TPS5120

DUAL OUTPUT, TWOPHASE SYNCHRONOUS BUCK DC/DC CONTROLLER

SLVS278E – AUGUST 2000 – REVISED MARCH 2003

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POST OFFICE BOX 655303

Out of Phase

Efficiency Under Light Loads

95% Efficiency

Protection for Each Channel

Current

Softstart Capacitor Values.

Circuitry

description

The TPS5120 is a dual channel, high-efficiency synchronous buck controller where the outputs run 180 degrees

out of phase, which lowers the input current ripple, thereby reducing the input capacitance cost. The PWM/SKIP

pin allows the operating mode to switch from PWM mode to skip mode under light load conditions. The skip

mode enables a lower operating frequency and shortens the pulse width to the low-side MOSFET, increasing

the efficiency under light load conditions. These two modes, along with synchronous-rectifier drivers, dead time,

and very low quiescent current, allow power to be conserved and the battery life to be extended under all load

conditions. The 1.5 A (typical) high-side and low-side MOSFET drivers on-chip are designed to drive less

expensive N-channel MOSFETs. The resistorless current protection and fixed high-side driver voltage simplify

the power supply design and reduce the external parts count. Each channel is independent, offering a separate

controller, overcurrent protection, and standby control. Sequencing is flexible and can be tailored by choosing

different softstart capacitor values. Other features, such as undervoltage lockout, power good, overvoltage,

undervoltage, and programmable short-circuit protection promote system reliability.

Copyright

 2002, Texas Instruments Incorporated

PRODUCTION DATA information is current as of publication date.

Products conform to specifications per the terms of Texas Instruments

standard warranty. Production processing does not necessarily include

testing of all parameters.

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.

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INV1

FB1

SOFTSTART1

PWM/SKIP

CT

5V_STBY

GND

REF

STBY1

STBY2

FLT

POWERGOOD

SOFTSTART2

FB2

INV2

LH1

OUT1_u

LL1

OUT1_d

OUTGND1

TRIP1

TRIP2

VREF5

REG5V_IN

OUTGND2

OUT2_d

LL2

OUT2_u

LH2

DBT PACKAGE

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