General Description

The AOZ2231CQI-21 is an I2C controllable, high

efficiency, easy-to-use DC-DC synchronous buck

regulator capable of operation from a 6.5V to 28V input

bus. Ability to control the output voltage using the I2C bus

simplifies converter design for microprocessors or SoCs

that require dynamic voltage scaling or voltage

margining. The device is capable of supplying 4A of

continuous output current with an output voltage

adjustable from 0.7V to 0.92599V (±2.0).

The AOZ2231CQI-21 integrates an internal linear

regulator to generate 5.3V VCC from input. If input

voltage is lower than 5.3V, the linear regulator operates

at low drop output mode, which allows the VCC voltage is

equal to input voltage minus the drop-output voltage of

the internal linear regulator.

A proprietary constant on-time PWM control with input

feed-forward results in ultra-fast transient response while

maintaining relatively constant switching frequency over

the entire input voltage range.

The devices feature multiple protection functions such as

VCC under-voltage lockout, cycle-by-cycle current limit,

output over-voltage protection, short-circuit protection,

and thermal shutdown.

The AOZ2231CQI-21 is available in a 4mm×4mm QFN-

22L package and is rated over a -40°C to +85°C ambient

temperature range.

特性 Features

? Wide input voltage range

– 6.5V to 28V

? 4A continuous output current

? Output voltage adjustable from 0.7V to 0.92599V in

7.29mV

? ±2.0 output voltage accuracy for I2C control

? Low RDS(ON) internal NFETs

– 28m? high-side

– 28m? low-side

? Constant On-Time with input feed-forward

? Selectable PFM Light-Load Operation

? Ceramic capacitor stable

? Power Good output

? I2C address programming

? Integrated bootstrap diode

? Cycle-by-cycle current limit

? Short-circuit protection

? Over voltage protection

? Thermal shutdown

? Thermally enhanced 4mm x 4mm QFN-22L package

Applications

? Portable computers

? Compact desktop PCs

? Servers

? Graphics cards

? Set-top boxes

? LCD TVs

? Cable modems

? Point-of-load DC/DC converters

? Telecom/Networking/Datacom equipment