PGA305EVM-034: Running PGA 305 on its own

Hi Igor,

I responded to this question in the following thread but will repeat my response again.

https://e2e.ti.com/support/sensors-group/sensors/f/sensors-forum/1345426/pga305evm-034-calibration-validation-running-pga305-stand-alone/5129624#5129624

If the MCU is in reset, the DAC output is 0.  Depending on the EEPROM values the output of the DAC could be zero.  Have you verified that the EEPROM values were actually written to the PGA305 by reading the values back?  Also, if the CRC value is incorrect when powering up the device, the device can be in reset.  The diagnostics, if enabled, can hold the DAC output at 0 if any of the following:

So I would recommend restarting the GUI and checking on the status of the EEPROM settings.

Best regards,

Bob B 

Good afternoon,

I have seen this email and checked what I could (see attached files).

I enabled DAC ==> maybe it is done incorrectly, please provide additional instructions on this.

CRC seems to be fine (I could read it back after it was computed and programmed)

Voltages seem to be fine.

Please help to resolve this issue.

Regards.

Igor

Hi Igor,

Can you reconnect the GUI and take some screen shots of the EEPROM data.  Make sure you are in the Digital Interface mode, then go to the EEPROM page, and on the EEPROM READ on the right-hand side click the Select checkbox and click the READ button.  The data should look something like this:

Please attach so that I can analyze.

Best regards,

Bob B

Hello Bob,

Today I have recalibrated PGA305EVM-034.

This time CRC is showing 0x00.

Previous calibration and CRC was 0xC2 (see attached file).

Please advice if the issue is fixable.

Thank you for your help.

Regards,

Igor 

You wanted to see the content of EEPROM

Hi Igor,

Try clicking on the Select box to mark all pages and then click on the READ button to actually read the values.

Best regards,

Bob B

Hello Bob,

Please see attached.

How do I calculate and write CRC correctly 

What I am asking is:

Please tell me what do I do after the calibration coefficients were calculated.

Thank you for your help.

Regards,

Igor

Hi Igor,

I'm sorry you are having such a difficult time trying to figure out the device and how it works within the confines of the EVM GUI.  Most of the information you keep asking for is in the EVM GUI user's guide.  I've attached a copy.  The user's guide that is specific to the version 1.6 of the software became corrupt somewhere in the development process, so I'm attaching the 1.5 version.  The primary difference is the Calibration Demo tab has been removed, so that feature is unavailable.

PGA305_GUI_User_Manual_v1_5.pdf

Based on the EEPROM information provided, you have not set up and saved information that relates specifically to the register value settings when the PGA305 comes out of the reset state.  So  if you manually entered the values without saving them to EEPROM, then when the PGA305 is power cycled the data will be lost.  The section I am referring to is in the following section:

There are a number of ways to calculate and set the CRC value.  One of the methods is described in section 2.3.2.5.  I have copied the information specific to the CRC below:

In the end, this part may be just too complicated for you to use.  To fully utilize this part requires a deep understanding of how the device is designed to work, an understanding of ADCs, an understanding of the M0 microprocessor, and the patience to go through the available published materials including the datasheet and other E2E responses.

As I have other responsibilities and other customers, continued support will have to be limited.

Best regards,

Bob B 

Hello Bob,

Thank you for your response.

I read GUI manual more than once and followed the explanations.

How do you select all pages and make sure that CRC is correct and M0 will run properly on its own without GUI.

Thank you for help.

Regards,

Igor

I understand that your resources are limited.

It would be very helpful if you could provide very short message with Step-by-Step instructions and screenshots.

Regards,

Igor

Hi Igor Giterman,

We appreciate your interest in this device, however at this time we are unable to offer additional support. Please use our extensive resources – including datasheets, user’s guides, application notes, FAQs, and existing E2E posts – to guide your design and help troubleshoot any issues. We apologize for any inconvenience this may cause.

-Bryan