1 Features

• Functional Safety-Capable

– Documentation available to aid functional safety

system design

• Configured for rugged industrial applications:

– 4.3V to 60V input voltage range

– 2.5A or 3.5A continuous output current

– Low operating quiescent current of 29μA

– 70ns minimum switching on time

– 400kHz amd 1.1MHz switching frequency

– Frequency spread spectrum (PFM variant)

– –40°C to 150°C junction temperature range

– 96% maximum duty cycle

– Monotonic start-up with prebiased output

– Short-circuit protection with hiccup mode

– Precision enable

– ±1% tolerance voltage reference

• Small design size and ease of use:

– Integrated synchronous rectification

– Internal compensation for ease of use

– SOT-23 package

• Various options in pin-to-pin compatible package

– PFM and forced PWM (FPWM) options

• Create a custom design using the LMR516x5 with

the WEBENCH® Power Designer

2 Applications

• Major appliances

• PLC, DCS, and PAC

• Smart meters

• General purpose wide VIN power supplies

3 Description

The LMR516x5 is a wide-VIN, easy-to-use,

synchronous buck converter capable of driving up to

2.5A or 3.5A load current. With a wide input range of

4.3V to 60V, the device is designed for a wide range

of industrial applications for power conditioning from

an unregulated source.

The LMR516x5 operates at 400kHz or 1.1MHz

switching frequency to support use of relatively small

inductors for an optimized design size. The device

has a pulse frequency modulation (PFM version) to

realize high efficiency at light load and a forced pulse

width modulation (PFM version) to achieve constant

frequency and small output voltage ripple over the full

load range, soft-start and compensation circuits are

implemented internally, which allow the device to be

used with minimal 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.