MIC5021_05 Datasheet, PDF (1/10 Pages) Micrel Semiconductor – High-Speed High-Side MOSFET Driver

MIC5021
MIC5021
Micrel, Inc.
High-Speed High-Side MOSFET Driver
General Description
The MIC5021 high-side MOSFET driver is designed to oper-
ate at frequencies up to 100kHz (5kHz PWM for 2% to 100%
duty cycle) and is an ideal choice for high speed applications
such as motor control, SMPS (switch mode power supplies),
and applications using IGBTs. The MIC5021 can also operate
as a circuit breaker with or without automatic retry.
A rising or falling edge on the input results in a current source
pulse or sink pulse on the gate output. This output current
pulse can turn on a 2000pF MOSFET in approximately 550ns.
The MIC5021 then supplies a limited current (< 2mA), if
necessary, to maintain the output state.
An overcurrent comparator with a trip voltage of 50mV makes
the MIC5021 ideal for use with a current sensing MOSFET. An
external low value resistor may be used instead of a sensing
MOSFET for more precise overcurrent control. An optional
external capacitor placed from the C_T pin to ground may be
used to control the current shutdown duty cycle (dead time)
from 20% to < 1%. A duty cycle from 20% to about 75% is
possible with an optional pull-up resistor from C_T to V_DD.
The MIC5021 is available in 8-pin SOIC and plastic DIP
packages.
Other members of the MIC502x family include the MIC5020
low-side driver and the MIC5022 half-bridge driver with a
cross-conduction interlock.
Features
• 12V to 36V operation
• 550ns rise/fall time driving 2000pF
• TTL compatible input with internal pull-down resistor
• Overcurrent limit
• Gate to source protection
• Internal charge pump
• 100kHz operation guaranteed over full temperature and
operating voltage range
• Compatible with current sensing MOSFETs
• Current source drive reduces EMI
Applications
• Lamp control
• Heater control
• Motor control
• Solenoid switching
• Switch-mode power supplies
• Circuit breaker
Ordering Information
Part Number
Standard Pb-Free
Temperature
Range
Package
MIC5021BM MIC5021YM –40ºC to +85ºC 8-pin SOIC
MIC5021BN MIC5021YN –40ºC to +85ºC 8-pin Plastic DIP
Typical Application
10µF
TTL Input
optional*
+12V to +36V
MIC5021
1
8
V _DD V _BOOST
2
Input
7
Gate
3
C_T
4
Gnd
6
Sense-
5
Sense+
N-Channel
Power MOSFET
2.7
nF
R_{S E N S E}
Load
R_{S E N S E}
=
50mV
I_{T R I P}
* increases time before retry
High-Side Driver with Overcurrent Trip and Retry
Micrel, Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 [phone] • fax + 1 [phone] • http://www.micrel.com
July 2005
1
MIC5021