Data Sheet
29319.32
3971
DUAL DMOS
FULL-BRIDGE DRIVER
Designed to interface between external PWM control logic and
inductive loads such as relays, solenoids, dc motors, or stepper motors,
each full bridge can operate with output currents to ±2.5 A and operating
voltages to 50 V.
Low r
DS(on)
DMOS output drivers provide low power dissipation
during PWM operation. Internal charge pump circuitry is used to create
a boosted voltage to fully enhance the high-side DMOS switches.
Three TTL-compatible logic-input terminals per bridge allow flex-
ibility in configuring PWM control.
Internal circuit protection includes thermal shutdown with hysteresis,
and crossover-current protection. Special power -up sequencing is not
required.
The A3971SLB is supplied in a 24-lead plastic SOIC with a copper
batwing tab. The power tab is at ground potential and needs no electri-
cal isolation.
FEATURES
a73 ±2.5 A Load Current Capability per Bridge
a73 Parallel Outputs for 5 A Load-Current Capability
a73 Low r
DS(on)
Outputs
Typically 325 mΩ source, 175 mΩ sink
a73 Synchronous Rectification via Control Logic
a73 Internal Undervoltage Monitor
a73 Crossover-Current Protection
a73 Source Connections for External Current Sensing
a73 Thermal Shutdown Circuitry
ADVANCE INFORMATION
(Subject to change without notice)
May 2, 2000
ABSOLUTE MAXIMUM RATINGS
at T
A
= +25°C
Load Supply Voltage, V
BB
................ 50 V
Output Current, I
OUT
Transient (<500 ns)................... ±5 A
Logic Supply Voltage,
V
DD
............................................ 7.0 V
Sense Voltage, V
SENSE
...................... 0.5 V
Logic Input Voltage Range,
V
IN
.................. -0.3 V to V
DD
+ 0.3 V
High-Side Gate Voltage........... V
BB
+ 8 V
Package Power Dissipation,
P
D
............................................. 2.2 W
Operating Temperature Range,
T
A
............................. -20°C to +85°C
Junction Temperature, T
J
............. +150°C
Storage Temperature Range,
T
S
........................... -55°C to +150°C
Output duty cycle, ambient temperature, and
heat sinking may limit current rating. Under
any set of conditions, do not exceed the
specified current rating or a junction tempera-
ture of 150 °C.
Always order by complete part number: A3971SLB .
LOGICLOGIC
CHARGE PUMP
24
23
22
21
20
19
18
17
16
15
14
13
GROUND
GROUND
PWM2
S20
OUT2A
LOAD
SUPPLY2
SENSE2
OUT2B
S21
VCP
CP2
VDD
Dwg. PP-069-2
1
2
3
4
5
6
7
8
9
12
11
10
9
GROUND
GROUND
NO
CONNECTION
LOGIC
GROUND
S10
OUT1A
OUT1B
S11
PWM1
CP1
SENSE1
LOAD
SUPPLY1
NC
LOGIC
SUPPLY
VBB2VBB1