1 Features

• AEC-Q100 qualified for automotive applications

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

• Functional Safety-Capable

– Documentation available to aid functional safety

system design

• Input voltage 4.5V to 42V

– Minimum 2.5V for V(BIAS) ≥ 4.5V or VOUT ≥ 6V

• Output Voltage 6V to 60V

– 2% accuracy, internal feedback resistors

– Bypass operation for VI > VOUT

– Dynamic output voltage tracking

• Digital PWM tracking (DTRK)

• Analog tracking (ATRK)

– Overvoltage protection (64V, 50V, 35V, 28.5V)

• Low shutdown IQ of 2μA typ. (5μA maximum)

• Low operating IQ of 1.4mA typ. (2mA maximum)

• Stacking with interleaved multiphase operation

– Up to 4-phases without external clock

• Switching frequency from 100kHz to 2.2MHz

– Synchronization to external clock (SYNCIN)

– Dynamically selectable switching modes

(FPWM, diode emulation)

– Spread spectrum (DRSS)

• Selectable dead time (18ns to 200ns)

• Current sense resistor or DCR sensing

• Average inductor current monitor

• Average input current limit

– Programmable current limit

– Selectable delay time

• Power-good indicator

• Programmable VI undervoltage lockout (UVLO)

• Lead-less VQFN-32 package with wettable flanks

2 Applications

• High-end audio power supply

• Voltage stabilizer module

• Start-stop application

3 Description

The LM5125-Q1 is a stackable, multiphase,

synchronous, boost controller. The device provides

a regulated output voltage for lower or equal input

voltage also supporting VI to VOUT bypass mode to

save power. Two devices can be stacked with or

without external clock.

VOUT can be dynamically programmed using the

digital or analog ATRK/DTRK function. VI can be as

low as 2.5V after start-up as the internal VCC supply

is automatically switched from VBIAS to VOUT for VBIAS

< 4.5V. The fixed switching frequency is set between

100kHz and 2.2MHz through a resistor on the RT pin

or the SYNCIN clock. The switching modes, FPWM,

or diode emulation can be changed during operation.

The implemented protections peak current limit,

average input current limit, average inductor current

monitor, over and undervoltage protection, or the

thermal shutdown protect the device and the

application.