SLUSCE4A January   2017  – July 2017 TPS548B22

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 Timing Requirements
    7. 6.7 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 25-A FET
      2. 7.3.2 On-Resistance
      3. 7.3.3 Package Size, Efficiency and Thermal Performance
      4. 7.3.4 Soft-Start Operation
      5. 7.3.5 VDD Supply Undervoltage Lockout (UVLO) Protection
      6. 7.3.6 EN_UVLO Pin Functionality
      7. 7.3.7 Fault Protections
        1. 7.3.7.1 Current Limit (ILIM) Functionality
        2. 7.3.7.2 Overvoltage Protection (OVP) and Undervoltage Protection (UVP)
        3. 7.3.7.3 Out-of-Bounds Operation
        4. 7.3.7.4 Overtemperature Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 DCAP3 Control Topology
      2. 7.4.2 DCAP Control Topology
    5. 7.5 Programming
      1. 7.5.1 Programmable Pin-Strap Settings
        1. 7.5.1.1 Frequency Selection (FSEL) Pin
        2. 7.5.1.2 VSEL Pin
        3. 7.5.1.3 DCAP3 Control and Mode Selection
        4. 7.5.1.4 Application Workaround to Support 4-ms and 8-ms SS Settings
      2. 7.5.2 Programmable Analog Configurations
        1. 7.5.2.1 RSP/RSN Remote Sensing Functionality
          1. 7.5.2.1.1 Output Differential Remote Sensing Amplifier
        2. 7.5.2.2 Power Good (PGOOD Pin) Functionality
  8. 8 Applications and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 TPS548B22 1.5-V to 18-V Input, 1-V Output, 25-A Converter
      2. 8.2.2 Design Requirements
      3. 8.2.3 Design Procedure
        1. 8.2.3.1  Switching Frequency Selection
        2. 8.2.3.2  Inductor Selection
        3. 8.2.3.3  Output Capacitor Selection
          1. 8.2.3.3.1 Minimum Output Capacitance to Ensure Stability
          2. 8.2.3.3.2 Response to a Load Transient
          3. 8.2.3.3.3 Output Voltage Ripple
        4. 8.2.3.4  Input Capacitor Selection
        5. 8.2.3.5  Bootstrap Capacitor Selection
        6. 8.2.3.6  BP Pin
        7. 8.2.3.7  R-C Snubber and VIN Pin High-Frequency Bypass
        8. 8.2.3.8  Optimize Reference Voltage (VSEL)
        9. 8.2.3.9  MODE Pin Selection
        10. 8.2.3.10 Overcurrent Limit Design.
      4. 8.2.4 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
      1. 10.2.1 Mounting and Thermal Profile Recommendation
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

6 Specifications

6.1 Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted) (1)(2)
MIN MAX UNIT
Input voltage PVIN –0.3 25 V
VDD –0.3 25
BOOT –0.3 34
BOOT to SW DC –0.3 7.7
< 10 ns –0.3 9.0
NU –0.3 6
EN_UVLO, VOSNS, MODE, FSEL, ILIM –0.3 7.7
RSP, RESV_TRK, VSEL –0.3 3.6
RSN –0.3 0.3
PGND, AGND, DRGND –0.3 0.3
SW DC –0.3 25
< 10 ns –5 27
Output voltage PGOOD, BP –0.3 7.7
Junction temperature, TJ –55 150 °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, 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.
(2) All voltage values are with respect to the network ground terminal unless otherwise noted.

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
(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
Input voltage PVIN with no snubber circuit:
SW ringing peak voltage equals 23 V at 25-A output		 1.5 14 V
PVIN with snubber circuit:
SW ringing peak voltage equals 23 V at 25-A output		 1.5 18
VDD 4.5 22
BOOT –0.1 24.5
BOOT to SW DC –0.1 6.5
< 10 ns –0.1 7
NU –0.1 5.5
EN_UVLO, VOSNS, MODE, FSEL, ILIM –0.1 5.5
RSP, RESV_TRK, VSEL –0.1 3.3
RSN –0.1 0.1
PGND, AGND, DRGND –0.1 0.1
SW DC –0.1 18
< 10 ns –5 27
Output voltage PGOOD, BP –0.1 7 V
Junction temperature, TJ –40 125 °C

6.4 Thermal Information

THERMAL METRIC(1) TPS548B22 UNIT
RVF (QFN)
40 PINS
RθJA Junction-to-ambient thermal resistance 28.5 °C/W
RθJC(top) Junction-to-case (top) thermal resistance 18.3 °C/W
RθJB Junction-to-board thermal resistance 3.6 °C/W
ψJT Junction-to-top characterization parameter 0.96 °C/W
ψJB Junction-to-board characterization parameter 3.6 °C/W
RθJC(bot) Junction-to-case (bottom) thermal resistance 0.6 °C/W
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report.

6.5 Electrical Characteristics

over operating free-air temperature range, VVDD = 12 V, VEN_UVLO = 5 V (unless otherwise noted)
PARAMETER TEST CONDITION MIN TYP MAX UNIT
MOSFET ON-RESISTANCE (RDS(on))
RDS(on) High-side FET (VBOOT – VSW) = 5 V, ID = 25 A, TJ = 25°C 4.1 mΩ
Low-side FET VVDD = 5 V, ID = 25 A, TJ = 25°C 1.9 mΩ
INPUT SUPPLY AND CURRENT
VVDD VDD supply voltage Nominal VDD voltage range 4.5 22 V
IVDD VDD bias current No PVIN, EN_UVLO = High, TA = 25°C, 2 mA
IVDDSTBY VDD standby current No PVIN, EN_UVLO = Low, TA = 25°C 700 µA
UNDERVOLTAGE LOCKOUT
VVDD_UVLO VDD UVLO rising threshold 4.23 4.25 4.34 V
VVDD_UVLO(HYS) VDD UVLO hysteresis 0.2 V
VEN_ON_TH EN_UVLO on threshold 1.45 1.6 1.75 V
VEN_HYS EN_UVLO hysteresis 270 300 340 mV
IEN_LKG EN_UVLO input leakage current VEN_UVLO = 5 V –1 0 1 µA
INTERNAL REFERENCE VOLTAGE, EXTERNAL REFIN, AND TRACKING RANGE
VINTREF Internal REF voltage 900.4 mV
VINTREFTOL Internal REF voltage tolerance –40°C ≤ TJ ≤ 125°C –0.5% 0.5%
VINTREF Internal REF voltage range 0.6 1.2 V
OUTPUT VOLTAGE
VIOS_LPCMP Loop comparator input offset voltage(1) –2.5 2.5 mV
IRSP RSP input current VRSP = 600 mV –1 1 µA
IVO(dis) VO discharge current VVO = 0.5 V, power conversion disabled 8 12 mA
DIFFERENTIAL REMOTE SENSE AMPLIFIER
fUGBW Unity gain bandwidth(1) 5 7 MHz
A0 Open loop gain(1) 75 dB
SR Slew rate(1) ±4.7 V/µsec
VIRNG Input range(1) –0.2 1.8 V
VOFFSET Input offset voltage(1) –3.5 3.5 mV
INTERNAL BOOT STRAP SWITCH
VF Forward voltage VBP-BOOT, IF = 10 mA, TA = 25°C 0.1 0.2 V
IBOOT VBST leakage current VBOOT = 30 V, VSW = 25 V, TA = 25°C 0.01 1.5 µA
MODE, VSEL, FSEL DETECTION
VDETECT_TH MODE, VSEL, and FSEL detection voltage VBP = 2.93 V,
RHIGH = 100 kΩ		 Open VBP V
RLOW = 187 kΩ 1.9091
RLOW = 165 kΩ 1.8243
RLOW = 147 kΩ 1.7438
RLOW = 133 kΩ 1.6725
RLOW = 121 kΩ 1.6042
RLOW = 110 kΩ 1.5348
RLOW = 100 kΩ 1.465
RLOW = 90.9 kΩ 1.3952
RLOW = 82.5 kΩ 1.3245
RLOW = 75 kΩ 1.2557
RLOW = 68.1 kΩ 1.187
RLOW = 60.4 kΩ 1.1033
RLOW = 53.6 kΩ 1.0224
RLOW = 47.5 kΩ 0.9436
RLOW = 42.2 kΩ 0.8695
RLOW = 37.4 kΩ 0.7975
RLOW = 33.2 kΩ 0.7303
RLOW = 29.4 kΩ 0.6657
RLOW = 25.5 kΩ 0.5953
RLOW = 22.1 kΩ 0.5303
RLOW = 19.1 kΩ 0.4699
RLOW = 16.5 kΩ 0.415
RLOW = 14.3 kΩ 0.3666
RLOW = 12.1 kΩ 0.3163
RLOW = 10 kΩ 0.2664
RLOW = 7.87 kΩ 0.2138
RLOW = 6.19 kΩ 0.1708
RLOW = 4.64 kΩ 0.1299
RLOW = 3.16 kΩ 0.0898
RLOW = 1.78 kΩ 0.0512
RLOW = 0 Ω GND
PGOOD COMPARATOR
VPGTH PGOOD threshold PGOOD in from higher 105 108 111 %VREF
PGOOD in from lower 89 92 95
PGOOD out to higher 120
PGOOD out to lower 68
IPG PGOOD sink current VPGOOD = 0.5 V 6.9 mA
IPGLK PGOOD leakage current VPGOOD = 5 V –1 0 1 μA
CURRENT DETECTION
VILM VILIM voltage range On-resistance (RDS(on)) sensing 0.1 1.2 V
IOCL_VA Valley current limit threshold RLIM = 61.9 kΩ 30 A
OC tolerance ±15%
RLIM = 51.1 kΩ 25 A
OC tolerance ±15%
RLIM = 40.2 kΩ 17 20 23 A
IOCL_VA_N Negative valley current limit threshold RLIM = 61.9 kΩ –30 A
RLIM = 51.1 kΩ –25
RLIM = 40.2 kΩ –20
ICLMP_LO Clamp current at VLIM clamp at lowest VILIM_CLMP = 0.1 V, TA = 25°C 5 A
ICLMP_HI Clamp current at VLIM clamp at highest VILIM_CLMP = 1.2 V, TA = 25°C 50 A
VZC Zero cross detection offset 0 mV
PROTECTIONS AND OOB
VBPUVLO BP UVLO threshold voltage Wake-up 3.32 V
Shutdown 3.11
VOVP OVP threshold voltage OVP detect voltage 117% 120% 123% VREF
VUVP UVP threshold voltage UVP detect voltage 65% 68% 71% VREF
VOOB OOB threshold voltage 8% VREF
BP VOLTAGE
VBP BP LDO output voltage VIN = 12 V, 0 A ≤ ILOAD ≤ 10 mA, 5.07 V
VBPDO BP LDO drop-out voltage VIN = 4.5 V, ILOAD = 30 mA, TA = 25°C 365 mV
IBPMAX BP LDO over-current limit VIN = 12 V, TA = 25°C 100 mA
THERMAL SHUTDOWN
TSDN Built-In thermal shutdown threshold(1) Shutdown temperature 155 165 °C
Hysteresis 30
(1) Specified by design. Not production tested.

6.6 Timing Requirements

MIN NOM MAX UNIT
SWITCHING FREQUENCY
fSW VO switching frequency(1) VIN = 12 V, VVO = 1 V, TA = 25°C 380 425 475 kHz
585 650 740
790 875 995
950 1050 1250
tON(min) Minimum on time(2) 60 ns
tOFF(min) Minimum off time(2) DRVH falling to rising 300 ns
SOFT-START
tSS Soft-start time VOUT rising from 0 V to 95% of final set point, RMODE_HIGH = 100 kΩ RMODE_LOW = 60.4 kΩ 7 8(3) 10 ms
RMODE_LOW = 53.6 kΩ 3.6 4(4) 5.2 ms
RMODE_LOW = 47.5 kΩ 1.6 2 2.8 ms
RMODE_LOW = 42.2 kΩ 0.8 1 1.6 ms
PGOOD COMPARATOR
tPGDLY PGOOD delay time Delay for PGOOD going in 1 ms
Delay for PGOOD coming out 2 µs
POWER-ON DELAY
tPODLY Power-on delay time 1.024 ms
PROTECTIONS AND OOB
tOVPDLY OVP response time 100-mV over drive 1 µs
tUVPDLY UVP delay filter delay time 1 ms
tHICDLY Hiccup blanking time tSS = 1 ms 16 ms
tSS = 2 ms 24 ms
tSS = 4 ms 38 ms
tSS = 8 ms 67 ms
(1) Correlated with closed-loop EVM measurement at load current of 20 A.
(2) Specified by design. Not production tested.
(3) In order to use the 8-ms SS setting, follow the steps outlined in Application Workaround to Support 4-ms and 8-ms SS Settings.
(4) In order to use the 4-ms SS setting, follow the steps outlined in Application Workaround to Support 4-ms and 8-ms SS Settings.

6.7 Typical Characteristics

TPS548B22 D001_SLUSCE4.gif
VOUT = 1 V VDD = VIN SKIP Mode
fSW = 650 kHz
Figure 1. Efficiency vs Output Current
TPS548B22 D003_SLUSCE4.gif
VOUT = 1 V VDD = VIN SKIP Mode
fSW = 650 kHz
Figure 3. Converter Power Loss vs Output Current
TPS548B22 D005_SLUSCE4.gif
VDD = VIN fSW = 650 kHz SKIP Mode
VOUT = 2.5 V L= 820 nH, 0.9 mΩ
Figure 5. Efficiency vs Output Current
TPS548B22 D002_SLUSCE4.gif
VOUT = 1 V VDD = VIN FCCM Mode
fSW = 650 kHz
Figure 2. Efficiency vs Output Current
TPS548B22 D004_SLUSCE4.gif
VOUT = 1 V VDD = VIN FCCM Mode
fSW = 650 kHz
Figure 4. Output Voltage Regulation vs Output Current
TPS548B22 D006_SLUSCE4.gif
VDD = VIN fSW = 650 kHz SKIP Mode
VOUT = 2.5 V L= 820 nH, 0.9 mΩ
Figure 6. Output Voltage Regulation vs Output Current
TPS548B22 D007_SLUSCE4.gif
VDD = VIN fSW = 650 kHz FCCM Mode
VOUT = 5 V L= 820 nH, 0.9 mΩ
Figure 7. Efficiency vs Output Current
TPS548B22 Therm_Image_1V-Out_12V-In_SLUSCE4.gif
VDD = VIN = 12 V fSW = 650 kHz IOUT = 25 A
VOUT = 1 V Natural convection at room temperature
Figure 9. Thermal Image
TPS548B22 Therm_Image_2p5V-Out_12V-In_SLUSCE4.gif
VDD = VIN = 12 V fSW = 650 kHz IOUT = 25 A
VOUT = 2.5 V Natural convection at room temperature
Figure 11. Thermal Image
TPS548B22 D008_SLUSCE4.gif
VDD = VIN fSW = 650 kHz FCCM Mode
VOUT = 5 V L= 820 nH, 0.9 mΩ
Figure 8. Power Loss vs Output Current
TPS548B22 Therm_Image_1V-Out_18V-In_SLUSCE4.gif
VDD = VIN = 18 V fSW = 650 kHz IOUT = 25 A
VOUT = 1 V Natural convection at room temperature
Figure 10. Thermal Image
TPS548B22 Therm_Image_5V-Out_12V-In_SLUSCE4.gif
VDD = VIN = 12 V fSW = 650 kHz IOUT = 25 A
VOUT = 5 V Natural convection at room temperature
Figure 12. Thermal Image