1 Features

• Functional Safety-Capable

– Documentation available to aid functional safety

system design

• Designed for rugged industrial applications:

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

– Input transient protection up to 70 V

– Wide input voltage range: 3.0 V (falling

threshold) to 65 V

– Minimized switch node ringing to reduce EMI

– Adjustable and fixed output 3.3-V and 5-V

voltage options available

• Suited for scalable industrial power supplies:

– Pin compatible with LMR36503 (65 V, 300 mA)

and LMR36506 (65 V, 600 mA)

– Adjustable switching frequency: 200 kHz to

2.2 MHz with RT pin variant

• Minimized solution size and cost:

– Ultra-small, 2-mm × 2-mm HotRod™ package

• High efficiency across load range with low power

dissipation:

– Greater than 80 peak efficiency at 1 MHz

(3.3-V VOUT)

2 Applications

• Factory automation: field transmitters and process

sensors

• Building automation: HVAC and fire safety

notification and detectors

• Appliances: garden and power tools

• Portable electronics: headphones and earbuds

3 Description

The LMR3650x is the industry smallest 65-V, 150-mA,

100-mA synchronous step-down DC/DC converter in

4-mm2 HotRod package. This easy-to-use converter

can handle input voltage transients up to 70 V,

provide excellent EMI performance and supports

fixed, 3.3 V, 5 V and other adjustable output voltages.

The LMR3650x uses the peak current mode control

architecture with internal compensation to maintain

stable operation with minimal output capacitance. The

LMR3650x with the right resistor selection from the

RT pin to ground can be externally programmed to

any desired switching frequency of operation over a

wide range from 200 kHz to 2.2 MHz. The precision

EN/UVLO feature allows precise control of the device

during the start-up and shutdown. The PGOOD flag,

with built-in glitch filter and delayed release, offers

a true indication of the system status, eliminating

the requirement for an external voltage supervisor.

The compact solution size and rich feature set of

LMR3650x simplifies implementation for a wide range

of industrial applications.