CDCE62005: CDCE62005 EEPROM WRITE RELATED QUERY

Hi Dhiviya,

a reason why the EEPROM might not be programmed is that the EEPROM is locked from a previous writing attempt. Please check if EPLOCK (register 7 bit 26) is still 0.

regards,

Julian

Hi Julian, 

Thanks for your response. I have attached a word document which shows the registry settings during, after and before SPI programming.

Kindly look into that and please suggest us.

The problem we still face is we are forced to write SPI program every time we Power on. The Register settings are not getting loaded from the EEPROM.

Is there any other thing we miss during programming? Also how to ensure whether EEPROM write with Unlock is successful in GUI. We couldn't find any feedback except PLL to ensure EEPROM is being loaded with Programs.

We expect the EEPROM to automatically load the PLL settings once we Power on the System. 

Thanks,

Dhiviya k

.SPI Registers when read from CDCE.docx

Hi Dhiviya,

the EEPROM seems to be not locked. Good.

After writing your register settings have you send the EEPROM programming command?

This can be done either through the software or via SPI:

Unfortunately there is no feedback if the EEPROM programming is successful. A power cycle is the only option to see if the write was successful.

Have you tried with both software versions that are available? https://www.ti.com/product/CDCE62005?qgpn=cdce62005#design-development##software-development

Is this happening on a single device?

regards,

Julian

Hi Julian,

We tried EEPROM write via both SPI and software. It is not working. We have two boards. In both devices, we are facing the same problem again.

Both software versions are same it seems. We got only the same file when we download the other version too. Even though, we tried uninstalling the previous version and again installed with new version file. we tried in one more board too. we faced the same issue. 

As per our understanding, when the Power down signal is asserted high, EEPROM should load the programs. But it is not happening properly.

Kindly help us to resolve.

Thanks,

Dhiviya k

Hi Dhiviya,

your understanding is correct. The sequence is usually like this, that you program the desired register content via SPI. Then write the EEPROM programming word. Now, the EEPROM should be programmed and the device starts up every time with the same register settings.

From the word file that you added it seems like that you have programmed the device once with all zeros. The default startup is usually different.

I'll check with my team if they have some other ideas.

regards,

Julian

Hi Julian,

We didn't programmed EEPROM with zeros. At power on state itself, the register settings what we read are those zero register settings only. we didn't understand why the written registers change when read from EEPROM. This means either EEPROM is not written or written with errors. The register setting we are using are proven settings which are working in old boards. so it could not be the issue. 

Thanks,

Dhiviya 

Hi Dhiviya,

let me rephrase my earlier statement. If you read back all zero's then the default EEPROM setting is somehow overwritten/corrupted.

Did the EEPROM programming worked on the previous boards? If yes, what changed on the new boards? 

You said before that 2 units are affected. Have you tried ordering new ICs and replace the failing units?

regards,

Julian

Hi Julian,

Unfortunately, replacing ICs not an option. only way is to make On board ICs to work properly. Is there any other way you can suggest us to program IC other than CDCE GUI. Our another option is to try with SPI programmers.

Either way, our goal is to set CDCE EEPROM with proper register settings.

In CDCE GUI tool, Once we write all SPI registers and calibrate them, PLL lock is done and now when we read registers, proper registers settings are read back. Then when we write EEPROM and during next power cycle, PLL lock is not happening. Now when we read registers, those zeros are captured. Now again when we write registers, PLL Lock is done. So we did not code with zeros. Also EEPROM is not locked since the read back 7th register shows Unlocked state. Is there any other way to fix it.

Thanks,

Dhiviya k

Hi Dhiviya,

I have answered your co-worker in a separate thread about how to use direct SPI commands.

Does that work?

regards,

Julian