TPIC8101: The SPI OUT pin cannot output a signal

Hi Vayne,

Thank you for posting to the Sensors forum!

Is the behavior that you are noticing occurring with multiple devices, or just this one?

Regarding the SPI OUT pin (SDO) of the device, are there any other components attached to this pin (capacitors, resistors, etc.)? 

Best,

~Alicia

Hi Alicia,

Thank you for your reply,

Their design is currently connected to a power chip, and the communication of the power chip is normal

Hi Vayne,

I will need to test this out on my end. However, I will be out for Thanksgiving and will not be able to provide you with an update until then.

Best,

~Alicia

Hi Alicia,

May I ask if you have tested it on your device?We look forward to your reply.

Thank you~

Hi Vayne,

What is the status of the INT/HOLD pin as you try to communicate to the TPIC8101 device? Are you holding it low the entire time?

Best,

~Alicia

Hi Alicia,

Yes,

INT has always been in a low state,

The SOUT pin can send data, but when CS is connected to 8101, it is pulled high and becomes FF. If disconnected, normal data will be restored

Hi Vayne,

Is this something that is happening on multiple devices, or just the one? Also, are you trying to use the default SPI mode or advanced SPI mode.

Best,

~Alicia

Hi Alicia,

Now all devices are experiencing this phenomenon, using the advance mode.

Hi Vayne,

1. To enter advanced SPI mode, 0x71 should be sent over SDI, similar to the waveform below.
2. Next, write 010xxxx0 into the SDI terminal to setup the device to transmit D(7:0) of the digital integrator output. The xxxx should be the OSCin frequency per Table 3. The data will transfer out of the SDO terminal on the next transfer.
3. Write 1110000x into the SDI terminal to setup the device to transmit D(9:8) of the digital integrator output. The "x" is the channel being selected per Table 3. Read D(7:0) of the digital integrator output on the SDO terminal as data is written into the device. 

4. Write 1110000x into the SDI terminal to setup the device to transmit D(9:8) of the digital integrator output, if you do not want to read a different output selection. The "x" is the channel being selected per Table 3. Read D(7:0) of the digital integrator output on 

Let me know if this helps!

Best,

~Alicia