1 Features

• AEC-Q100-qualified for automotive applications:

– Device temperature grade 0: –40°C to +150°C,

TA

• > 70 efficiency at 5mA

– 4μA IQ (switching) at 24VIN to 3.3VOUT (fixed

output option)

• Miniature design size and low component cost

– 2mm × 2mm HotRod™ package with wettable

flanks

– Internal compensation

• Designed for automotive applications:

– Junction temperature range –40°C to +175°C

– Pseudo-random spread spectrum compatible

with CISPR 25 EMI standard

– Wide input voltage range: 3V (falling threshold)

to 65V

– Adjustable and 3.3V fixed output voltage

options available

– Synchronizable with MODE/SYNC pin variant

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

variant

– Functional Safety-Capable

• Documentation available to aid designs

requiring functional safety

– Pin compatible with LMR36503-Q1 (65V,

300mA)

• Create a custom design using the LMR36503E-Q1

with the WEBENCH® Power Designer

2 Applications

• Advanced driver assistance systems (ADAS)

• Body electronics and lighting

• Infotainment and cluster

3 Description

The LMR36503E-Q1 is a 65V, 0.3A synchronous

step-down DC/DC converter in 2mm × 2mm HotRod

package. This easy-to-use converter can handle input

voltage transients up to 70V, provide excellent EMI

performance, and support fixed 3.3V, 5V and other

adjustable output voltages.

The LMR36503E-Q1 uses peak current mode control

architecture with internal compensation and maintains

stable operation with minimal output capacitance.

The wide input operating range of the LMR36503EQ1

helps the device remain functional during a

deep input voltage sag condition, making the device

an excellent choice for automotive applications

withstanding severe cold crank start impulses. The

PGOOD flag in the LMR36503E-Q1 provides precise

indication of the output voltage status, eliminating the

requirement for an external supervisor. A seamless

transition from FPWM to PFM, with an ultra-low

standby quiescent current allows the LMR36503EQ1

to support much higher system efficiency at low

output loads. The MODE/SYNC pin variant helps to

synchronize the LMR36503E-Q1 to an external clock.

With the right resistor selection, the LMR36503E-Q1

RT pin variant can also be externally programmed

to any desired switching frequency of operation. The

rich feature set of the LMR36503E-Q1 is designed

to simplify implementation for a wide range of

automotive end equipments.