A4973SLBTR-T Datasheet, PDF (9/11 Pages) Allegro MicroSystems – Full-Bridge PWM Motor Driver

A4973
Full-Bridge PWM Motor Driver
ensure that the maximum ratings of the device are not exceeded.
If the internal fast current-decay control circuitry is used, then the
load current will regulate to a value given by:
I_LOAD = V_REF / (R_S × 2)
CAUTION: In fast current-decay mode, when the direction of
the motor is changed abruptly, the kinetic energy stored in the
motor and load inertia will be converted into current that charges
the V_BB supply bulk capacitance (power supply output and
decoupling capacitance). Care must be taken to ensure that the
capacitance is sufficient to absorb the energy without exceeding
the voltage rating of any devices connected to the motor supply.
See also the Brake Operation section, above.
Soldering Considerations. The lead (Pb) free (100%
matte tin) plating on lead terminations is 100% backward-
compatible for use with traditional tin-lead solders of any
composition, at any temperature of soldering that has been
traditionally used for that tin-lead solder alloy. Further, 100%
matte tin finishes solder well with tin-lead solders even at
temperatures below 232°C. This is because the matte tin dissolves
easily in the tin-lead. Additional information on soldering is
available on the Allegro Web site, www.allegromicro.com.
Figure 4 — Typical Application
+5 V
V_BB
BRAKE
REF
PHASE
ENABLE
1
V_BB
2
3
4
5
V_CC
6
LOGIC
7
V_BB
8
16
47 MF
15
14
13
12
11
10
9
MODE
Allegro MicroSystems, LLC
9
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com