DLPDLCR230NPEVM: Evaluation model flashing when plugged into 5V power supply.

Hello User,

There is a safety shutdown mechanism on the EVM that occurs if the power supply is not stable at 5V (if it dips too low). Can you confirm with a multimeter that your PROJ_ON signal coming into the system is also stable?

I recommend you look at header J2 on the EVM and probe pin 37 (PROJ_ON). Are you driving the system with a Raspberry Pi or powering the system on its own?

Regards,

Philippe Dollo

Hi Philippe,

Thank you for your reply.

I am powering the system on its own.  Unfortunately the documentation for this evaluation board is currently not up (the page you are looking for cannot be found) but I tested the power supply plugged in and it is around 5.06V.  Since I do not have the documentation for the board I am just testing random pins but so far only finding pins registering 3.3V. I can try testing with a higher voltage supply but do not want to fry the board.

User,

Thanks for your feedback. 

The user guide for the board is currently being updated with a new revision, I believe. It should be back up within the next day. In the meantime I recommend you check the Reference Design associated with the board for information (which includes board schematic): https://www.ti.com/tool/TIDA-080009 

For the power supply, I definitely recommend you don't try to test with a higher supply. That might brick the device.

In terms of pin testing, which ones are you looking at? I am particularly curious about pin 37 (PROJ_ON). Is that high? During operation it should be low, and it something drives it high you might see it shut off the system (it is negative logic).

Philippe,

I checked pin 37 (PROJ_ON) and it was low.  

A more detailed description of what is happening. After plugging in the board, PROJ_ON LED turns on then is followed by D_HOST_IRQ then D_IRQ.  After a second, the D_DONE LED turns on and the the projector flashes the DLP logo for a milliseconds then the projector and all LEDs turn off.

User,

As a follow up, can you please probe the VIN (system power) of your setup to determine whether the VIN is falling below 4.65V during bootup? If this occurs the system will enter an emergency shutdown state.

At no point does the VIN fall below 5V

User,

Thanks for reporting back. We're working on reproducing the issue on our end so that we can provide a workaround as appropriate. We will post back here when we have more information.

Best Regards,

Philippe Dollo

User,

Can you share which power supply you are using with your system (that you are encountering the issue on)?

Regards,

Philippe Dollo

Philippe,

I have tried multiple 5V power supplies, all with the same outcome.

The original power supply was a 5v 3A 15w power supply with the original outcome.  I then tried one that had a 5V 5A output with the same results.  I have even tried a USB that is capable of 3A output and again, same results.

I have already ordered a new evaluation board and will try with a new 5V 3A power supply and see what happens but my hopes are optimistic.  This will hopefully verify that this board is defective.

User,

If it is available for you to use I recommend trying the ME30A0503F01. I've been able to reproduce the issue you describe with some 3A power supplies but never with this one.

As an alternative solution we can also provide you with an alternative FW build for this EVM which boots the system with reduced LED current settings. This should help alleviate the spike in current you are seeing with your system that is causing shutdown. You would need a Raspberry Pi or SPI-capable host to write to the EEPROM flash, should you choose to go this route.

I apologize for the inconvenience. I hope this information helps you find a quick resolution to the problem.

Best Regards,

Philippe Dollo

Phillippe,

Thank you very much for the recommendation, I will order that power supply today and give it a shot.

I double checked the input current and it looks like it spikes to 5A with my 3A supply.  

I'll check back in once I verify that the new power supply works.