1 Features
• Functional Safety-Capable
– Documentation available to aid functional safety
system design
• Configured for rugged industrial applications:
– Wide input voltage range: 4V to 36V
– Continuous output current: 2.5A or 3.5A
– ±1.0% tolerance voltage reference at room
temperature
– Minimum switching-on time: 75ns (typical)
– Low quiescent current: 25μA
– Adjustable frequency: 200kHz to 1.1MHz
– Frequency spread spectrum
– 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
• Small design size and ease of use
– Integrated synchronous rectification
– Internal compensation for ease of use
– WSON-12 package
• PFM and FPWM options in pin-to-pin compatible
package
• Create a custom design using the LMR514x5 with
the WEBENCH® Power Designer

2 Applications
• Major appliances
• PLC, DCS, and PAC
• Test and measurement instrumentation
• Power delivery

3 Description
The LMR514x5 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
4V to 36V, the device is designed for a wide range of
industrial applications for power conditioning from an
unregulated source.
The LMR514x5 features adjustable switching
frequency from 200kHz to 1.1MHz with an external
resistor, which provides the flexibility to optimize either
efficiency or external component size. The device
has pulse frequency modulation (PFM version) to
realize high efficiency at light load, and forced pulse
width modulation (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 LMR514x5 is available in a
WSON-12 package.