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Old 26th Mar 2019, 1:58 am   #164
Semir_DE
Tetrode
 
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Join Date: Jan 2019
Location: Heusenstamm, (Near Frankfurt am Main), Germany.
Posts: 59
Default Re: Hedghog standards converter

Hello everyone,

Today I received two more Cyclone II FPGA boards from Aliexpress. Unfortunately both are faulty. When connected to 5V power none of the LEDs light up and the boards can not be accessed by the USB blaster. There seems to be a series of bad quality boards being offered at Ali from different vendors. This is now the second time I've received bad boards. The first delivery I got only one of two boards worked the other was also dead. Fortunately I got my money back the next day after claiming this via the "open dispute" function in Ali, but this does not solve the non working board issue of course.

I noticed that on the bad boards the cathode pin of the power LED next to the 1117 3.3V voltage regulator is not connected to ground as it should be. This is not a soldering issue but the board simply lacks the track that is needed to connect the LED to ground - a bad copy of the board I presume.

In general the soldering is very bad one board had a glob of solder bridging several pins on one of the four headers, and the FPGA most likely has bad joints. When I power up the board the crystal generates the 50Mc clock and some of the pins on the header have a steady voltage on them. Other pins, however, seem to have a floating voltage and go to high level when I press on the FPGA chip. This indicates that there are some bad joints and the FPGA probably is missing some signals. I am not going to mess with the boards and will claim them.

I would be interested to hear what experience other members had here who had ordered some boards from Aliexpress.

What a mess... It will take another 4-6 weeks for the next batch of boards to arrive, hopefully those will be of better quality.

Semir
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