General Description

The Micrel MIC22405 is a high efficiency, 4A integrated switch synchronous buck (step-down) regulator. The MIC22405 is optimized for highest efficiency, achieving more than 95 efficiency while still switching at 1MHz. The ultra-high speed control loop keeps the output voltage within regulation even under the extreme transient load swings commonly found in FPGAs and low-voltage ASICs. The output voltage is pre-bias safe and can be adjusted down to 0.7V to address all low-voltage power needs.

Features

• Input voltage range: 2.9V to 5.5V

• Output voltage adjustable down to 0.7V

• Output load current up to 4A

• Safe start-up into a pre-biased output

• Full sequencing and tracking capability

• Power Good output

• Efficiency > 95 across a broad load range

• Programmable frequency 300kHz to 4MHz

• Ultra-fast transient response

• Easy RC compensation

• 100 maximum duty cycle

• Fully-integrated MOSFET switches

• Thermal shutdown and current-limit protection

• 20-pin 3mm x 4mm MLF®

• –40°C to +125°C junction temperature range

Applications

• High power density point-of-load conversion

• Servers, routers, and base stations

• DVD recorders / Blu-ray players

• Computing peripherals

• FPGAs, DSP and low voltage ASIC power