MIC4720
3mm x 3mm 2.0MHz 2A Integrated
Switch Buck Regulator
General Description
The Micrel MIC4720 is a high efficiency PWM buck (step-
down) regulator that provides up to 2A of output current.
The MIC4720 operates at 2.0MHz and has proprietary
internal compensation that allows a closed loop bandwidth
of over 200KHz.
The low on-resistance internal p-channel MOSFET of the
MIC4720 allows efficiencies over 92%, reduces external
components count and eliminates the need for an
expensive current sense resistor.
The MIC4720 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 MIC4720 is available in the exposed pad 12-pin
3mm x 3mm MLF
®
and 10-pin ePad MSOP package with a
junction operating range from –40°C to +125°C.
Features
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2.7 to 5.5V supply voltage
2.0MHz PWM mode
Output current to 2A
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 2A 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
Pb-free 10-pin ePad MSOP package
FPGA/DSP/ASIC applications
General point of load
Broadband communications
DVD/TV recorder
Point of Sale
Printers/Scanners
Set Top Boxes
Computing Peripherals
Video Cards
Applications
Typical Application
100
95
EFFICIENCY (%)
MIC4720
3.3V
OUT
Efficiency
V
IN
= 4.5V
V = 5.0V
IN
MIC4720
90
85
80
75
70
0
V = 5.5V
IN
1
0.2
0.4
0.6
0.8
1.2
1.4
1.6
OUTPUT CURRENT (A)
2A 2.0MHz Buck Regulator
MLF and
MicroLeadFrame
are registered trademarks of Amkor Technology, Inc.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (
408
) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
May 2007
M9999-051707
1.8
2
65
MICREL [ MICREL SEMICONDUCTOR ]
