MikeyMike

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About MikeyMike

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  1. MikeyMike

    Power supply issues

    Hi Jack, I have sent you an email. I really appreciate your help. Thanks.
  2. MikeyMike

    Power supply issues

    Thanks for the link to the Pipistrello looks good. Probably a bit expensive for someone getting started. Think I'll order a Papilio Pro later on and maybe even another wing while I am at it. Not sure what I'll do with the old board.
  3. MikeyMike

    Power supply issues

    offroad that link is for the XC6SLX9 Spartan 6 used on the Papilio Pro not the XC3S500E Spartan 3 used on the Papilio One. Just checked Farnell again and neither of the parts they have available are the 100 pin QFP package. Managed to find some on Digikey for around £15 each but minimum order quantity of 90!!! Getting the chip off the board wouldn't be an issue its just getting it back on Budget isn't really an issue either just a bit annoyed at having shelled out £40 for a board that is faulty. Lesson learnt test all new hardware the minute you receive it while still under warranty. Even if your not planning on using it any time soon. Starting to think its time I ordered a Papilio Pro and see how I get on with that. Mike.
  4. MikeyMike

    Power supply issues

    There seems to be some confusion on what the maximum input voltage on that jack is. 7V, 10V or 15V. Looking at the LD1117 datasheet although the device is rated at 12W max the junction to ambient thermal resistance would only allow for around 1W before the device started to over heat. Which at 12V equates to around 142 mA. Not sure how much that "hello world" bit file would cause the FPGA to draw. Getting back to my issue I first tried powering the board with 5V directly onto the 5V supply line. Still the same problem. Next I removed all of the regulators and tested them off the board. All of them appeared to work fine under no load. Then I began fitting them back onto the board one at a time. No issues arose until the 1.2V regulator was fitted. So I removed it again. I then supplied 1.2V from my bench power supply with the current limit set to 500 mA. Soon as the power was applied the current limiter tripped in. The next step would be to replace the FPGA but those Spartan chips are around £30 on Farnell. I don't have a re-flow oven so it would have to re-soldered by hand.
  5. MikeyMike

    Power supply issues

    Hi Jack, Thanks for the reply. Originally I had the "hello world" bit file downloaded to the FPGA. Which would be lost when the power is removed. So there is nothing running when it exhibits these issues which makes me think it must be a hardware issue. I understand a lot of people power these from a USB port but technically your only bypassing the 5V regulator by doing so and I'm sure the problem lies with the 2.5V and 1.2V regulators so the issue would remain. Nice to see you opted for a switch mode supply rather than using linear regs on the Papilio Pro. I am really worried about it because it isn't working. The two regulators are definitely exhibiting fault conditions and not just drawing a lot of current. This is my first venture into FPGAs and choose the Papilio because it represented really good value for money and I love open source. The problem is I bought the Papilio along with the logic start mega wing from Seedstudio back in June and hadn't got around to playing with it until now. Since more than 60 days have elapsed I would be unable to send it back under warranty. Which means I am stuck with a development board that set me back $60+ that I cant use. I know its my fault for leaving it so long before using it but annoying all the same. Also I am in the UK so getting stuff shipped to and from takes a while. There are sellers here but it still works out much cheaper to order from overseas. As it stands I am toying with the idea of cutting my loses and either ordering a Papilio Pro since I already have the logic start mega wing which I don't want to waste. Or just ordering a Digilent or Terasic development board from Farnell or RS components here in the UK. You don't anywhere near as much bang for you buck with these commercial boards it would be a easily solution. Mike.
  6. MikeyMike

    Power supply issues

    Hi guys, Thanks for the replies. Just tried powering it again from 7V this time. Measuring the outputs of the four voltage regulators I get :- U2 (5V) reads 4.879V U6 (3V3) reads 3.284V U5 (2V5) reads 2.212V U4 (1V2) reads 0.914V The whole things still drawing more than 1A because the bench supplies current limiter is kicking in. Also the 2V5 regulator is getting far to hot to touch. To be honest I too scared to plug it into my USB port in case I damage it I know it should be current limited but I don't want to risk it since why should powering it from the USB port be any different to using a external supply. Mike.
  7. MikeyMike

    Power supply issues

    Hi everyone, I recently purchased a Papilio One 500K. I have successfully managed to install the "hello world" bit file. However not without issues. One issue seems to be very similar to andyfives post here http://forum.gadgetfactory.net/index.php?/topic/2047-question-about-power-supply/. Both the 2.5V (U5) and 1.2V (U4) regulators are getting extremely hot. After testing the outputs neither are maintaining their rated output voltages. Both the 5V (U2) and 3.3V (U6) regulators appear to be fine. If I connect an external 12V power supply the entire board is drawing much more than the suggested 800 mA. With the 1.2V regulator removed from the board the 2.5V regulators output voltage is fine.Which makes sense since the 1.2V regulator is fed from the 2.5V regulator. Also the 1.2V regulator appears to be fine when tested off the board. Does anyone have any ideas ? Could the FPGA be faulty? Thanks, Mike.