Part Number:DRV8308
We have a custom board with DRV8308. We're running at 24V. We're trying to run at constant 5500 rpm.
We observed that when we increase the load on the motor, the controller can not keep the speed locked, the motor slows down. When we look at in detail, we suspected that the OCP was kicking in. So, we modified our OCP resistor from 100mohms to 50mohms. However, with this configuration, the motor doesn't even start spinning properly. It keeps stuttering.
We then went further ahead and removed the OCP resistor and placed a 0ohm resistor. Again, in this configuration, the motor doesn't start spinning, it stutters continously.
When we replace the resistor back with a 100mohm resistor, the motor start spinning properly (under light loads). As we increase the load though, the speed decreases from target speed.
We're at a loss as to why shorting the OCP resistor is causing a problem. Any ideas?
BTW, here is our register map:
0, 0x61, 0x41,
1, 0, 33,
2, 3, 180,
3, 0x6f, 0x82,
4, 0x0, 0x4b,
5, 0, 9,
6, 0x84, 0xb1,
7, 0x03, 0xba,
8, 0x01, 0x2c,
9, 0x02, 0x50,
10, 0xf0, 225,
11, 0x0f, 0xa0
