1 Features

• 4V to 18V input voltage without external bias

• 2.7V to 18V input voltage with external bias

• 0.4V to 5.5V output voltage

• Supports 25A single-phase

• Rdson_HS = 2.6mΩ, Rdson_LS = 1mΩ

• 400kHz to 2MHz operating frequency (four

discrete settings through pin-strap, additional

settings through PMBus®)

• PMBus programmable

– Revision 1.5 compliant with PASSKEY security

feature

– Input voltage, output voltage, output current,

temperature telemetry

– Programmable overcurrent, overvoltage,

undervoltage, overtemperature protections

– Extended write protection feature

– Non-volatile memory to store configuration

settings

• Two methods for programming the output voltage

– Internal resistor divider (discrete settings) with

boot-up voltage selected by pin-strapping

– External resistor divider (continuous settings)

with boot-up voltage selected by VBOOT

• Precision voltage reference and differential remote

sense for high output accuracy

– +/– 0.5% DAC accuracy from 0°C to 85°C

junction

– +/– 1% VOUT tolerance from –40°C to 125°C

junction

• Selectable FCCM/DCM in single phase only

• Start-up without PMBus communication through

pin-strapping

• Safe start-up into prebiased output

• 0.5ms to 16ms programmable soft-start time

• D-CAP4 control topology with fast transient

response, supporting all ceramic output capacitors

• Programmable internal loop compensation

• Selectable cycle-by-cycle valley current limit

• Open-drain power-good output

2 Applications

• Server and cloud-computing POLs

• Hardware accelerator

• Network interface card

3 Description

The TPS546B26 device is a highly integrated, buck

converter with D-CAP4 control topology for fast

transient response. All programmable parameters

can be configured by the PMBus interface and

stored in NVM as the new default values to

minimize the external component count. Pin-strap

options allow for DCM or FCCM, overcurrent

limit, fault response, internal or external feedback

resistor, output voltage selection or range, switching

frequency, and compensation.

The PMBus interface with 1MHz clock support

gives a convenient, standardized digital interface for

configuration as well as telemetry of key parameters

including output voltage, output current, and internal

die temperature. Response to fault conditions can

be set to restart, latch off, or ignore, depending on

system requirements.

The TPS546B26 has an option to overdrive the

internal 5V LDO with an external 5V supply through

the VDRV and VCC pins to improve efficiency, reduce

power dissipation, and enable start-up with a lower

input voltage.

The TPS546B26 is a lead-free device and is RoHS

compliant without exemption.