MIC4721 Datasheet, PDF (1/19 Pages) Micrel Semiconductor – 1.5A 2MHz Integrated Switch Buck Regulator

MIC4721
1.5A 2MHz Integrated Switch
Buck Regulator
General Description
Features
The Micrel MIC4721 is a high efficiency PWM buck (step-
down) regulators that provides up to 1.5A of output
current. The MIC4721 operates at 2MHz and has
proprietary internal compensation that allows a closed loop
bandwidth of over 200KHz.
The low on-resistance internal p-channel MOSFET of the
MIC4721 allows efficiencies up to 94%, reduces external
components count and eliminates the need for an
expensive current sense resistor.
The MIC4721 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 MIC4721 is available in the 10-pin MSOP package
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.
• 2.7 to 5.5V supply voltage
• 2MHz PWM mode
• Output current to 1.5A
• Up to 94% efficiency
• 100% maximum duty cycle
• Adjustable output voltage option down to 1V
• Ultra-fast transient response
• Ultra-small external components
Stable with a 1µH inductor and a 4.7µF output capacitor
• Fully integrated 1.5A MOSFET switch
• Micropower shutdown
• Power Good pin
• Thermal shutdown and current limit protection
• Pb-free 10-pin MSOP package
• –40°C to +125°C junction temperature range
Applications
• FPGA/DSP/ASIC applications
• General point of load
• Broadband communications
• DVD/TV recorders
• Point of sale
• Printers/Scanners
• Set top boxes
• Computing peripherals
• Video cards
___________________________________________________________________________________________________________
Typical Application
1.5A 2MHz Buck Regulator
5V_IN to 3.3V_O Efficiency
94
92
90
88
86
84
82
80
78
760 _{0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6}
OUTPUT CURRENT (A)
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel [phone] • fax + 1 [phone] • http://www.micrel.com
May 2007
1
M9999-052907-A