General Description
The AOZ22557QI is a high-efficiency, easy-to-use DC/DC
synchronous buck regulator that operates up to 25 V. The
device is capable of supplying 15 A of continuous output
current with an output voltage adjustable down to 0.6 V
(±1.0%).
The AOZ22557QI integrates an internal linear regulator to
generate 5.3 V VCC from input. If input voltage is lower than
5.3 V, 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. A low 80 ns minimum on-time
enables very low output voltages at ultra-high operating
frequencies.
Integrated AC ripple injection enables all-ceramic low ESR
output filter capacitors and smaller PCB footprint with no
external components needed.
Selectable PFM mode optimizes light load efficiency while
forced PWM mode maintains constant frequency for lower
harmonic noise.
The device features 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 AOZ22557QI is available in a 4mm×4mm QFN-30L
package and is rated over a -40°C to +85°C ambient
temperature range.

Features
• Wide input voltage range
- 6.5 V to 25 V
• 15 A continuous output current
• Output voltage adjustable down to 0.6 V (±1.0%)
• Low RDS(ON) internal NFETs
- 11 mΩ high-side
- 4 mΩ low-side
• Internal LDO
• Constant On-Time with input feed-forward
• Programmable on-time up to 3.5 μs and down to 80 ns
• Programmable Switching Frequency Range up to 1MHz
(For 12VIN to 1VOUT)
• Selectable PFM or forced PWM light load operation
• Ceramic capacitor stable
• Remote Sense
• Adjustable current limit setting
• Adjustable soft start
• Power Good output
• Integrated bootstrap diode
• Under-voltage protection and over-voltage protection
• Cycle-by-cycle current limit
• Short-circuit protection
• Thermal shutdown
• Thermally enhanced 30-pin 4mm × 4mm QFN

Applications
• Compact PCs and gaming systems
• Set-top boxes and LCD TVs
• Server & Storage systems
• Datacom and networking
• Embedded computing
• Point-of-load DC/DC converters