MIC4421A/4422A
9A Peak Low-Side MOSFET Driver
Bipolar/CMOS/DMOS Process
General Description
Features
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.
• High peak-output current: 9A Peak (typ.)
• Wide operating range: 4.5V to 18V (typ.)
• Minimum pulse width: 50ns
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
input from 2.4V to VS without external speed-up capacitors
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.
• 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.)
• Logic high input for any voltage from 2.4V to VS
• Low equivalent input capacitance: 7pF (typ.)
• Low supply current: 500µA (typ.)
MIC4421A/4422A drivers can replace three or more
discrete components, reducing PCB area requirements,
simplifying product design, and reducing assembly cost.
• Output voltage swing to within 25mV of GND or VS
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.
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
Data sheets and support documentation can be found on
Micrel’s web site at: www.micrel.com.
___________________________________________________________________________________________________________
Typical Application
Load
Voltage
MIC4422A
Si9410DY*
N-Channel
MOSFET
VS
1
8
7
6
VS
VS
IN
OUT
OUT
GND
+15V
0.1µF
1µF
0.1µF
On
Off
2
4,5
* Siliconix 30m, 7A max.
†
Load voltage limited by MOSFET drain-to-source rating
Low-Side Power Switch
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
M9999-062707
June 2007