1 Features

• AEC-Q100 qualified for automotive applications

– Temperature grade 1: −40ºC ≤ TA≤ 150ºC

• Wide input voltage operating range: 4.4V to 65V

with 20mV/step

• Synchronous buck-boost DC/DC controller with

NFET drivers

– Adjustable fSW from 200kHz to 600kHz

– Switching frequency dithering for EMI noise

reduction (DRSS)

– Optional synchronization to external clock

– Integrated loop compensation with soft start

– Selectable PFM operation for light load

efficiency improvement (PFM or forced PWM

option)

– Optional gate driver supply input for optimized

efficiency

• Support USB-PD Extended Power Range (EPR) in

forward and reverse power direction

– Adjustable output voltage regulation from 3.3V

to 60V with 20mV/step

– Adjustable input and output current regulation

(RAC_SNS, ROUT_SNS) from 400mA to 20A

with 50mA/step using 5mΩ resistor

• Bypass mode for highest efficiency with VOUT =

VAC

• Buck-only mode

• High accuracy

– ±2% output voltage regulation

– ±3% output/input current regulation

– ±2% input voltage regulation

• I2C controlled for optimal system performance with

resistor-programmable option

– Hardware adjustable input and output current

limits

• Integrated 16-bit ADC for voltage, current, and

temperature monitoring

• High safety integration

– Adjustable input overvoltage and undervoltage

protection

– Output overvoltage and overcurrent protection

– Thermal shutdown

• Status outputs

– Input power present status (PG)

– Switcher operation status (STAT)

• Package

– 36-pin 5mm × 6mm QFN with wettable flanks

2 Applications

• Low voltage battery system

• Automotive USB charging

• Central compute unit multidomain

• ADAS domain controller

• Infotainment & cluster

3 Description

BQ25858-Q1, BQ25858B-Q1 are automotive grade,

wide input voltage, bidirectional switched-mode buckboost

controllers. The devices offer high-efficiency

regulation over a wide voltage range with output

CC-CV control. The devices integrate all the loop

compensation for the buck-boost converter, thereby

providing a high density solution with ease of use.

In reverse mode, the devices draw power from the

output supply and regulate the input terminal voltage

with an added constant current loop for protection.

Besides the I2C host-controlled mode, the device also

supports programmable hardware limits. Input current,

and output current regulation targets can be set with

single resistor on the IIN, and IOUT pins, respectively.

By default, the device is programmed to provide 5V

output, and the target output voltage can be adjusted

via the VOUT_REG register bits.