bassclef
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June 17, 2013, 04:28:44 AM |
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Perhaps I could get a show of hands from those who think they would actually buy a kit or board that would require assembly docs?
Yes, this would be my preferred way to go . But I'm obviously not buying large volumes since it's gonna be done manually. Yep, me too. Have the skills to do it so i'd like to make a 16 chip Klondike and 4 little USB ones with the 20 chips I have coming soon. Have you got a plan in place for supplying kits to people? (for ordering and logistics) I'd assume there would be a fair bit of demand. Most people would probably go for a pre-made option though. This is my preferred method as well. I would love to have a kit with boards, parts, stencil and basic assembly instructions.
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wrenchmonkey
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June 17, 2013, 04:43:26 AM |
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Ideally, I'd like to get pre-assembled boards that just need chips, so that they're ready to just flow the chips in, when they arrive.
That said, I'm interested in kits if that's not an option.
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vs3
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June 17, 2013, 04:52:55 AM |
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Ideally, I'd like to get pre-assembled boards that just need chips, so that they're ready to just flow the chips in, when they arrive.
That said, I'm interested in kits if that's not an option.
I suspect it would be somewhat of a challenge to solder another chip to a board that already has a lot of other stuff soldered... (that's unless you're looking for manually soldering it, which isn't necessarily any easier but likely has a better probability of success )
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wrenchmonkey
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June 17, 2013, 05:07:52 AM |
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Ideally, I'd like to get pre-assembled boards that just need chips, so that they're ready to just flow the chips in, when they arrive.
That said, I'm interested in kits if that's not an option.
I suspect it would be somewhat of a challenge to solder another chip to a board that already has a lot of other stuff soldered... (that's unless you're looking for manually soldering it, which isn't necessarily any easier but likely has a better probability of success ) Why would it be difficult? That's literally WHY they make re-flow ovens, and why they call them "Reflow" ovens.
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vs3
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June 17, 2013, 05:23:07 AM |
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Ideally, I'd like to get pre-assembled boards that just need chips, so that they're ready to just flow the chips in, when they arrive.
That said, I'm interested in kits if that's not an option.
I suspect it would be somewhat of a challenge to solder another chip to a board that already has a lot of other stuff soldered... (that's unless you're looking for manually soldering it, which isn't necessarily any easier but likely has a better probability of success ) Why would it be difficult? That's literally WHY they make re-flow ovens, and why they call them "Reflow" ovens. Although I agree that it isn't impossible it would add way too many ifs to the equation. Not all components have the same (reflow) temperature characteristics, some require to be kept at various temperatures for short times while others may need longer times. Then if you have any through-whole components and connectors, especially some plastic materials - they may be affected by that process. So - yes, it is possible, but you really have to design the whole board for that from the very beginning. And even then you may have to wait until you add all chips and then finish the board and add some of the other components. In other words - you wont be able (at least easily) to really "finish" the board and just wait to solder the last chip.
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trigeek
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June 17, 2013, 05:54:49 AM |
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Keep your unsourced blind accusations with no evidence in your own thread. No need to spam it all over the custom hardware forum.
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wrenchmonkey
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June 17, 2013, 08:44:53 AM |
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Ideally, I'd like to get pre-assembled boards that just need chips, so that they're ready to just flow the chips in, when they arrive.
That said, I'm interested in kits if that's not an option.
I suspect it would be somewhat of a challenge to solder another chip to a board that already has a lot of other stuff soldered... (that's unless you're looking for manually soldering it, which isn't necessarily any easier but likely has a better probability of success ) Why would it be difficult? That's literally WHY they make re-flow ovens, and why they call them "Reflow" ovens. Although I agree that it isn't impossible it would add way too many ifs to the equation. Not all components have the same (reflow) temperature characteristics, some require to be kept at various temperatures for short times while others may need longer times. Then if you have any through-whole components and connectors, especially some plastic materials - they may be affected by that process. So - yes, it is possible, but you really have to design the whole board for that from the very beginning. And even then you may have to wait until you add all chips and then finish the board and add some of the other components. In other words - you wont be able (at least easily) to really "finish" the board and just wait to solder the last chip. Are you joking? How would you flow the board in the first place, if that were an issue?
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Enigma81
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June 17, 2013, 08:48:26 AM |
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Ideally, I'd like to get pre-assembled boards that just need chips, so that they're ready to just flow the chips in, when they arrive.
That said, I'm interested in kits if that's not an option.
I suspect it would be somewhat of a challenge to solder another chip to a board that already has a lot of other stuff soldered... (that's unless you're looking for manually soldering it, which isn't necessarily any easier but likely has a better probability of success ) Why would it be difficult? That's literally WHY they make re-flow ovens, and why they call them "Reflow" ovens. Although I agree that it isn't impossible it would add way too many ifs to the equation. Not all components have the same (reflow) temperature characteristics, some require to be kept at various temperatures for short times while others may need longer times. Then if you have any through-whole components and connectors, especially some plastic materials - they may be affected by that process. So - yes, it is possible, but you really have to design the whole board for that from the very beginning. And even then you may have to wait until you add all chips and then finish the board and add some of the other components. In other words - you wont be able (at least easily) to really "finish" the board and just wait to solder the last chip. Are you joking? How would you flow the board in the first place, if that were an issue? The Thru-Hole components likely would melt. That is one of the reasons why Thru-Hole assembly is (nearly) always done after surface mount. Temperatures inside a reflow oven reach as much as 260 degrees c. Thru-Hole components do not get that hot during assembly, so there is generally no reason to use plastic that can survive those types of temperatures. That being said, it's very easy to put the Avalon chips on the board by hand (using an iron or a hot-air rework gun). I could attach 16 QFN chips in less than 16 minutes. Enigma
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mrm0
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June 17, 2013, 06:30:44 PM |
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The Thru-Hole components likely would melt. That is one of the reasons why Thru-Hole assembly is (nearly) always done after surface mount. Temperatures inside a reflow oven reach as much as 260 degrees c. Thru-Hole components do not get that hot during assembly, so there is generally no reason to use plastic that can survive those types of temperatures.
That being said, it's very easy to put the Avalon chips on the board by hand (using an iron or a hot-air rework gun). I could attach 16 QFN chips in less than 16 minutes.
Enigma
With standard QFN packages I agree, it is quite easy and fast with hot-air. However, these particular chips have a large thermal pad at the bottom. It complicates things somewhat. +1 on through-hole comments.
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1BUcKJVz5n34VwuiyiLtPud1PGn3BLkcPb :-)
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villex
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Mining hardware assembler and administrator.
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June 17, 2013, 06:40:13 PM |
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That being said, it's very easy to put the Avalon chips on the board by hand (using an iron or a hot-air rework gun). I could attach 16 QFN chips in less than 16 minutes.
Enigma
Unless you're working with an oven, that's a complete bullshit..
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TomKeddie
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June 17, 2013, 06:48:56 PM |
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BKK: I'm not sure if you saw it but Yifu posted on another thread (where someone got an Avalon clone board working with a sample chip) this: hint hint: the chip has a much higher clock cap. I don't think anyone knows details yet, so just an fyi. I hope he means capability and not capacitance! ps. lets close the thread above and keep this OT, we need to help BKK to focus.
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eros
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June 17, 2013, 07:50:51 PM |
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Hmm, they have samples in tray. I got samples in small blue box. Maybe bigger orders (20k? vs. 10k) have better samples Btw. Avalon-ref tell precalc needs on page 7. Pseudocode have for(í=0;i<64;i++) and if's i=0,1,2. Is three round precalc enough or miss I something? And asic's seems to go popular so difficulty rise. It renders K16 (&etc desings) too expensive (too much parts/cost per one asic). Sorry. Controller should have more IO lines to drive many asic chains. Like pic32MX795F512L 85pcs IO for ~8$. Asic chains should be longer. Avalon used 10pcs length K16 use 8pcs. What broblems can arise if asic chain are 16pcs lenght? How long it can be?
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Enigma81
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June 17, 2013, 08:21:38 PM |
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That being said, it's very easy to put the Avalon chips on the board by hand (using an iron or a hot-air rework gun). I could attach 16 QFN chips in less than 16 minutes.
Enigma
Unless you're working with an oven, that's a complete bullshit.. I'm not talking about in an oven - I'm talking about using a hot-air rework gun. If it took one of our rework techs more than two minutes to replace a QFN48, they'd be fired. Enigma
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TomKeddie
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June 17, 2013, 08:37:03 PM |
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Holy crap, there's a photo of an assembled board on ebay and BKK is still driving to pick his parts. This is a dog eat dog business for sure. No mention of a heatsink.
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trigeek
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June 17, 2013, 09:34:57 PM |
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Holy crap, there's a photo of an assembled board on ebay and BKK is still driving to pick his parts. This is a dog eat dog business for sure. No mention of a heatsink. The picture on ebay was downloaded directly from a thread here on bitcointalk and put up by some random person. It's not a functional board yet, all they did was use BKK's board specs and BOM to assemble one. Check the Terrahash and BKK threads for more details.
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roybitcoin
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June 17, 2013, 11:37:53 PM |
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Hi Bkk,
I´m looking at Nano sch and I guess that L1 must be tied to pin 3 (SW) instead of pin1 (BST) according to the AP6502A datasheet. Please confirm that.
Best regards!
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WynX
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June 17, 2013, 11:38:25 PM |
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Yes, but they are proving to be rather bitchy, at least without a proper PCB. Constructing the test harness for it took hours of very careful soldering under a microscope. Maybe my clock source has to much jitter, or the PLL core voltage is too noisy for it to lock. I will continue testing though.
Hmm seems the dead-bug style testing might not be very easy with this chip, at least for burnin there's currently some issues.
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FUKT
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June 17, 2013, 11:55:09 PM |
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Has anyone got a link for the I2C cables, having a little trouble sourcing them?
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villex
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Mining hardware assembler and administrator.
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June 18, 2013, 12:03:17 AM |
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I'm not talking about in an oven - I'm talking about using a hot-air rework gun. If it took one of our rework techs more than two minutes to replace a QFN48, they'd be fired.
Enigma
Please, stay on track with the thread.
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