1 Features

• Fixed-frequency, internally compensated advanced

current mode (ACM) control

• Integrated 6.5-mΩ and 2-mΩ MOSFETs

• 4-V to 18-V input voltage range

• 0.5-V to 7-V output voltage range

• True differential remote sense amplifier (RSA)

• Three selectable PWM ramp options to optimize

the control loop performance

• Five selectable switching frequencies: 500 kHz,

750 kHz, 1 MHz, 1.5 MHz, and 2.2 MHz

• Synchronizable to an external clock

• 0.5 V, ±1 voltage reference accuracy over full

temperature range

• Selectable soft start times: 1 ms, 2 ms, 4 ms, and

8 ms

• Monotonic start-up into prebiased outputs

• Selectable current limits to support 20-A and 16-A

operation

• Enable with adjustable input undervoltage lockout

• Power-good output monitor

• Output overvoltage, output undervoltage, input

undervoltage, overcurrent, and overtemperature

protection

• –40°C to 150°C operating junction temperature

• 2.5-mm × 4.5-mm, 17-pin WQFN-HR package with

0.5-mm pitch

• Lead-free (RoHS compliant)

• Pin compatible with the TPS543A26 and

TPS543A22

• PSpice and SIMPLIS models available

2 Applications

• Wireless and wired communications infrastructure

equipment

• Optical and fiber networks

• Test and measurement

• Medical and healthcare

3 Description

The TPS543B22 is a high-efficiency 18-V, 20-A

synchronous buck converter employing an internally

compensated, fixed-frequency advanced current

mode (ACM) control architecture, which while always

operating under FCCM, generates output voltages

from 0.5 V to 7 V. The device is capable of

providing high efficiency while operating at a switching

frequency up to 2.2 MHz, making it optimal for

designs requiring a small solution size. The fixed

frequency controller can operate from 500 kHz to

2.2 MHz and can be synchronized to an external

clock using the SYNC pin. Additional features include

a high accuracy voltage reference, two-wire remote

sense, selectable soft start times, monotonic startup

into prebiased outputs, selectable current limits,

adjustable UVLO through the EN pin, and a full suite

of fault protections.

The TPS543B22 is available in a small 2.5-mm × 4.5-

mm HotRod™ WQFN-FCRLF package.