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TF1260 CPLD PROBLEM

Posted: 25 Nov 2021 21:59
by kulamario
Welcome
I already soldered a few of these 1260 cards but I must say that I have huge problems
there is something that is happening inexplicable to me
I solder two cpld to 1260 cpld bus heats up terribly card does not work
now transplanting this cpld to 1230 and everything works as it should
why is this happening?
does 1260 have any special requirements for cpld?
I can not explain that
I will add that I have over 10 pieces of such cpld
for the test I bought 4 pcs in the mouser XC95288XL-10TQG144C

I suspect that Stephen twisted these chips so that he takes out of them everything he can give and maybe even more hehehe
Chinese cpld from utsource just can't do it

Re: TF1260 CPLD PROBLEM

Posted: 26 Nov 2021 09:17
by Danoo
Yes the CPLDs on my own 1260 (@alenppc built) run quite warm 40-50 C. Still works fine at 75Mhz, will eventually get around to putting some passive heatsinks on those chips one day ;). Stephen did indicate they were being pushed to the limit in a earlier post in one of the threads.

Re: TF1260 CPLD PROBLEM

Posted: 26 Nov 2021 14:12
by markus0321
Well, I saw this post, but I didn't think it would show that every good chip would work. For me it looks like this:
I made four TF1260 boards for my own needs and managed to get three up and running. While each started, the behavior was different, as if each had its own problems. I had to change the CPLD every time. In the end, on the 4th, I didn't manage to start at all and I didn't know what could be wrong with it, because I already checked everything that came to my mind.
And after all the work I had 16 CPLDs "out of order" and I thought it was the fault of bad quality integrated circuits.
Yesterday I soldered one of them to TF1230 and it turns out that it works!
So, only TF1260 did not work properly. or they must be somehow specially paired to the TF1260.
It's a bit weird. What do you think is CPLD's fault or is there a problem with the PCB?

Re: TF1260 CPLD PROBLEM

Posted: 26 Nov 2021 14:33
by terriblefire
Nothing like this has been reported by the builders. Most likely explanation is bad soldering or bad pcb.

I presume people are checking power and ground arent shorted before they start soldering. Sometimes the preassembled caps can be bad or shorted with solder.

Re: TF1260 CPLD PROBLEM

Posted: 26 Nov 2021 18:04
by arkadiusz.makarenko
I think with outgoing chip shortage, quality of parts available might be rapidly deteriorating.

Re: TF1260 CPLD PROBLEM

Posted: 28 Nov 2021 12:08
by kulamario
I found the cause of the cpld bus boiling
NB3N3020DTG with 25pcs only 15pcs I had good ones and this was what caused the cpld to heat up horribly
unfortunately, it was hard to track as every other chip is damaged
but it worked

Re: TF1260 CPLD PROBLEM

Posted: 28 Nov 2021 12:26
by terriblefire
kulamario wrote: 28 Nov 2021 12:08 I found the cause of the cpld bus boiling
NB3N3020DTG with 25pcs only 15pcs I had good ones and this was what caused the cpld to heat up horribly
unfortunately, it was hard to track as every other chip is damaged
but it worked
I get these from RS. I wouldnt trust PLLs from ebay.

Re: TF1260 CPLD PROBLEM

Posted: 28 Nov 2021 13:18
by kulamario
Oh no
I not buy on aliexpres or ebay
Utsource and mouser

Re: TF1260 CPLD PROBLEM

Posted: 28 Nov 2021 14:36
by terriblefire
kulamario wrote: 28 Nov 2021 13:18 Oh no
I not buy on aliexpres or ebay
Utsource and mouser
UTSource is worse than ebay.

Re: TF1260 CPLD PROBLEM

Posted: 28 Nov 2021 14:52
by chucky
I bought PLLs from utsourece. I think 40% was crap