TC3E7:ESR0 and PORST remain low after power up

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Baymax0-0
Level 1
Level 1
5 sign-ins First reply posted First question asked

Hi,

 We are testing the programming of the TC3E7 on our own board,and because of some bugs, we did not bring the HWCFG pins out (NC), after power-on, we found that the PORST and ESR0 ports are always kept low (external pull-up), and we can't use miniwiggler to flash code (This is a empty chip). 

We checked ESR0 and PORST with an oscilloscope and found that they were only pulled up to a certain voltage and then pulled down immediately( in 200us). And we also remove the resistors related to HWCFG on the KIT_A2G_TC397_3V3_TFT, but it still can be burned.

So we want to know what factors lead to this result.

Thank you very much!

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1 Solution
MoD
Employee
Employee
50 likes received 500 replies posted 100 solutions authored

Then check all supplies, I expect that any supplies is missing therefore, PORST is low.

 

View solution in original post

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3 Replies
MoD
Employee
Employee
50 likes received 500 replies posted 100 solutions authored

Check all voltages, they are needed that PORST goes to high. There is a pull-up on PORST on your board? 

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Baymax0-0
Level 1
Level 1
5 sign-ins First reply posted First question asked

Yes, there is a pull-up (+3V3 and 2.2K) on PORST on our board

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MoD
Employee
Employee
50 likes received 500 replies posted 100 solutions authored

Then check all supplies, I expect that any supplies is missing therefore, PORST is low.

 

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