DRV8711 Datasheet, PDF (10/34 Pages) Texas Instruments – STEPPER MOTOR CONTROLLER IC

DRV8711
SLVSC40 – JUNE 2013
FUNCTIONAL DESCRIPTION
www.ti.com
PWM Motor Drivers
The DRV8711 contains two H-bridge motor pre-drivers with current-control PWM circuitry.
More detailed descriptions of the sub-blocks are described in the following sections.
Direct PWM Input Mode
Direct PWM mode is selected by setting the PWMMODE bit in the OFF register. In direct PWM input mode, the
AIN1, AIN2, BIN1, and BIN2 directly control the state of the output drivers. This allows for driving up to two
brushed DC motors. The logic is shown below:
Table 1. Direct PWM Input Mode Logic
xIN1
0
0
1
1
xIN2
0
1
0
1
xOUT1
Z
L
H
L
xOUT2
Z
H
L
L
OPERATION
Asynchronous Fast Decay
Reverse Drive
Forward Drive
Slow Decay
Note that if mixed or auto mixed decay modes are used, they will apply to every cycle, since current change
information is not available.
In direct PWM mode, the current control circuitry is still active. The full-scale VREF is set to 2.75 V. The
TORQUE register may be used to scale this value, and the ISEN sense amp gain may still be set using the
ISGAIN bits of the CTRL register.
xIN1
xIN2
PWM
logic
Gate
Drive
&
OCP
Gate
Drive
&
OCP
VM
x1HS
xOUT1
x1LS
VM
x2HS
xOUT2
x2LS
Comp
Comp
ISEN
amp
xISENP
xISENN
R_ISENSE
VREF
X
1V
TORQUE
Torque
DAC
ISGAIN
Figure 1. Direct PWM Input Mode
10
Submit Documentation Feedback
Product Folder Links: DRV8711
Copyright © 2013, Texas Instruments Incorporated