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jsanpe / c2c-64

A Composite & S-video to Component transcoder for the OSSC
MIT License
27 stars 3 forks source link

BOM Questions #3

Closed ezcGman closed 8 months ago

ezcGman commented 9 months ago

Hey there,

I'm currently collecting parts to build some of these awesome board (thanks for making these available!!).

I do have some questions about some parts:

Ferrite_Bead FB1,FB2,FB3,FB4,FB5,FB6 Inductor_SMD:L_0805_2012Metric

Do you have a bit more specs or an exact part number for these? LCSC (obviously) spits out a million results for just an inductor ;)

Crystal_GND24_Small Y1 Crystal:Crystal_SMD_3225-4Pin_3.2x2.5mm

This one is missing the frequency, do you have that by any chance?

33 RN1 RCJ-041:RESCAXE50P380X160X55-16N

I can't find this one anywhere with that part number. I guess from the looks and the "16N" it's some kind of multiplexer?

16Mhz Y2 Crystal:Crystal_C38-LF_D3.0mm_L8.0mm_Vertical
28.63 Y6 Crystal:Crystal_C38-LF_D3.0mm_L8.0mm_Vertical

Are those actually on the board still? I struggle to find them when looking at the gerbers in a gerber viewer. I was struggling to understand the package size / footprint of these, so I tried to find them on the board and see what they look lilke.

And on another note: In case you are using KiCad, I highly recommend using this plugin: https://github.com/openscopeproject/InteractiveHtmlBom

It's absolutely fantastic and generates interactive / HTML BOM files which are a tremendous help when soldering such a board. You can get an idea what they look like here (just download and open the HTML): https://github.com/ezcGman/lora-gateway/tree/master/pcbs/LoRa-Gateway-E32/ibom

Thanks and greetings,

Andy!

jsanpe commented 9 months ago

Hi, thanks for reaching out. Sorry about the poor state of the project, I unfortunately have little time these days to maintain/improve it. Regarding your questions:

I will try to use the plugin you recommend and push the output to github. I can't really commit to this, lot's of other stuff in my life right now.

jsanpe commented 9 months ago

It was easier than I expected: https://github.com/jsanpe/c2c-64/tree/master/hardware/1R/1R3/bom

ezcGman commented 9 months ago

Hi, thanks for reaching out. Sorry about the poor state of the project, I unfortunately have little time these days to maintain/improve it. Regarding your questions:

They're still in stock for me using that link, added them to the cart, thx!

  • For crystals, note that Y1 and Y6 are mutually exclusive. You should use one or the other, depending on availability. The freq is 28.636363Mhz. I have used this one in the past: C136080.

Oh ok. I just looked at the BOM, was there a note about that somewhere that I missed? I added the C136080 to the cart: https://www.lcsc.com/product-detail/Crystals_HELE-Harmony-Elec-X3S02863ADK1HA-X_C136080.html

  • The same applies to crystals Y2/Y3, you can choose either one. However, this crystal is not needed as the MPU internal oscilator is used by default. So, you can leave this (and the caps C46 and C47) unpopulated.

Ah ok. So that one is not even used at all? So there is really no need for it? I might just add it, because it's just a few cents, if there is the slightest chance for it to make any sense :)

  • RN1 is a resistor array. 33 ohm is recommended, but you can use something close to it if you don't find it. I actually have been using this part: C78520 which is 39ohm

Aaaaah yeah 🤦 That makes sense, thanks! LCSC doesn't have it in stock, will get it somewhere else.

Will continue adding everything to the cart, thanks already!!

Greetings,

Andy!

ezcGman commented 9 months ago

Some questions on the fuse:

Thanks!

jsanpe commented 9 months ago

For fuse I used this: C311043. 6V is a bit tight, but you can always replace it if it blows too easily. At 1.5A you should use a fast fuse. The board consumption should be in the few mA range (300mA tops) but it's always higher when you switch it on, that's the reason I allow for some extra amps. You may want to go for a slower fuse with lower amp rating.

About Y2/Y3 the current firmware does NOT use them. The internal atmega oscillator is accurate enough to allow for UART to work fine at slow speeds. For all other intents and purposes the accuracy of the oscillator is simply irrelevant, as the MPU is only there to configure the Video encoder and decoder ICs. My recommendation: do not populate.

ezcGman commented 8 months ago

For fuse I used this: C311043. 6V is a bit tight, but you can always replace it if it blows too easily. At 1.5A you should use a fast fuse. The board consumption should be in the few mA range (300mA tops) but it's always higher when you switch it on, that's the reason I allow for some extra amps. You may want to go for a slower fuse with lower amp rating.

I always use PTC / resettable fuses on boards, so no need to replace it ;) They work excellent, never had an issue with those so far. On spec and work as intended! Sadly they're only available in 6v with 1.5A, hence I'm double checking

About Y2/Y3 the current firmware does NOT use them. The internal atmega oscillator is accurate enough to allow for UART to work fine at slow speeds. For all other intents and purposes the accuracy of the oscillator is simply irrelevant, as the MPU is only there to configure the Video encoder and decoder ICs. My recommendation: do not populate.

Thanks, for the detailed explanation! I'll leave 'em off then :)

ezcGman commented 8 months ago

One more sadly :D Do you by any chance have a link to the buttons you used? There are a quadrizillion buttons out there and finding the ones you used with the spacing... it's close to impossible :D Thanks!

jsanpe commented 8 months ago

One more sadly :D Do you by any chance have a link to the buttons you used? There are a quadrizillion buttons out there and finding the ones you used with the spacing... it's close to impossible :D Thanks!

These little f$ckers are hard to find, tell me about it. Try these: C961730

ezcGman commented 8 months ago

Thanks for your extensive help!

I've ordered everything, most from LCSC and some connectors from AliExpress. I'm attaching the CSV of my LCSC order for people to easier re-order the components: export_cart_20240126_211354.csv

This CSV has all components to build five full boards! Why five: Because you anyways need to order five PCBs minimum and most components (resistors, caps, etc.) come in min 50 or even 100pcs minimum! So it just makes sense to go the extra few centimeters and also order the other missing parts and have five full kits that you can potentially resell / give to friends, etc. If you don't want that, adjust the quantities accordingly, mostly this is going to be the ICs, as again: Resistors and such have a 50 or 100s minimum order quantity.

The only things missing from that CSV / LCSC order are the jacks. I couldn't find them on LCSC and AliExpress is not that expensive, so I got them there:

Total price now for one board, incl. the PCBs with stencil: ~25-30€, depending on price changes and shipping :)

jsanpe commented 8 months ago

Thanks for your contributions! Let me know how it turns out

ezcGman commented 8 months ago

Will do! I've updated the CSV to now reflect the full components list, so people can just use that :) Closing this for now :)

whytheheckme commented 5 months ago

@ezcGman Did you ever get this up and running? Do you have spare parts you'd like to sell (particularly a PCB?)

ezcGman commented 5 months ago

@ezcGman Did you ever get this up and running? Do you have spare parts you'd like to sell (particularly a PCB?)

Jepp, I did: https://github.com/jsanpe/c2c-64/issues/5

And yeah, I do have complete (just missing the screen, but that is easy to get via AliExpress) left over kits I can sell. Because I bought parts for 5 kits directly, the price per kit is actually super low, it's just below 20€! I can spare one, if you want it? I'm in Germany, so depending on where you are, shipping costs may be the same as the price for the kit ;)

EDIT: One note though: You will still need to order the stencil from JLCPCB, PCBWay or any other PCB manufacturer of your choice. As I only have one and you'll 110% need it to solder this board.

That said: This board is definitely no beginner board to solder! You need some experience and tools (like a hot plate or at least a hot air station) to do this!

whytheheckme commented 5 months ago

And yeah, I do have complete (just missing the screen, but that is easy to get via AliExpress) left over kits I can sell. Because I bought parts for 5 kits directly, the price per kit is actually super low, it's just below 20€! I can spare one, if you want it? I'm in Germany, so depending on where you are, shipping costs may be the same as the price for the kit ;)

Amazing! I just finished pricing out all of the parts and the PCB, and I really don't need more than one, so I think it would be worth it. I live in the US but have an address in Denmark you can send it to where I will be in about 10 days (I found I could generate a label for 12€ but you may be able to get it even cheaper!)

Can you drop me a line? jake.at.spam (at) gmail Thank you!!

whytheheckme commented 5 months ago

@ezcGman Just wanted to follow up, I'd love to connect and buy a kit set from you.