April 2004

1

M9999-042704

MIC2193

Micrel

MIC2193

400kHz SO-8 Synchronous Buck Control IC

General Description

Micrel’s MIC2193 is a high efficiency, PWM synchronous

buck control IC housed in the SO-8 package. Its 2.9V to 14V

input voltage range allows it to efficiently step down voltages

in 3.3V, 5V, and 12V systems as well as 1- or 2-cell Li Ion

battery powered applications.

The MIC2193 solution saves valuable board space. The

device is housed in the space-saving SO-8 package, whose

low pin-count minimizes external components. Its 400kHz

PWM operation allows a small inductor and small output

capacitors to be used. The MIC2193 can implement all-

ceramic capacitor solutions.

The MIC2193 drives a high-side P-channel MOSFET, elimi-

nating the need for high-side boot-strap circuitry. This feature

allows the MIC2193 to achieve maximum duty cycles of

100%, which can be useful in low headroom applications. A

low output driver impedance of 4

Ω allows the MIC2193 to

drive large external MOSFETs to generate a wide range of

output currents.

The MIC2193 is available in an 8 pin SOIC package with a

junction temperature range of –40

°C to +125°C.

Typical Application

3.3V

0.012

Ω

Si9803

(

×2)

3.8

µH

2k

120

µF

6.3V

(

×2)

2.2nF

MIC2193BM

VIN

VDD

CS

OUTP

GND

COMP OUTN

FB

1.8V, 5A

Si9804

(

×2)

22.6k

10k

220

µF

6.3V

(

×2)

1

µF

Adjustable Output Synchronous Buck Converter

Features

• 2.9V to 14V input voltage range

• 400kHz oscillator frequency

• PWM current mode control

• 100% maximum duty cycle

• Front edge blanking

• 4

Ω output drivers

• Cycle-by-cycle current limiting

• Frequency foldback short circuit protection

• 8 lead SOIC package

Applications

• Point of load power supplies

• Distributed power systems

• Wireless Modems

• ADSL line cards

• Servers

• Step down conversion in 3.3V, 5V, and 12V systems

• 1-and 2-cell Li Ion battery operated equipment

Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com