TPS51275_17 Datasheet, PDF (1/31 Pages) Texas Instruments – Dual Synchronous, Step-Down Controller with 5-V and 3.3-V LDOs

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 R_DS(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, D-
CAP™ 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 20-
pin, 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