Current Sensing: MCW 6.3.2 issue when setting Internal PGA Gain for STSPIN32G4

[PCama.1]

Hello,

I have a custom motor control board and have so far been using MCW 5.Y.4

This is my Amplifying Network using internal Op-amp gain of 4x and I just have external resistors R1, and R2. The resistors R4 and R5 are internal as you well know:

Now I am migrating to MCWB 6.3.2 and am starting configuration from Inverter Board EVLSPIN32G4-ACT as I had done before.

However, in Current Sensing, I noticed that:

1.) Channel W is connected to OPAMP2, but I believe that doesn't change anything since my board has same resistor network for all three op amps and I understand that channel V will be inferred from the two other channels

2.) Internal PGA Gain of 4 (600mV) is not an option, even though this MCU has that as an option and previous firmware allowed that as you can see form the screenshot. Is this just a bug in the system, and can I simply change it manually in the code? I designed our board based on a gain of 4 so I really need that to be the case.

3.) There are no inputs for the external network for gain offset, as I had before as you can see in one of the images above. However, since that is an analog input does that mean that it won't make a difference for the firmware as long as it is between 0 and 3.3V?

I like this MCWB a lot better. However, your earlier version seemed more explicit and clear about the Current Sensing network with a nice calculator and diagram.

Could you please let me know what to do, especially regarding points 2 and 3 above?

Thank you in advance,

Paulo

[GMA · Accepted solution]

Hello @PCama.1 ,

2) "Internal PGA Gain of 4" is not available in the original EVLSPIN32G4-ACT board because it will not respect min/max VOUT or polarization offset limits for example.
Modifying EVLSPIN32G4-ACT.json file with your parameters, Internal PGA Gain of 4 is available on MC Workbench.

3) Do you mean "Offset Network Attenuation"? It is still present in EVLSPIN32G4-ACT.json file.

[PCama.1]

It makes sense. Thank you!

[PCama.1]

By the way where would the board JSON would be?

[GMA]

Hello @PCama.1,

Custom Inverter board .json files could be located in "~/.st_workbench\hardware\board\inverter".

You can also use "STMC Board Designer" tool: clone the EVLSPIN32G4-ACT board, edit and modify parameters and save it.

[PCama.1]

Hello GMA,

I am almost there but still need your help in this final stretch:

1. I created a custom board by cloning the STSPIN32G4 board. Sorry, this was the original board I used, not EVLSPIN34G...

After creating a custom board I was able to locate the 'hardware\board\inverter' folder with the json file in it.

2. I set up current sensing internal OpAmp gain and our board shunt resistor, offset network attenuation and polarization offset, same as we had before in my original post:

3. Then I created the project with the updated board, but I am encountering issues as you can see in the pictures below. There is a warning for current sensing, a weird current readable range and another warning at main screen.

[PCama.1]

Sorry for the multiple posts, but after I cloned the board and changed the .json file directly, as you suggested, everything seems to be working fine now.

Thank you!

Paulo