BkkCoins... can you tell how error-resistent your design is? Burnin claimed that the chips will be working in a row. So if one chip breaks all chips stop working. Im not seeing why it should be built this way but i would like to know how your design is working. Is it the same way? And if so can a broken asic be replaced easily or are all the chips on that pcb gone then?
And you new pricelist with the parts... do one only need this kit and an old mini-oven to build a miner out of it or is there more needed?
Every design will have to accommodate the way the ASIC was designed to work.
Best knowledge right now is that the chips are arranged as a daisy chain so that data shifted in one end passes thru chips to fill a counter register in each. This is how the Icarus was done. In this case if the shift path is damaged in one chip all chips after it will be hashing wrong values. But a chip could be damaged in a way that affects it's hashing but not it's shifting, and this wouldn't affect other chips.
There is mitigation for this which I'll consider once official docs are out. If enough pins are free on the PIC then multiple serial lines from the PIC to the chips would allow nonce assignment in units smaller than 16 chips. eg. 4 serials going to 4 chips that daisy chain as a group of 4. But this is impacted by whether or not there are two serials per chip. I'm guessing not. I think there is an enable per chip that allows stopping nonce count while shifting in new data - just a guess. The Icarus didn't do that, it just counted while shifting and ignored bad results until the LSB was shifted and correct then the count was valid.
It should be fairly easy to replace an ASIC if you keep some spares. Repair shops can pull a chip and place a new one easily, and with a bit of practice on dummy chips you could likely do it too if you were inclined to that. At least you don't have to re-ball the chip as it's QFN. See youtube videos, search "qfn chip replacement".
Board, parts, oven (preferably with temp profile controller), skill, solder paste, stencil, technical aptitude, skill, some inspection magnifier probably, tweezers (preferably vacuum), dexterity with tiny parts (0402 caps are the size of a grain of rice), soldering iron for fixes and thru-hole pins. Maybe I've forgotten something, but otherwise that's it.
Is the DC Input fused?
That's good idea I hadn't thought about yet. I'll have a look at suitable parts and include one, preferably resettable. I would think a good PSU would have this covered but better to not rely on that.
