SLOSE37B June 2020 – May 2022 DRV8436
PRODUCTION DATA
The first step in configuring the device requires the desired motor speed and microstepping level. If the target application requires a constant speed, then a square wave with frequency ƒstep must be applied to the STEP pin. If the target motor speed is too high, the motor does not spin. Make sure that the motor can support the target speed.
Use Equation 1 to calculate ƒstep for a desired motor speed (v), microstepping level (nm), and motor full step angle (θstep)
The value of θstep can be found in the stepper motor data sheet, or written on the motor.
For the DRV8436, the microstepping level is set by the M0 and M1 pins and can be any of the settings listed in Table 8-2. Higher microstepping results in a smoother motor motion and less audible noise, but increases switching losses and requires a higher ƒstep to achieve the same motor speed.
M0 | M1 | STEP MODE | |
---|---|---|---|
0 | 0 | Full step (2-phase excitation) with 100% current | |
0 | 330 kΩ to GND | Full step (2-phase excitation) with 71% current | |
1 | 0 | Non-circular 1/2 step | |
Hi-Z | 0 | 1/2 step | |
0 | 1 | 1/4 step | |
1 | 1 | 1/8 step | |
Hi-Z | 1 | 1/16 step | |
0 | Hi-Z | 1/32 step | |
Hi-Z | 330 kΩ to GND | 1/64 step | |
Hi-Z | Hi-Z | 1/128 step | |
1 | Hi-Z | 1/256 step |
For example, the motor is 1.8°/step for a target of 120 rpm at 1/8 microstep mode.