1 Features

• Wide input voltage range

– 3.35V to 36V rising edge

– 2.7V to 36V falling edge

– 42V absolute maximum

• Integrated 132mΩ and 75mΩ MOSFETs

• Optimized for low EMI requirements:

– Dual Random Spread Spectrum reduces peak

emissions

– Pin selectable FPWM mode for constant

frequency at light loads and FSW

synchronization with MODE/SYNC pin

– Adjustable FSW: 200kHz – 2.2MHz with RT pin

• Miniature design size and low component cost:

– 2.6mm × 2.6mm enhanced HotRod™ QFN

package with wettable flanks and internal lead

free solder

– Internal control loop compensation

2 Applications

• Supports defense and aerospace applications

– Controlled baseline

– One assembly and test site

– One fabrication site

– Junction temperature supports (–55ºC to

150ºC) temperature range

– Extended product life cycle

– Extended product-change notification

– Product traceability

• Medical

• Test and measurement

• Motor drives

3 Description

The LMR66430-EP is a small 36V, 3A, synchronous

step-down DC/DC converter with an enhanced

HotRod QFN package. This easy-to-use converter

supports a wide input voltage range of 2.7V to 36V

(after start-up or after operating) with transients up to

42V.

The LMR66430-EP is specifically designed to meet

low standby power requirements for always-on,

applications. Auto mode enables frequency foldback

when operating at light loads, allowing high light load

efficiency. A seamless transition between pulse width

modulation (PWM) and pulse frequency modulation

(PFM) modes along with very low MOSFET ON

resistances makes sure there is exceptional efficiency

across the entire load range. The control architecture

(peak current mode) and feature set are an excellent

choice for an ultra-small design size with minimal

output capacitance. The device minimizes input filter

size by using dual-random spread spectrum (DRSS),

a low-EMI enhanced HotRod QFN package, and

an optimized pinout. The MODE/SYNC and RT pin

variants can be used to set or synchronize the

frequency to avoid noise sensitive frequency bands.

There are NC pins between critical high voltage pins,

reducing potential short circuits between pins. The

rich feature set of the LMR66430-EP is designed to

simplify implementation for a wide range of industrial

end equipment.