kramble / DE0-Nano-BitCoin-Miner

DE0 Nano port of fpgaminer - this is based on https://github.com/progranism/Open-Source-FPGA-Bitcoin-Miner
90 stars 35 forks source link

Calculating power usage #1

Closed brvier closed 11 years ago

brvier commented 11 years ago

Hi,

You are warning that using a speed higher than 40Mhz could fry an unmodified de0 nano, but PowerPlay Power Analyser estimate the design will use 312mW only at 50Mhz that s arround 60mA a 5V ...

Did i miss something ? I'm asking as i'm using your interesting project to learn doing calc on fpga :)

thx in advance

kramble commented 11 years ago

Hi,

I posted a reply on bitcointalk (khertan, yes?). The thing to watch when clocking it faster is the temperature of the onboard regulators (3 small chips next to the external power header). I would not want them to get too hot to touch. Also as you commented in your post the usb can only supply around 500mA (possibly a little bit more as the voltage will droop ... you will the the blue power indicator led dim).

I think PowerPlay might be a bit optimistic about the power consumption. You can see my measurements on the bitcointalk post, eg for 40MHz I was measuring 480mA from a 3.3V external supply, which is (480*1.2) = 576mW for the fpga core, neglecting the power consumption of the rest of the board.

Good luck with your project, I quite enjoyed playing with it, though my thanks go to fpgaminer, makomk and the others who did all the hard work (I just tinkered with it to get it working on my Nano, I'm just an amateur when it comes to electronics and fpga).

Regards Mark

On 3 May 2013 16:32, Benoît HERVIER notifications@github.com wrote:

Hi,

You are warning that using a speed higher than 40Mhz could fry an unmodified de0 nano, but PowerPlay Power Analyser estimate the design will use 312mW only at 50Mhz that s arround 60mA a 5V ...

Did i miss something ? I'm asking as i'm using your interesting project to learn doing calc on fpga :)

thx in advance

— Reply to this email directly or view it on GitHubhttps://github.com/kramble/DE0-Nano-BitCoin-Miner/issues/1 .

brvier commented 11 years ago

Thanks a lot for your explanations.