General Description
The Micrel MIC22400 is a high-efficiency, 4A integrated switch synchronous buck (step-down) regulator. The MIC22400 is optimized for highest efficiency, achieving over 90% efficiency while still switching at 1MHz over a broad load range. The ultra-high-speed control loop keeps the output voltage within regulation even under extreme transient load swings commonly found in FPGAs and lowvoltage ASICs.

Features
• Input voltage range: 2.6V to 5.5V
• Output voltage adjustable down to 0.7V
• Output load current up to 4A
• Full sequencing and tracking ability
• Power-On-Reset (POR)
• Efficiency > 90% across a broad load range
• Programmable frequency 300kHz to 4MHz
• Easy Ramp Control™ (RC) compensation
• Ultra-fast transient response
• 100% maximum duty cycle
• Fully-integrated MOSFET switches
• Micropower shutdown
• Thermal-shutdown and current-limit protection
• 20-pin 3mm x 4mm MLF®
• 20-pin ePad TSSOP
• –40°C to +125°C junction temperature range

Applications
• High power density point-of-load conversion
• Servers and routers
• DVD recorders
• Computing peripherals
• Base stations
• FPGAs, DSP and low-voltage ASIC power