TPS51285B

ACTIVE

5-V to 24-V, dual-synchronous buck controller with ultra-low quiescent current

Product details

Vin (min) (V) 5 Vin (max) (V) 24 Iout (max) (A) 20 Operating temperature range (°C) -40 to 85 Control mode D-CAP Topology Buck Rating Catalog Vout (min) (V) 4.5 Vout (max) (V) 5.5 Features Enable, Light Load Efficiency, Power good, Synchronous Rectification Iq (typ) (µA) 84 Duty cycle (max) (%) 100 Number of phases 1
Vin (min) (V) 5 Vin (max) (V) 24 Iout (max) (A) 20 Operating temperature range (°C) -40 to 85 Control mode D-CAP Topology Buck Rating Catalog Vout (min) (V) 4.5 Vout (max) (V) 5.5 Features Enable, Light Load Efficiency, Power good, Synchronous Rectification Iq (typ) (µA) 84 Duty cycle (max) (%) 100 Number of phases 1
WQFN (RUK) 20 9 mm² 3 x 3
  • Input Voltage Range: 5 V to 24 V
  • Output Voltages: 5 V and 3.3 V
    (Adjustable Range ±10%)
  • Built-in, 100-mA, 5-V and 3.3-V
    LDOs
  • Clock Output for Charge-Pump
  • ±1% Reference Accuracy
  • Adaptive On-Time D-CAP Mode Control
    Architecture with 400 kHz (CH1) and
    475 kHz (CH2) Frequency
  • Auto-skip and ULQ modes for long
    battery life in system stand-by mode
  • Internal 0.8-ms Voltage Servo Soft-Start
  • Low-Side RDS(on) Current Sensing Scheme
  • Built-In Output Discharge Function
  • Separate Enable Input for Switchers
  • Dedicated OC Setting Terminals
  • Power Good Indicator
  • OVP, UVP and OCP Protection
  • Non-Latch UVLO and OTP Protection
  • 20-Pin, 3 mm × 3 mm, QFN (RUK)
  • Input Voltage Range: 5 V to 24 V
  • Output Voltages: 5 V and 3.3 V
    (Adjustable Range ±10%)
  • Built-in, 100-mA, 5-V and 3.3-V
    LDOs
  • Clock Output for Charge-Pump
  • ±1% Reference Accuracy
  • Adaptive On-Time D-CAP Mode Control
    Architecture with 400 kHz (CH1) and
    475 kHz (CH2) Frequency
  • Auto-skip and ULQ modes for long
    battery life in system stand-by mode
  • Internal 0.8-ms Voltage Servo Soft-Start
  • Low-Side RDS(on) Current Sensing Scheme
  • Built-In Output Discharge Function
  • Separate Enable Input for Switchers
  • Dedicated OC Setting Terminals
  • Power Good Indicator
  • OVP, UVP and OCP Protection
  • Non-Latch UVLO and OTP Protection
  • 20-Pin, 3 mm × 3 mm, QFN (RUK)

The TPS51285A and TPS51285B are cost-effective, dual synchronous buck controllers with 5-V and 3.3-V LDOs, targeted for notebook system-power supply solutions. The device achieves low power consumption by the use of auto-skip and ULQ™ modes, which is beneficial for long battery life in system stand-by mode. The 256-kHz VCLK output is provided to drive an external charge pump, generating gate drive voltage for the load switches with minimum power consumption in the main converter. The device employs adaptive on-time D-CAP™ mode control which enables fast load transient response without external compensation network. The TPS51285A/B operates with supply input voltage ranging from 5V to 24V and supports output voltages of 5 V and 3.3 V. The TPS51285A and TPS51285B are available in a 20-pin 3 x 3 (mm) QFN package and is specified from –40°C to 85°C.

The TPS51285A and TPS51285B are cost-effective, dual synchronous buck controllers with 5-V and 3.3-V LDOs, targeted for notebook system-power supply solutions. The device achieves low power consumption by the use of auto-skip and ULQ™ modes, which is beneficial for long battery life in system stand-by mode. The 256-kHz VCLK output is provided to drive an external charge pump, generating gate drive voltage for the load switches with minimum power consumption in the main converter. The device employs adaptive on-time D-CAP™ mode control which enables fast load transient response without external compensation network. The TPS51285A/B operates with supply input voltage ranging from 5V to 24V and supports output voltages of 5 V and 3.3 V. The TPS51285A and TPS51285B are available in a 20-pin 3 x 3 (mm) QFN package and is specified from –40°C to 85°C.

Download View video with transcript Video

Similar products you might be interested in

open-in-new Compare alternates
Pin-for-pin with same functionality to the compared device
TPS51225 ACTIVE 5.5-V to 24-V, dual-synchronous buck controller with 5-V and 3.3-V LDOs Lower current equivalent part.
TPS51275C ACTIVE 5.5-V to 24-V, dual-synchronous buck controller with VREG5 always-on LDO Wider operating temperature range and a narrow switching frequency range.

Technical documentation

star =Top documentation for this product selected by TI
No results found. Please clear your search and try again.
View all 2
Type Title Date
* Data sheet Ultra-Low Quiescent (ULQ) Dual Synchronous Step-Down Controller with 5V/ 3.3V datasheet 12 Apr 2013
Application note Mosfet Driver Circuit Design Guide for TPS512xx (Rev. A) 01 Apr 2019

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Simulation model

TPS51285B Unencrypted PSpice Transient Model Package (Rev. A)

SLVM846A.ZIP (87 KB) - PSpice Model
Package Pins CAD symbols, footprints & 3D models
WQFN (RUK) 20 Ultra Librarian

Ordering & quality

Information included:
  • RoHS
  • REACH
  • Device marking
  • Lead finish/Ball material
  • MSL rating/Peak reflow
  • MTBF/FIT estimates
  • Material content
  • Qualification summary
  • Ongoing reliability monitoring
Information included:
  • Fab location
  • Assembly location

Support & training

TI E2E™ forums with technical support from TI engineers

Content is provided "as is" by TI and community contributors and does not constitute TI specifications. See terms of use.

If you have questions about quality, packaging or ordering TI products, see TI support. ​​​​​​​​​​​​​​

Videos