MIC4722 Datasheet, PDF (1/20 Pages) Micrel Semiconductor – 3mm x 3mm 2.7MHz 3A PWM Buck Regulator

MIC4722
3mm x 3mm 2.7MHz 3A PWM Buck Regulator
General Description
The Micrel MIC4722 is a high efficiency PWM buck (step-
down) regulator that provides up to 3A of output current.
The MIC4722 operates at 2.7MHz that makes it suitable
for next generation XDSL modems requiring operating
frequencies in excess of 2.4MHz and has proprietary
internal compensation that allows a closed loop bandwidth
of over 200KHz.
The low on-resistance internal p-channel MOSFET of the
MIC4722 allows efficiencies over 92%, reduces external
components count and eliminates the need for an
expensive current sense resistor.
The MIC4722 operates from 2.7V to 5.5V input and the
output can be adjusted down to 1V. The devices can
operate with a maximum duty cycle of 100% for use in low-
dropout conditions.
The MIC4722 is available in the exposed pad 12-pin
3mm x 3mm MLF^® package with a junction operating
range from –40°C to +125°C.
Features
• 2.7 to 5.5V supply voltage
• 2.7MHz PWM mode
• Output current to 3A
• >92% efficiency
• 100% maximum duty cycle
• Adjustable output voltage option down to 1V
• Ultra-fast transient response
• Ultra-small external components
Stable with a 0.47µH inductor and a 4.7µF output
capacitor
• Fully integrated 3A MOSFET switch
• Micropower shutdown
• Thermal shutdown and current limit protection
• Pb-free 12-pin 3mm x 3mm MLF^® package
• –40°C to +125°C junction temperature range
Applications
• 5V or 3.3V Point of Load Conversion
• Telecom/Networking Equipment
• Set Top Boxes
• Storage Equipment
• Video Cards
Typical Application
MIC4722
3A 2.7MHz Buck Regulator
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
September 2007
M9999-090507-B