MIC2202

High Efficiency 2MHz Synchronous Buck

Converter 1µF Stable PWM Regulator

MLF and MicroLeadFrame are registered trademarks of Amkor Technology, Inc.

Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (

March 2007

1

M9999-031907

General Description

The Micrel MIC2202 is a high efficiency 2MHz PWM

synchronous buck regulator. The fast 2MHz operation

along with a proprietary compensation scheme allows the

smallest possible external components. The MIC2202 can

operate with a 1µF ceramic output capacitor and a small,

low DC-resistance, 2.2µH inductor, reducing system size

and cost while allowing a high level of efficiency.

The MIC2202 operates from 2.3V to 5.5V input and

features internal power MOSFETs that can supply over

600mA of output current with output voltages down to

0.5V. The MIC2202 implements a constant 2MHz pulse-

width-modu-lation (PWM) control scheme which reduces

noise in sensitive RF, audio, and communications

applications.

Additionally,

the

MIC2202

can

be

synchronized to an external clock, or multiple MIC2202s

can easily be daisy-chained with the SYNCLOCK feature.

The MIC2202 has a high bandwidth loop (up to 500kHz)

which allows ultra fast transient response times. This is

very useful when powering applications that require fast

dynamic response such as CPU cores and RF circuitry in

high performance cellular phones and PDAs. The

MIC2202 is available in 10-pin MSOP and 10-pin 3mm ×

3mm MLF

temperature 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: 2.3V to 5.5V

• Output down to 0.5V/600mA

• 2MHz PWM operation

• Stable with 1µF ceramic output capacitor.

• Ultra-fast transient response (up to 500kHz GBW)

• Internal compensation

• All ceramic capacitors

• >95% efficiency

• Fully integrated MOSFET switches

• Easily synchronized to external clock

• SYNCLOCK feature to daisy chain multiple 2202s

• Requires only 4 external components

• 1% line and load regulation

• Logic controlled micropower shutdown

• Thermal shutdown and current limit protection

options

• –40°C to +125°C junction temperature range

Applications

• Cellular phones

• PDAs

• 802.11 WLAN power supplies

• FPGA/ASIC power supplies

• Dynamically adjustable power supply for CDMA/W-

CDMA RF power amps

• DSL modems

• Tape drives

___________________________________________________________________________________________________________

Typical Application

10nF

2.2µH

3.3V

600mA

2.3V to 5.5V

1µF

10k

1.78k

EN

6

5

1

SYNC_IN

SYNC_OUT

10

9

8

7

2

3

4

Adjustable Output Synchronous Buck Regulator

60

65

70

75

80

85

90

95

100

0

0.1 0.2

0.3 0.4 0.5 0.6

OUTPUT CURRENT (A)

5V

IN

4.2V

IN

L = 2.2µH

C