
MIC4420/4429
General Description
MIC4420, MIC4429 and MIC429 MOSFET drivers are
tough, ef?cient, and easy to use. The MIC4429 and MIC429
are inverting drivers, while the MIC4420 is a non-inverting
driver.
They are capable of 6A (peak) output and can drive the larg-
est MOSFETs with an improved safe operating margin. The
MIC4420/4429/429 accepts any logic input from 2.4V to V S
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.
MIC4420/4429/429 drivers can replace three or more
discrete components, reducing PCB area requirements,
simplifying product design, and reducing assembly cost.
Modern BiCMOS/DMOS construction guarantees freedom
from latch-up. The rail-to-rail swing capability insures ad-
equate gate voltage to the MOSFET during power up/down
sequencing.
Micrel, Inc.
MIC4420/4429
6A-Peak Low-Side MOSFET Driver
Bipolar/CMOS/DMOS Process
Features
? CMOS Construction
? Latch-Up Protected: Will Withstand >500mA
Reverse Output Current
? Logic Input Withstands Negative Swing of Up to 5V
? Matched Rise and Fall Times ................................ 25ns
? High Peak Output Current ............................... 6A Peak
? Wide Operating Range ............................... 4.5V to 18V
? High Capacitive Load Drive ............................10,000pF
? Low Delay Time .............................................. 55ns Typ
? Logic High Input for Any Voltage From 2.4V to V S
? Low Equivalent Input Capacitance (typ) ..................6pF
? Low Supply Current ...............450μA With Logic 1 Input
? Low Output Impedance ......................................... 2.5Ω
? Output Voltage Swing Within 25mV of Ground or V S
Applications
? Switch Mode Power Supplies
? Motor Controls
? Pulse Transformer Driver
? Class-D Switching Ampli?ers
Note: See MIC4120/4129 for high power and narrow
pulse applications.
Functional Diagram
V S
IN
0.1mA
2k?
0.4mA
MIC4429
IN V E R T I N G
OUT
MIC4420
NONINVERTING
GND
Micrel, Inc. ? 2180 Fortune Drive ? San Jose, CA 95131 ? USA ? tel + 1 (408) 944-0800 ? fax + 1 (408) 474-1000 ? http://www.micrel.com
July 2005
1
M9999-072205