteristics

VIN = 12 V, TA = 25°C (unless otherwise noted)
TPS54428 vin_tj_lvsb42.gif
Figure 1. VIN Current vs Junction Temperature
TPS54428 encur_lvsb42.gif
Figure 3. EN Current vs EN Voltage
TPS54428 out2_105v_lvsb42.gif
Figure 5. 1.05-V Output Voltage vs VIN Voltage
TPS54428 load_eff_lvsb42.gif
Figure 7. Light Load Efficiency vs Output Current
TPS54428 sw_freq_io_lvsb42.gif
Figure 9. Switching Frequency vs Output Current
TPS54428 sd_tj_lvsb42.gif
Figure 2. VIN Shutdown Current vs Junction Temperature
TPS54428 out_105v_lvsb42.gif
Figure 4. 1.05-V Output Voltage vs Output Current
TPS54428 eff_io_lvsb42.gif
Figure 6. Efficiency vs Output Current
TPS54428 sw_freq_lvsb42.gif
Figure 8. Switching Frequency vs Input Voltage
TPS54428 vfb_tj_lvsb42.gif
Figure 10. VFB Voltage vs Junction Temperature