MIC5022_05 Datasheet, PDF (2/10 Pages) Micrel Semiconductor – Half-Bridge MOSFET Driver

MIC5022
Pin Configuration
1 V_DD
2 Input
V_{B OOS T} 14
Gate H 13
3 Fault Sense H– 12
4 C_TH Sense H+ 11
5 Enable Gate L 10
6 C_TL
7 Gnd
Sense L– 9
Sense L+ 8
1 V_DD
2 NC
3 Input
NC 16
V_BOOST 15
Gate H 14
4 Fault Sense H– 13
5 C_TH Sense H+ 12
6 Enable Gate L 11
7 C_TL Sense L– 10
8 Gnd Sense L+ 9
Micrel, Inc.
Pin Description
DIP Pin No. SOIC Pin No.
1
1
2
3
3
4
4
5
5
6
6
7
7
8
8
8
9
10
10
11
11
12
12
13
13
14
14
15
DIP Package
(N)
SOIC Package
(WM)
Pin Name
V_DD
Input
Fault
C_TH
Enable
C_TL
Gnd
Sense L +
Sense L –
Gate L
Sense H +
Source H –
Gate H
V_BOOST
Pin Function
Supply: +12V to +36V. Decouple with ≥ 10µF capacitor.
TTL Compatible Input: Logic high turns the high-side external MOSFET
on and the low-side external MOSFET off. Logic low turns the high-side
external MOSFET off and the low-side external MOSFET on. An internal
pull-down returns an open pin to logic low.
When either sense voltage exceeds threshold, open collector output is open
circuit for 5µs (t_G(ON)), then pulled low for t_G(OFF). t_G(OFF) is adjustable from
C_T.
Retry Trimming Capacitor, High Side: Controls the off time (t_G(OFF)) of the
overcurrent retry cycle. (Duty cycle adjustment.)
• Open = approx. 20% duty cycle.
• Capacitor to Ground = approx. 20% to < 1% duty cycle.
• Pullup resistor = approx. 20% to approx. 75% duty cycle.
• Ground = maintained shutdown upon overcurrent condition.
Output Enable: Disables operation of the output drivers; active high. An
internal pull-down returns an open pin to logic low.
Retry Trimming Capacitor, Low Side: Same function as C_TH.
Circuit Ground
Current Sense Comparator (+) Input, Low Side: Connect to source of low-
side MOSFET. A built-in offset (nominal 50mV) in conjunction with R_SENSE
sets the load overcurrent trip point.
Current Sense Comparator (–) Input, Low Side: Connect to the negative
side of the low-side sense resistor.
Gate Drive, Low Side: Drives the gate of an external power MOSFET. Also
limits V_GS to 15V max. to prevent Gate to Source damage. Will sink and
source current.
Current Sense Comparator (+) Input, High Side: Connect to source of high-
side MOSFET. A built-in offset (nominal 50mV) in conjunction with R_SENSE
sets the load overcurrent trip point.
Current Sense Comparator (–) Input, High Side: Connect to the negative
side of the high-side sense resistor.
Gate Drive, High Side: Drives the gate of an external power MOSFET. Also
limits V_GS to 15V max. to prevent Gate to Source damage. Will sink and
source current.
Charge Pump Boost Capacitor: A bootstrap capacitor from V_BOOST to
the MOSFET source pin supplies charge to quickly enhance the external
MOSFET’s gate .
MIC5022
2
July 2005