ZHCSCV7 August 2014 DRV8833C
PRODUCTION DATA.
The DRV8833C is used in stepper or brushed DC motor control. The following design procedure can be used to configure the DRV8833C in a bipolar stepper motor application.
Table 5 gives design input parameters for system design.
Design Parameter | Reference | Example Value |
---|---|---|
Supply voltage | VM | 9 V |
Motor winding resistance | RL | 12 Ω/phase |
Motor winding inductance | LL | 10 mH/phase |
Motor full step angle | θstep | 1.8 °/step |
Target stepping level | nm | 2 (half-stepping) |
Target motor speed | v | 120 rpm |
Target chopping current | ICHOP | 200 mA |
Sense resistor | RISEN | 1 Ω |
The first step in configuring the DRV8833C requires the desired motor speed and stepping level. The DRV8833C can support full- and half-stepping modes using the PWM interface.
If the target motor speed is too high, the motor does not spin. Ensure that the motor can support the target speed.
For a desired motor speed (v), microstepping level (nm), and motor full step angle (θstep),
The chopping current (ICHOP) is the maximum current driven through either winding. This quantity depends on the sense resistor value (RXISEN).
ICHOP is set by a comparator which compares the voltage across RXISEN to a reference voltage. Note that ICHOP must follow Equation 4 to avoid saturating the motor.
where