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TPS51125RGER

Dual-Synchronous, Step-Down Controller

The TPS51125RGER is a dual-synchronous, step-down controller from Texas Instruments. View the full TPS51125RGER datasheet below including key specifications, pinout, electrical characteristics, absolute maximum ratings.

TPS51125RGER shares its datasheet with TPS51125, whose page lists every part number it covers.

Official TPS51125RGER datasheet (PDF) — the source this page was extracted from.

Manufacturer

Texas Instruments

Category

Dual-Synchronous, Step-Down Controller

Package

24-VFQFN Exposed Pad

Lifecycle

Active

TPS51125RGER Key Specifications

ParameterValue
Clock SyncNo
Control FeaturesEnable, On Time Control, Power Good
FunctionStep-Down
Mounting TypeSurface Mount
Number of Outputs2
Operating Temperature-40°C ~ 85°C (TA)
Output ConfigurationPositive
Output Phases1
Output TypeTransistor Driver
Package / Case24-VFQFN Exposed Pad
PackagingMouseReel
Standard Pack Qty3000
Supplier Device Package24-VQFN (4x4)
Synchronous RectifierYes
TopologyBuck
Supply Voltage5.5V ~ 28V

TPS51125RGER Overview

Part: TPS51125 — Texas Instruments

Type: Dual-Synchronous, Step-Down Controller

Description: A cost-effective, dual-synchronous buck controller targeted for notebook system power supply solutions, providing 5-V and 3.3-V LDOs, operating with 5.5 V to 28 V input and supporting 2 V to 5.5 V output.

Operating Conditions:

  • Supply voltage: 5.5 V to 28 V
  • Operating temperature: -40 to 85 °C
  • Output voltage range: 2 V to 5.5 V
  • LDO output current: 100 mA

Absolute Maximum Ratings:

  • Max supply voltage: 30 V (VIN)
  • Max junction temperature: 125 °C

Key Specs:

  • VREF output voltage: 1.98 V to 2.02 V (I VREF = 0 A)
  • VREG5 output voltage: 4.8 V to 5.2 V (VO1 = 0 V, I VREG5 < 100 mA, T A = 25°C)
  • VREG3 output voltage: 3.2 V to 3.46 V (VO2 = 0 V, I VREG3 < 100 mA, T A = 25°C)
  • VREG5 output current: 100 mA (VO1 = 0 V, VREG5 = 4.5 V)
  • VREG3 output current: 100 mA (VO2 = 0 V, VREG3 = 3 V)
  • VIN supply current (no load): 0.55 mA (Typ, T A = 25°C, VO1 = 0 V, VO2 = 0 V, EN0=open, ENTRIPx = 5 V, VFB1 = VFB2 = 2.05 V)
  • Clock frequency (VCLK): 175 kHz to 325 kHz (Typ 270 kHz, T A = 25 °C)
  • Minimum on time: 80 ns (Typ, T A = 25 °C)

Features:

  • Wide Input Voltage Range: 5.5 V to 28 V
  • Output Voltage Range: 2 V to 5.5 V
  • Built-In 100-mA, 5-V and 3.3-V LDO With Switches
  • Built-In 1% 2-V Reference Output
  • With or Without Out-of-Audio™ Mode Selectable Light-Load and PWM-Only Operation
  • Adaptive On-Time Control Architecture With Four Selectable Frequency Setting
  • Built-In OVP/UVP/OCP
  • Thermal Shutdown (Nonlatch)

Applications:

  • Notebook Computers
  • I/O Supplies
  • System Power Supplies

Package:

  • VQFN (24)

TPS51125RGER Features

  • 1 · Wide Input Voltage Range: 5.5 V to 28 V
  • Output Voltage Range: 2 V to 5.5 V
  • Built-In 100-mA, 5-V and 3.3-V LDO With Switches
  • Built-In 1% 2-V Reference Output
  • With or Without Out-of-Audio™ Mode Selectable Light-Load and PWM-Only Operation
  • Internal 1.6-ms Voltage Servo Soft-Start
  • Adaptive On-Time Control Architecture With Four Selectable Frequency Setting
  • 4500 ppm/°C RDS(on) Current Sensing
  • Built-In Output Discharge
  • Powergood Output
  • Built-In OVP/UVP/OCP
  • Thermal Shutdown (Nonlatch)
  • QFN, 24-Pin (RGE)

TPS51125RGER Applications

  • Notebook Computers
  • I/O Supplies
  • System Power Supplies

TPS51125RGER Pin Configuration

TPS51125RGER Pinout

Package: 24-VFQFN Exposed Pad

Pin NumberPin NameTypeDescription
1ENTRIP1I/OChannel 1 and Channel 2 enable and OCL trip setting pins. Connect resistor from this pin to GND to set threshold for synchronous RDS(on) sense. Short to ground to shutdown a switcher channel.
2VFB1IFeedback voltage input for channel 1.
3VREFIReference voltage input.
4TONSELIOn-time adjustment pin. 365 kHz/460 kHz setting: connect to VREG5. 300 kHz/375 kHz setting: connect to VREG3. 245 kHz/305 kHz setting: connect to VREF. 200 kHz/250 kHz setting: connect to GND.
5VFB2IFeedback voltage input for channel 2.
6ENTRIP2I/OChannel 1 and Channel 2 enable and OCL trip setting pins. Connect resistor from this pin to GND to set threshold for synchronous RDS(on) sense. Short to ground to shutdown a switcher channel.
7VO2-Output voltage sense for channel 2.
8VREG3-Internal 3V regulator output.
9VBST2-Bootstrap voltage for channel 2 high-side driver.
10DRVH2OHigh-side N-channel MOSFET driver output. LL referenced driver.
11LL2ISwitch node connection for high-side driver, current limit and control circuitry.
12DRVL2OLow-side N-channel MOSFET driver output. GND referenced driver.
13EN0I/OMaster enable input. Open: LDOs on, and ready to turn on VCLK and switcher channels. 620 kΩ to GND: enable both LDOs, VCLK off and ready to turn on switcher channels. GND: disable all circuits.
14SKIPSELISelection pin for operation mode. OOA auto skip: Connect to VREG3. Auto skip: Connect to VREF. Auto skip: Connect to VREF.
15GND-Ground.
16VIN-Input voltage supply.
17VREG5-Internal 5V regulator output.
18VCLK-Clock output.
19DRVL1OLow-side N-channel MOSFET driver output. GND referenced driver.
20LL1ISwitch node connection for high-side driver, current limit and control circuitry.
21DRVH1OHigh-side N-channel MOSFET driver output. LL referenced driver.
22VBST1-Bootstrap voltage for channel 1 high-side driver.
23PGOODOPower Good window comparator output for channel 1 and 2 (Logical AND).
24VO1-Output voltage sense for channel 1.
EPExposed Pad-Exposed pad (thermal/ground connection).

Notes

  • Pin numbers extracted from the package diagram (top view).
  • DRVH1, DRVH2, DRVL1, DRVL2 are driver outputs for dual-channel synchronous buck converter.
  • VBST1, VBST2, VREG3, VREG5 are internal supply nodes; typical connection requirements apply per datasheet.
  • VO1, VO2 are output voltage sense pins for feedback control.
  • EN0 has three operating modes controlled by connection to different voltage levels.
  • SKIPSEL and TONSEL are mode/frequency selection pins with multiple configuration options.

TPS51125RGER Electrical Characteristics

over operating free-air temperature range, VIN = 12 V (unless otherwise noted)

PARAMETERTEST CONDITIONSMINTYPMAXUNIT
SUPPLY CURRENTSUPPLY CURRENTSUPPLY CURRENTSUPPLY CURRENTSUPPLY CURRENTSUPPLY CURRENTSUPPLY CURRENT
I VIN1VIN supply current1VIN current, T A = 25°C, no load, VO1 = 0 V, VO2 = 0 V, EN0=open, ENTRIPx = 5 V, VFB1 = VFB2 = 2.05 V0.551mA
I VIN2VIN supply current2VIN current, T A = 25°C, no load, VO1 = 5 V, VO2 = 3.3 V, EN0=open, ENTRIPx = 5 V, VFB1 = VFB2 = 2.05 V46.5μ A
I VO1VO1 currentVO1 current, T A = 25°C, no load, VO1 = 5 V, VO2 = 3.3 V, EN0=open, ENTRIPx = 5 V, VFB1 = VFB2 = 2.05 V0.81.5mA
I VO2VO2 currentVO2 current, T A = 25°C, no load, VO1 = 5 V, VO2 = 3.3 V, EN0=open, ENTRIPx = 5 V, VFB1 = VFB2 = 2.05 V12100
I VINSTBYVIN standby currentVIN current, T A = 25°C, no load, EN0 = 1.2 V, ENTRIPx = 0 V95250μ A
I VINSDNVIN shutdown currentVIN current, T A = 25°C, no load, EN0 = ENTRIPx = 0 V1025
VREF OUTPUTVREF OUTPUTVREF OUTPUTVREF OUTPUTVREF OUTPUTVREF OUTPUTVREF OUTPUT
VVREF output voltageI VREF = 0 A1.982.002.02V
VREF-5 μ A < I VREF < 100 μ A1.972.002.03
VREG5 OUTPUTVREG5 OUTPUTVREG5 OUTPUTVREG5 OUTPUTVREG5 OUTPUTVREG5 OUTPUTVREG5 OUTPUT
V VREG5VREG5 output voltageVO1 = 0 V, I VREG5 < 100 mA, T A = 25°C4.855.2V
V VREG5VREG5 output voltageVO1 = 0 V, I VREG5 < 100 mA, 6.5 V < VIN < 28 V4.7555.25
VREG5 output currentVO1 = 0 V, I VREG5 < 50 mA, 5.5 V < VIN < 28 V4. 7555.25
I VREG5VO1 = 0 V, VREG5 = 4.5 V100175250mA
Switch over thresholdTurns on4.554.74.85
V TH5VSWHysteresis0.150.250.3V
R 5VSW5 V SW R ONVO1 = 5 V, I VREG5 = 100 mA13Ω
VREG3 OUTPUTVREG3 OUTPUTVREG3 OUTPUTVREG3 OUTPUTVREG3 OUTPUTVREG3 OUTPUTVREG3 OUTPUT
V VREG3VREG3 output voltageVO2 = 0 V, I VREG3 < 100 mA, T A = 25°C3.23.333.46V
V VREG3VREG3 output voltageVO2 = 0 V, I VREG3 < 100 mA, 6.5 V < VIN < 28 V3.133.333.5
V VREG3VREG3 output voltageVO2 = 0 V, I VREG3 < 50 mA, 5.5 V < VIN < 28 V3.133.333.5
I VREG3VREG3 output currentVO2 = 0 V, VREG3 = 3 V100175250mA
Turns on3.053.153.25
V TH3VSWSwitch over thresholdHysteresis0.10.20.25V
R 3VSW3 V SW R ONVO2 = 3.3 V, I VREG3 = 100 mA1.54Ω
INTERNAL REFERENCE VOLTAGEINTERNAL REFERENCE VOLTAGEINTERNAL REFERENCE VOLTAGEINTERNAL REFERENCE VOLTAGEINTERNAL REFERENCE VOLTAGEINTERNAL REFERENCE VOLTAGEINTERNAL REFERENCE VOLTAGE
V IREFInternal reference voltageI VREF = 0 A, beginning of ON state1.951.982.01
FB voltage, I VREF = 0 A, skip mode1.982.012.04
V VFBVFB regulation voltageFB voltage, I VREF = 0 A, OOA mode (1)2.002.0352.07V
V VFBFB voltage, I VREF = 0 A, continuous conduction (1)2.00
I VFBVFB input currentVFBx = 2.0 V, T A = 25°C-2020nA

TPS51125RGER Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted)

MINMAXUNIT
Input voltage (1)VBST1, VBST2-0.336V
Input voltage (1)VIN-0.330V
Input voltage (1)LL1, LL2-230V
Input voltage (1)LL1, LL2, pulse width < 20 ns-530V
Input voltage (1)VBST1, VBST2 (2)-0.36V
Input voltage (1)EN0, ENTRIP1, ENTRIP2, VFB1, VFB2, VO1, VO2, TONSEL, SKIPSEL-0.36V
OutputDRVH1, DRVH2-136V
OutputDRVH1, DRVH2 (2)-0.36V
OutputPGOOD, VCLK, VREG3, VREG5, VREF, DRVL1, DRVL2-0.36V
Junction temperature, T JJunction temperature, T J-40125°C
Storage temperature, T stgStorage temperature, T stg-55150°C

TPS51125RGER Recommended Operating Conditions

over operating free-air temperature range (unless otherwise noted)

MINMAXUNIT
Supply voltageVIN5.528
Input voltageVBST1, VBST2-0.134
VBST1, VBST2 (with respect to LLx)-0.15.5
EN0, ENTRIP1, ENTRIP2, VFB1, VFB2, VO1, VO2, TONSEL, SKIPSEL-0.15.5
Output voltageDRVH1, DRVH2-0.834V
Output voltageDRVH1, DRVH2 (with respect to LLx)-0.15.5V
Output voltageLL1, LL2-1.828V
Output voltageVREF, VREG3, VREG5-0.15.5V
Output voltagePGOOD, VCLK, DRVL1, DRVL2-0.15.5V
Operating free-air temperatureOperating free-air temperature-4085°C

TPS51125RGER Thermal Information

THERMAL METRIC (1)TPS51125 VQFNUNIT
24 PINS
R θ JAJunction-to-ambient thermal resistance34.2°C/W
R θ JC(top)Junction-to-case (top) thermal resistance37.2°C/W
R θ JBJunction-to-board thermal resistance12.4°C/W
ψ JTJunction-to-top characterization parameter0.4°C/W
ψ JBJunction-to-board characterization parameter12.4°C/W
R θ JC(bot)Junction-to-case (bottom) thermal resistance2.8°C/W

TPS51125RGER Typical Application

The TPS51125 is typically used as a dual-synchronous buck controller, which convert an input voltage ranging from 5.5 V to 28 V, to output voltage 5 V and 3.3 V respectively, targeted for notebook system-power supply solutions.

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