Document
TPS51275, TPS51275B, TPS51275C
www.ti.com
SLUSB45B – JUNE 2012 – REVISED MARCH 2013
Dual Synchronous, Step-Down Controller with 5-V and 3.3-V LDOs
FEATURES
1
APPLICATIONS
•2 Input Voltage Range: 5 V to 24 V
• Notebook Computers
• 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 300-kHz and 355-kHz Frequency Setting • Auto-skip Light Load Operation (TPS51275, and TPS51275C) • OOA Light Load Operation (TPS51275B) • 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
• Tablet Computers
DESCRIPTION
The TPS51275, TPS51275B and TPS51275C are cost-effective, dual-synchronous buck controllers targeted for notebook system-power supply solutions. It provides 5-V and 3.3-V LDOs and requires few external components. The 260-kHz VCLK output can be used to drive an external charge pump, generating gate drive voltage for the load switches without reducing the main converter efficiency. The TPS51275, TPS51275B and TPS51275C supports high efficiency, fast transient response and provides a combined power-good signal. Adaptive on-time, DCAP™ control provides convenient and efficient operation. The device operates with supply input voltage ranging from 5 V to 24 V and supports output voltages of 5.0 V and 3.3 V. The TPS51275, TPS51275B and TPS51275C are available in a 20pin, 3 mm x 3 mm, QFN package and is specified from –40°C to 85°C.
• Non-Latch UVLO and OTP Protection
• 20-Pin, 3 mm x 3 mm, QFN (RUK) NEED SOME SPACE
ORDERING INFORMATION(1)
ORDERABLE DEVICE NUMBER
ENABLE FUNCTION
SKIP MODE
ALWAYS On-LDO
PACKAGE
OUTPUT SUPPLY
QUANTITY
TPS51275RUKR TPS51275RUKT
Auto-skip
VREG3
Tape and Reel Mini reel
3000 250
TPS51275BRUKR TPS51275BRUKT TPS51275CRUKR TPS51275CRUKT
EN1 and EN2
OOA Auto-skip
VREG3 and VREG5
PLASTIC Quad Flat Pack
Tape and Reel Mini reel
Tape and Reel Mini reel
3000 250 3000 250
(1) For the most current package and ordering information see the Package Option Addendum at the end of this document, or see the TI website at www.ti.com.
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. D-CAP is a trademark of Texas Instruments.
2
PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of the Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters.
Copyright © 2012–2013, Texas Instruments Incorporated
TPS51275, TPS51275B, TPS51275C
SLUSB45B – JUNE 2012 – REVISED MARCH 2013
www.ti.com
These dev.