1 Features

? Functional Safety-Capable

– Documentation available to aid functional safety

system design

? Configured for rugged industrial applications

– Wide Input voltage range: 4 V to 36 V

– 4-A or 5-A continuous output current

– ±1.0 tolerance voltage reference at room

temperature

– Minimum switching-on time: 75 ns (typical)

– Low Quiescent current: 25 μA

– Adjustable Frequency: 200 kHz to 1.1 MHz

– Frequency spread spectrum (PFM variant)

– Protection features

? Precision enable input

? Open-drain PGOOD

? VIN undervoltage lockout (UVLO)

? Cycle-by-cycle current limiting

? Short-circuit protection with hiccup mode

? Thermal shutdown

– Low dropout mode operation

– Junction temperature range: –40°C to 150°C

? Small solution size and ease of use

– Integrated synchronous rectification

– Internal compensation for ease of use

– WSON-12 package

? Various options in pin-to-pin compatible package

– PFM and forced PWM (FPWM) options

? Create a custom design using the LMR5144x0

with the WEBENCH? Power Designer

2 Applications

? Major appliances

? PLC, DCS, and PAC

? Test and measurement instrumentation

? Power delivery

3 Description

The LMR514x0 is a wide-VIN, easy-to-use

synchronous buck converter capable of driving up to

4-A or 5-A load current. With a wide input range of 4

V to 36 V, the device is suitable for a wide range of

industrial applications for power conditioning from an

unregulated source.

The LMR514x0 features adjustable switching

frequency from 200 kHz to 1.1 MHz with an external

resistor, which provides the flexibility to optimize either

efficiency or external component size. The device has

PFM version to realize high efficiency at light load and

FPWM version to achieve constant frequency, and

small output voltage ripple over the full load range.

Soft-start and compensation circuits are implemented

internally which allows the device to be used with

minimum external components.

The device has built-in protection features, such as

cycle-by-cycle current limit, hiccup mode short-circuit

protection, and thermal shutdown in case of excessive

power dissipation. The LMR514x0 is available in

WSON-12 package.