Digitally Programmable
Dual Full-Bridge MOSFET Driver
A3985
Pin-out Diagram
C2A
GH2A
S2A
1
2
38 C2B
37 GH2B
Bridge 2
3
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
20
S2B
Control
GL2A
NC
4
GL2B
NC
5
6
VREG
VBB
LSS2
7
SENSE2
WC
8
GL1A
S1A
9
SDO
SDI
Serial
Interface
10
11
12
13
GH1A
C1A
STR
SCK
NC
C1B
GH1B
Bridge 1
Control
S1B 14
GL1B 15
VDD
NC
LSS1 16
OSC
NC
SENSE1 17
NC 18
REF
GND
ENABLE 19
Terminal List Table
Number
Name
C2A
GH2A
S2A
GL2A
NC
Description
1
2
3
4
Phase 2 bootstrap capacitor drive A connection
Phase 2 high-side gate drive A
Phase 2 motor connection A
Phase 2 low-side gate drive A
No internal connection
5
6
7
VREG
VBB
Regulator decoupling capacitor connection
Motor supply voltage
8
9
GL1A
S1A
GH1A
C1A
C1B
GH1B
S1B
GL1B
LSS1
SENSE1
NC
ENABLE
GND
REF
NC
OSC
NC
VDD
NC
SCK
STR
SDI
SDO
WC
SENSE2
LSS2
NC
GL2B
S2B
Phase 1 low-side gate drive A
Phase 1 motor connection A
Phase 1 high-side gate drive A
Phase 1 bootstrap capacitor drive A connection
Phase 1 bootstrap capacitor drive B connection
Phase 1 high-side gate drive B
Phase 1 motor connection B
Phase 1 low-side gate drive B
Phase 1 low-side source connection
Phase 1 bridge current sense input
No internal connection
Output enable
Ground
Reference voltage
No internal connection
External clock input, ROSC resistor connection
No internal connection
Logic supply voltage
No internal connection
Serial Data Clock
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
Serial Data Strobe
Serial Data Input
Serial Data Output
Write Configuration Enable
Phase 2 bridge current sense input
Phase 2 low-side source connection
No internal connection
Phase 2 low-side gate drive B
Phase 2 motor connection B
Phase 2 high-side gate drive B
Phase 2 bootstrap capacitor drive B connection
GH2B
C2B
Allegro MicroSystems, Inc.
115 Northeast Cutoff, Box 15036
14
Worcester, Massachusetts 01615-0036 (508) 853-5000
www.allegromicro.com
ALLEGRO [ ALLEGRO MICROSYSTEMS ]
