November 2004

1

MIC2199

MIC2199

Micrel

MIC2199

300kHz 4mm ×

×

×

×

× 4mm Synchronous Buck Converter

General Description

The MIC2199 is a high-power 300kHz synchronous buck

DC-to-DC controller housed in a small 4mm × 4mm MLF™

12-lead package. The MIC2199 operates from a wide 4.5V to

32V input and can be programmed for output voltages from

0.8V to 6V. The wide input voltage capability makes the

MIC2199 an ideal solution for point-of-load DC-to-DC con-

version in 5V, 12V, 24V, and 28V systems.

The 300kHz switching frequency allows the use of a small

inductor and small output capacitors. The current mode PWM

control along with the external COMP pin allows for ease of

stability compensation and fast transient response across a

wide range of applications.

An all N-Channel synchronous architecture and powerful

output drivers allow up to 20A of output current capability.

For smaller external components, refer to the 500kHz

MIC2198.

The MIC2199 is available in a 12-pin 4mm × 4mm MLF™

package with a junction temperature range from –40°C to

125°C.

Features

• 4.5V to 32V input range

• 4mm × 4mm MLF™ package

• 300kHz PWM operation

• 95% efficiency

• Output voltage adjustable down to 0.8V

• 20A output current capability

• Drives all N-Channel MOSFETs

• Logic controlled micropower shutdown

• Cycle-by-cycle current limiting

• Adjustable undervoltage lockout

• Frequency foldback overcurrent protection

Applications

• Point-of-load DC-to-DC conversion from 5V, 12V,

24V, 28V supplies

• Telecom equipment

• Wireless modems

• Servers

• Base stations

Micrel, Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com

MLF and

Typical Application

IRF7821

IRF7821

2mH

0.01W

3.3V/7A

10kW

6.04kW

1nF

4.5V to 24V

VIN

EN/UVLO

COMP

CSH

LSD

VSW

VDD

BST

HSD

GND

VOUT

FB

2.2nF

2kW

U1 MIC2199BML

SD103BWS

0.1mF

22mF

4.7mF

220mF

4.5V–24V to 3.3V/7A Converter

85.0

90.0

95.0

100.0

02468

I

LOAD

(A)

V

Efficiency for

V