MIC22400_11 Datasheet, PDF (1/28 Pages) Micrel Semiconductor – 4A Integrated Switch Synchronous Buck Regulator with Frequency Programmable up to 4MHz

MIC22400
4A Integrated Switch Synchronous
Buck Regulator with Frequency
Programmable up to 4MHz
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 low-
voltage ASICs. The output voltage can be adjusted down
to 0.7V to address all low-voltage power needs. The
MIC22400 gives a full range of sequencing and tracking
options. The EN/DLY pin combined with the Power-On-
Reset (POR) pin allows multiple outputs to be sequenced
in any way on turn-on and turn-off. The Ramp Control™
(RC) pin allows the device to be connected to another
MIC22400 family of products to keep the output voltages
within a certain ΔV on start-up.
The MIC22400 is available in a 20-pin 3mm x 4mm MLF^®
and thermally-enhanced 20-pin ePad TSSOP with a
junction operating range from –40°C to +125°C.
Data sheets and support documentation can be found on
Micrel’s web site at: www.micrel.com.
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
Typical Application
MIC22400 4A Synchronous Buck Regulator
Sequencing & Tracking
Ramp Control is a trademark of Micrel, Inc.
MLF and MicroLeadFrame are registered trademarks of Amkor Technology, Inc.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel [phone] • fax + 1 [phone] • http://www.micrel.com
June 2011
M9999-061511-F