1 Features

• Efficiency up to 95% for each switching regulator

• Switching regulator specifications:

– Input voltage range: 4.5 to 18 V

– VOUT range: 0.6 V-90%VIN

– SW1, SW2 IOUT: 4-A max

– SW3, SW4 IOUT: 2-A max

• Prebias start-up algorithm minimizes voltage dip

during start-up

• Internal undervoltage lockout (UVLO), overcurrent

protection (OCP), overvoltage protection (OVP),

and overtemperature protection (OTP)

• AECQ-100 grade 1 option

• Thermally enhanced 7-mm × 7-mm 48-pin, 0.5-mm

pitch VQFN package

• Pin accessible features:

– Adjustable VOUT with external feedback

resistors

– Sequencing control through precision enable

pins for each switcher

– Resistor adjustable PWM switching frequency

from 275 kHz to 2.2 MHz

– Clock sync input and clock output

– Soft-start delay through external capacitor

– Current sharing between SW1 and SW2 and

between SW3 and SW4 allows support of

higher current needs if required

• PMBus runtime control and status

– Runtime voltage positioning through adjustment

of VREF

– Enable and disable of each switcher

– Fault and status monitoring

• User-configurable PMBus/I2C options, saved in

EEPROM

– Power supply turn-on and turn-off sequencing

– Sequencing can be based on fixed time delays

or PGOOD dependence

– Initial voltage positioning through VREF

configuration

– PWM frequency adjustment for each switcher

– Individual PWM phase alignment for each

switcher to minimize ripple and capacitor size

– Adjustable current limit on each regulator

enables size and cost optimization of inductors

– Soft-start time

2 Applications

• Small cellular base stations (BTS) (for example:

picocells and microcells); macro BTS (using

multiple PMUs)

• Power over ethernet (PoE) powered

communications infrastructure equipment

• Automotive infotainment and telematics

• Powering DSP and MCUs

• Industrial and factory automation

• Systems requiring small form factor, highefficiency,

high-ambient operating temperature,

and flexible power management

3 Description

The TPS65400 is an integrated PMU optimized for

applications requiring small form factor and high

power conversion efficiency, enabling small spaceconstrained

equipment with high ambient operating

temperature without cooling. The device provides

high-power efficiency at a system level by enabling

a single stage conversion from an intermediate

distribution bus with an optimized combination of

regulators.