MA600, motor speed reading through SPI

Motor Drivers/Sensors
1

Hello,

I’m using the MA600GQ-Z sensor available on Test Board TBMA600-Q-LT-00A, connected to my board through SPI at 1.25Mhz. The angle reading is working fine, with the expected resolution, and is stable enough. In the same SPI cycle (32 clocks) also the motor speed is acquired, but it is very unstable (at 4000 rpm readings spread from 3500 to 4300). The reading (acquisition) time is 2ms. I tried also to slow down at 30ms, but the result for the rpm is the same.
There is any suggestion to obtain the needed accuracy also on motor speed?

Thanks for the attention

Ezio

2

Hello,
Welcome to the MPS Forum!
Could you clarify if you are using the MA600A or MA600?
Thanks!

3

Hi Shreya,

appreciate your welcome, thank you for the reply

the sensor I’m using is that included in Test Board TBMA600-Q-LT-00A, specification says that it is MA600GQ-Z

Ezio

4

Hi Ezio,
The MA600 is not recommended for use anymore. We suggest that you use the MA600A. Please reach out if you are still facing issues with the MA600A.
Thank you.

5

Hello Ezio,

For both MA600 and MA600A, the resolution of the speed measurement is 9.5 bits (see Table 27 on page 35 of the MA600 datasheet). Considering the speed measurement full scale, this translates to approximately 500rpm. Are the values you mentioned the min and max? If yes, they could be reasonable values. Also, would it be possible for you to calculate the standard deviation of your measurements?

Best regards,

Carmine