1 Features

• AEC-Q100 qualified for automotive applications

– Temperature grade 1: –40°C to +125°C TA

• Functional Safety-Capable

– Documentation available to aid functional safety

system design

• Wide input operating range for car and portable

battery applications

– 3.5-V to 45-V Operating range

– 2.97-V to 16-V When BIAS = VCC

– Minimum boost supply voltage 1.5 V when

BIAS ≥ 3.5 V

– Input transient protection up to 50 V

• Minimized battery drain

– Low shutdown current (IQ ≤ 2.6 μA)

– Low operating current (IQ ≤ 480 μA)

• Small solution size and low cost

– Maximum switching frequency of 2.2 MHz

– 12-Pin WSON package (3 mm × 2 mm) with

wettable flanks

– Integrated error amplifier allows primary-side

regulation without optocoupler (flyback)

– Minimized undershoot during cranking (startstop

application)

• Higher efficiency with low-power dissipation

– 100-mV ±7 Low current limit threshold

– Strong 1.5-A peak standard MOSFET driver

– Supports external VCC supply

• Avoid AM band interference and crosstalk

– Optional clock synchronization

– Dynamically programmable switching frequency

from 100 kHz to 2.2 MHz

• Integrated protection features

– Constant peak current limiting over input

voltage

– Optional hiccup mode short-circuit protection

(see the Device Comparison Table)

– Programmable line UVLO

– OVP protection

– Thermal shutdown

• Accurate ±1 accuracy feedback reference

• Programmable extra slope compensation

• Adjustable soft start

• PGOOD indicator

• Create a custom design using the LM5155x with

the WEBENCH® power designer

2 Applications

• Automotive start-stop application

• High voltage LiDAR power supply

• Multiple-output flyback without optocoupler

• Automotive rear-lights LED bias supply

• Wide input boost, SEPIC, flyback power module

• Portable speaker application

• Battery-powered boost, SEPIC, flyback

3 Description

The LM5155x-Q1 (LM5155-Q1 and LM51551-Q1) is a

wide input range, non-synchronous boost controller

that uses peak current mode control. The device can

be used in boost, SEPIC, and flyback topologies.

The LM5155x-Q1 can start up from a 1-cell battery

with a minimum of 2.97 V if the BIAS pin is connected

to the VCC pin. It can operate with the input supply

voltage as low as 1.5 V if the BIAS pin is greater than

3.5 V.