MIC4421A/4422A

9A Peak Low-Side MOSFET Driver

Bipolar/CMOS/DMOS Process

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

June 2007

M9999-062707

General Description

MIC4421A and MIC4422A MOSFET drivers are rugged,

efficient, and easy to use. The MIC4421A is an inverting

driver, while the MIC4422A is a non-inverting driver.

Both versions are capable of 9A (peak) output and can

drive the largest MOSFETs with an improved safe

operating margin. The MIC4421A/4422A accepts any logic

or resistor networks. Proprietary circuits allow the input to

swing negative by as much as 5V without damaging the

part. Additional circuits protect against damage from

electrostatic discharge.

MIC4421A/4422A drivers can replace three or more

discrete components, reducing PCB area requirements,

simplifying product design, and reducing assembly cost.

Modern Bipolar/CMOS/DMOS construction guarantees

freedom from latch-up. The rail-to-rail swing capability of

CMOS/DMOS insures adequate gate voltage to the

MOSFET during power up/down sequencing. Since these

devices are fabricated on a self-aligned process, they have

very low crossover current, run cool, use little power, and

are easy to drive.

Data sheets and support documentation can be found on

Micrel’s web site at: www.micrel.com.

Features

• High peak-output current: 9A Peak (typ.)

• Wide operating range: 4.5V to 18V (typ.)

• Minimum pulse width: 50ns

• Latch-up proof: fully isolated process is inherently

immune to any latch-up

• Input will withstand negative swing of up to 5V

• High capacitive load drive: 47,000pF

• Low delay time: 15ns (typ.)

• Low equivalent input capacitance: 7pF (typ.)

• Low supply current: 500µA (typ.)

Applications

• Switch mode power supplies

• Motor controls

• Pulse transformer driver

• Class-D switching amplifiers

• Line drivers

• Driving MOSFET or IGBT parallel chip modules

• Local power ON/OFF switch

• Pulse generators

___________________________________________________________________________________________________________

Typical Application

On

Off

VS

OUT

OUT

MIC4422A

1µF

Si9410DY*

N-Channel

MOSFET

Load

Voltage

6

17

0.1µF

VS

GND

IN

8

2

4,5

+15V

0.1µF

* Siliconix 30m, 7A max.

Low-Side Power Switch