GekkoScience BM1384 Project Development Discussion - page 96.

notlist3d

legendary

Activity: 1456

Merit: 1000

Quote from: sidehack on March 28, 2015, 05:23:36 PM

This is for the one-chip stick miner. Even given that the VRM will probably be at best 90% efficient, it'll probably be possible to get <0.4W/GH board-level at reasonable clock speeds. The stock setting I'm shooting for getting 8GH at 2.5W which is about 0.3W/GH board-level. I won't actually know how well the buck circuit performs until I've had a chance to assemble and test it, which will wait on parts so end of next week. And I won't know board-level expected W/GH until the week after when I have the BM1384 breakout board in hand and testing.

I'm verifying the PCB layout now. It's a lame-O 2-layer so not terribly dense but Novak'll be toner-transfer etching it and we're not quite magicians yet. Hopefully it works as expected when we get to testing it.

I would love to see you squeeze that number in efficiency, would be a accomplishment.

Still enjoying keeping up in thread. Can see lots of work going on. Very fun to look at as most seem so secretive on development.

jekecoin

sr. member

Activity: 427

Merit: 250

Quote from: sidehack on March 29, 2015, 06:30:11 PM

First look at the Compac PCB layout. I'm probably gonna have to adjust a few things because I just realized I forgot to wrangle the logic level shifter outputs, but other than that it's the entire adjustable VCore regulator circuit, both LDOs for BM1384's logic and PLL voltages, the oscillator, USB communication and some status LEDs in one square inch. Holy balls I hope it works. The top half will be much simpler, and almost entirely under a heatsink.

Wow, that's great sire, I need it on my hand.

sidehack

legendary

Activity: 3374

Merit: 1859

Curmudgeonly hardware guy

Also, Novak doesn't really trust the stability of a single-chip-wide string so I think we're gonna put a per-node overvolt checker on the Amita that will keep track of each chip's Vcore and if it goes over a safety threshold (0.8-0.85V probably) will kick off the regulator and kill power to the circuit. There should be enough capacitance to buffer out momentary jitters but that should prevent it from going Full Prisma™ and blowing up. If it works well enough I'll probably figure out how to stick it on the TypeZero boards. It adds complexity to the system, which we're generally not in favor of, but adding modular complexity in a way that increases overall reliability (instead of decreasing it, as complexity tends to do) is not a bad thing.

[EDIT]

First look at the Compac PCB layout. I'm probably gonna have to adjust a few things because I just realized I forgot to wrangle the logic level shifter outputs, but other than that it's the entire adjustable VCore regulator circuit, both LDOs for BM1384's logic and PLL voltages, the oscillator, USB communication and some status LEDs in one square inch. Holy balls I hope it works. The top half will be much simpler, and almost entirely under a heatsink.

HerbPean

legendary

Activity: 1638

Merit: 1005

Quote from: sidehack on March 29, 2015, 02:48:54 PM

Pshaw. Novak's the king of not sleeping. He has some pretty great stories of consecutive all-nighters and such. Every time I come in and say "yeah I was up until 2AM" he just kinda shrugs and says "I was up until 5".

Hahahahha

Great project, thanks for sharing !

ManeBjorn

legendary

Activity: 1288

Merit: 1004

I am looking forward to these. I want to review them as well for you.
Keep up the good work and I am glad it has been fun. Grin

Quote from: sidehack on March 29, 2015, 02:25:08 AM

Okay, 13 hours is enough for one day for PCB design. Regulator test board is done and Novak might be etching tomorrow, so that's cool. And I've got almost one square inch of the stickminer laid out, which means the entire comms and Vcore regulator. Still got a couple LDOs to tuck in the corner but there's plenty of room, and then the actual ASIC and its associated parts. I probably won't get back to it until Monday night or Tuesday, but I should have enough info to spec a heatsink after a couple more hours of work.

This is probably the most enjoyable project I've ever worked on. We gotta have a giant cheeseburger party or something when we get working stickminers done. It's very exciting.

valkir

legendary

Activity: 1484

Merit: 1004

ahaha you guys are not human! You are a machine! Grin

sidehack

legendary

Activity: 3374

Merit: 1859

Curmudgeonly hardware guy

Pshaw. Novak's the king of not sleeping. He has some pretty great stories of consecutive all-nighters and such. Every time I come in and say "yeah I was up until 2AM" he just kinda shrugs and says "I was up until 5".

daddyfatsax

hero member

Activity: 857

Merit: 1000

Anger is a gift.

Sleep?? Who needs sleep? Apparently you don't. Posting at 2:40 am and then barely 8 hours later. I can't really convey a fake scolding tone over the internet, but just pretend.

sidehack

legendary

Activity: 3374

Merit: 1859

Curmudgeonly hardware guy

I actually need to spend a couple days on other things. Unfortunately I've been shirking my duties in order to put in those long hours because it's actually really fun. But my house is a mess and I have hosting customers waiting on router configs and... um... gotta sleep sometime? I'm most satisfied at work when I have a lot of different things going on, so the past few weeks I've been swimmin' in it. A lot of the last year has been spent toying with projects we wouldn't have the money to build, or waiting on customers to get off their butts and TCB, or boring but essential manufacturing tasks. I'm really glad to have a complex and entertaining project, and it's even more satisfying to see other people getting behind it.

valkir

legendary

Activity: 1484

Merit: 1004

Quote from: sidehack on March 29, 2015, 02:25:08 AM

Okay, 13 hours is enough for one day for PCB design...

Nice work man! Keep it up and a cheeseburger party for sure! Grin

Finksy

legendary

Activity: 1022

Merit: 1003

Nice work sidehack, going to be interesting to see the results.

Unacceptable

legendary

Activity: 2212

Merit: 1001

Quote from: sidehack on March 29, 2015, 02:42:40 AM

I'm sorry, sir - but that comment was...

*puts on sunglasses*

...Unacceptable.

(nothing really meant by it, I've just been wanting to say that for a while because it's funny)

Exactly what I was looking for!! Cheesy

I'm not thin skinned,like some folks,in fact if I don't get a "Fuck You" daily from them,they're NOT my friends!! Grin

sidehack

legendary

Activity: 3374

Merit: 1859

Curmudgeonly hardware guy

I'm sorry, sir - but that comment was...

*puts on sunglasses*

...Unacceptable.

(nothing really meant by it, I've just been wanting to say that for a while because it's funny)

Unacceptable

legendary

Activity: 2212

Merit: 1001

Quote from: sidehack on March 29, 2015, 02:25:08 AM

Okay, 13 hours is enough for one day for PCB design. Regulator test board is done and Novak might be etching tomorrow, so that's cool. And I've got almost one square inch of the stickminer laid out, which means the entire comms and Vcore regulator. Still got a couple LDOs to tuck in the corner but there's plenty of room, and then the actual ASIC and its associated parts. I probably won't get back to it until Monday night or Tuesday, but I should have enough info to spec a heatsink after a couple more hours of work.

This is probably the most enjoyable project I've ever worked on. We gotta have a giant cheeseburger party or something when we get working stickminers done. It's very exciting.

Curmudgeon on!!!!!!!!!! Grin

sidehack

legendary

Activity: 3374

Merit: 1859

Curmudgeonly hardware guy

Okay, 13 hours is enough for one day for PCB design. Regulator test board is done and Novak might be etching tomorrow, so that's cool. And I've got almost one square inch of the stickminer laid out, which means the entire comms and Vcore regulator. Still got a couple LDOs to tuck in the corner but there's plenty of room, and then the actual ASIC and its associated parts. I probably won't get back to it until Monday night or Tuesday, but I should have enough info to spec a heatsink after a couple more hours of work.

This is probably the most enjoyable project I've ever worked on. We gotta have a giant cheeseburger party or something when we get working stickminers done. It's very exciting.

sidehack

legendary

Activity: 3374

Merit: 1859

Curmudgeonly hardware guy

This is for the one-chip stick miner. Even given that the VRM will probably be at best 90% efficient, it'll probably be possible to get <0.4W/GH board-level at reasonable clock speeds. The stock setting I'm shooting for getting 8GH at 2.5W which is about 0.3W/GH board-level. I won't actually know how well the buck circuit performs until I've had a chance to assemble and test it, which will wait on parts so end of next week. And I won't know board-level expected W/GH until the week after when I have the BM1384 breakout board in hand and testing.

I'm verifying the PCB layout now. It's a lame-O 2-layer so not terribly dense but Novak'll be toner-transfer etching it and we're not quite magicians yet. Hopefully it works as expected when we get to testing it.

philipma1957

legendary

Activity: 4256

Merit: 8551

'The right to privacy matters'

Quote from: sidehack on March 28, 2015, 02:17:27 PM

Thanks. I think I'm gonna toy with the regulator test PCB design today and see what pops out.

Let us know if you can get under .4 watts per gh with it. thanks again.

sidehack

legendary

Activity: 3374

Merit: 1859

Curmudgeonly hardware guy

Thanks. I think I'm gonna toy with the regulator test PCB design today and see what pops out.

vapourminer

legendary

Activity: 4354

Merit: 3614

what is this "brake pedal" you speak of?

great thread and project.

nice to see things done the right way.

sent ya a berger tip.

philipma1957

legendary

Activity: 4256

Merit: 8551

'The right to privacy matters'

Quote from: sidehack on March 28, 2015, 10:40:36 AM

So far we've done all our assembly in-house, including the surface-mount parts. That is to say, I am our pick-and-place machine. We're saving up for a real one and hopefully we'll have it ready to roll by the time we get to assembling stickminers, but the parts count for the stickminer probably won't be more than our DPS2K board which means if I had nothing else to do I could probably still get most of them assembled in about a week. I really hope we have a pick-and-place.

Something we've talked about doing in the code (at least for the TypeZero) is an "auto-tune" feature where you set the voltage and an initial clock speed and it'll adjust the clock up or down until it's hit a stability threshold. I believe Avalon4.1 has a setting like that, and I've seen some for a Gridseed. It's up to Novak whether that gets implemented at all, and if it's set for the stickminer. I don't believe we'll be able to measure temperature on the Compac so throttling based on that isn't really a stock-circuit option.

Good work man keep it up. I will want both styles of sticks and a few boards.
Let me know what I can do to help via pm.

Topic: GekkoScience BM1384 Project Development Discussion - page 96. (Read 146665 times)