Today we have our PCB’s back from the assembly house. These boards will each contain one ASIC chip and be individually connected to the main controller board. The Chip in the picture below is an FPGA which we are using to emulate the full functionality of the boards.
The entire space you can see in the middle of the DC/DC modules (GE Critical Power DC/DC CONVERTER 0.45-2V 40A SMD) will be consumed by our ASIC.
We would also like to share some facts about our boards with you.
The DC/DC modules we have on our boards are the largest and best quality available from GE Critical Power. Each capable of 40 amps making the max available 320 amps per ASIC
Our PCB laminat is not standard either. It has been given extra thick copper layers and multiple power and ground plains which enable it to more than handle our requirements.
We will be using these boards to fully validate the entire setup. They will consume the same power, make the same noise level, produce the same heat and run the same RTL code. The only difference will be related to hashing.
We would also like to take this opportunity to explain our design philosophy.
Our entire design strategy is based on time to market, We have as you can see over specified the PCB by quite some way, our ASIC will only consume an absolute maximum of 250 watts and we know the PCB can cope with 320 watts. This is the level of design margins we employ.
So you can use the following to see how safe our design is.
We have used a VERY large package for our die, not because our die is large, but to make sure we can handle the power and heat requirements.
We have used more DC/DC modules than strictly necessary
We have used the most pessimistic/conservative estimates in all of our simulations. Including but not limited to Yield, Performance, Power and Heat
For example while testing each part of the chain. We have tested our onboard Linux device to make sure it can handle up to 1.2TH ( The controller board also has and expansion for additional linux devices for future upgrade/ second generation)