I believe LINEAR also has some papers on thermal barriers. They have nice thermal shots of how relatively large things perpendicular to the heat flow can cause problems. I don't believe it will cause much trouble here as the via's are almost in line with the heat dispersion.
Probably by hand, unless I get 50+ orders for full SMT builds, and there's no way I can do all the work without peeving people off with delays. I can probably build half a dozen boards a night on average.
Getting pick/place done means ordering the PCBs panelized, getting a big stencil made, having the assembly shop program the part shooter, etc... costs add up quick.
I'm tempted to give a toaster oven/skillet reflow approach a go, but I'd want to get more experience doing that before I attempt it on cards that I'm building for somebody else.
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Awesome... thanks for the info. Might give that a go. Target's closing here in Canada, I'll keep an eye out for a cheap/suitable toaster oven.
Then dear Sir,
Ladies and Gentlemen, I believe we have The Wiener!
Two birds, one stone as it were ... (see last comment on pic for lol ...)
😀
Just nudged the footprints around for the PLIMIT divider, you can put down two 0603 resistors or you can put down a 100K Bourns 3312 or equivalent sized pot.
Now I'm wondering if I should just leave the pot there full-time. It'll cost an extra buck.
Now I'm wondering if I should just leave the pot there full-time. It'll cost an extra buck.
I cannot speak for others but if that make live (yours and/or ours) easier , I'll happily pay for it.
Regards,
OT:
Well, the RF radiation is mainly via the connection wires.
Shown here:
TPA3132D2 vs. MAX9709 measurements EMI / EMC - # 360customs
"20-200Mhz with load"
As you see, the MAX9709 performs much much better.
BOM mostly finalized, spreadsheet's coming together, I'll have costs tonight.
I'm picking/choosing different parts across Digikey/Mouser - it's amazing how much pricing variation you get across different suppliers for different things, terminal blocks are pretty much half price at Digikey compared to Mouser for example.
Because I'm pulling from 2 different suppliers, getting quantity discounts and spreading shipping costs across everyone's order, it might end up being cheaper to order a fully built card from me than to order a bare PCB and obtain your own parts from Mouser alone...
I'm picking/choosing different parts across Digikey/Mouser - it's amazing how much pricing variation you get across different suppliers for different things, terminal blocks are pretty much half price at Digikey compared to Mouser for example.
Because I'm pulling from 2 different suppliers, getting quantity discounts and spreading shipping costs across everyone's order, it might end up being cheaper to order a fully built card from me than to order a bare PCB and obtain your own parts from Mouser alone...
Also, only Mouser carries the Ice Components inductors, and only Digikey carries the thermal pad for heatsinking the PCB to an enclosure.
So I'll probably split the BOM in two and offer a couple more options:
- "Digikey-only BOM" - bare PCB (optionally with 3118) + class D inductors, buy all your parts from DK.
- "Mouser-only BOM" - bare PCB (optionally with 3118) + thermal pad, buy all your parts from Mouser.
So I'll probably split the BOM in two and offer a couple more options:
- "Digikey-only BOM" - bare PCB (optionally with 3118) + class D inductors, buy all your parts from DK.
- "Mouser-only BOM" - bare PCB (optionally with 3118) + thermal pad, buy all your parts from Mouser.
I have the same issue with suppliers, the worst is Elektor projects where someone uses a specific mechanical comp ( i.e switch) that is only available from say Newark (PITA). The LCR meter project comes to mind.
Nice to see you are going to try the ICE inductors. I was going to use "911-1D14A-100M". I wonder if you are going to use this one or the higher power ones. I specified it for the TPA3116.
If you want to post or PM me the gerber/drill data I can look it over for you = sanity check!! I use gerbtool.
Nice to see you are going to try the ICE inductors. I was going to use "911-1D14A-100M". I wonder if you are going to use this one or the higher power ones. I specified it for the TPA3116.
If you want to post or PM me the gerber/drill data I can look it over for you = sanity check!! I use gerbtool.
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I will jump on the occasion to buy a full PCB, if it is built to suit a Feastrex 5",driver, 94db sensitivity, 15min. 25 max. RMS, 16 ohms impedance Full Range speakers.
I'm using 1D14A-100M - I got hold of the L versus I curve and it's flat up to 8-9 amps, only drooping 10% at 11A - well beyond the 6A you'll run through the thing at 24V into a 4 ohm load, and giving plenty of margin for delta-IL and impedance droop. And it doesn't take up much space on the PCB, it's much smaller than a DR127-100R or comparable SMT inductor. Pretty much perfect for the application.
I've got access to gerbtool also, thanks for the offer.
Sounds good - if you want, I'll modify the output filter L/C values to suit the 16 ohm load.
16 ohm minimum impedance, so with Zobel Feastrex is 16 ohm, without probably over 100 ohm at filterfrequency (40khz), adjustable switchingfrequency of this board could be helpfull getting massive peak further away I guess
This is the information i have gathered in time to try to zero in on the driver efficiencies or lack of. Hope there is good information in the photos.
thank you.....
PS i should have added this one also which seem to be more relevant to...
thank you.....
PS i should have added this one also which seem to be more relevant to...
Attachments
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Perfect - knowing the Re/Le values lets me calculate a snubber specifically for it, and then calculate the LC filter so there won't be any peaking.
Sounds promising, so i will order a full PCB assembly to match the drivers that i have and also... can you add to the order, a PCB with chip installed and tested of a TPA3118 board so i can customize it at will if needed.
Cheer for the Maritime guys
Cheer for the Maritime guys
So I've got a BOM put together, to use for a cost estimate.
Assuming that I'm building 25 fully assembled cards, the cost of the bare parts is just under $42 CAD. This is the straight summed up costs of all parts, taken straight off the Digikey and Mouser sites, without any taxes/shipping/duty/etc in the price. There's no single big expense that drives the price that high, rather a whole lot of smaller ones - the 4 class D inductors are $8.68, the TPA3118 is $4.20, the four 2.2u input film caps are $3.62, the pair of 82uF/35V polymer electrolytics are $3.69, the 8 pin rising cage terminal block is $3.09, thermal pad and 1/8" standoffs work out to about $4.45 if you want that option, etc...
Assuming I pay $50 in duty/shipping to get everything here, $60 for the two test jigs and 15% HST on the works, the total parts cost for a single PCB works out to just under $54 CAD.
This doesn't include the PCB ($8), and going by the $25 assembly labor cost quoted earlier, $8+$54+$25 = $87/card for a completed PCB. For a PCB with the TPA installed... "taxing" the $4.20 TPA with shipping/duty/test jigs/etc via the same method brings its cost up to $5.50, so $8 (PCB) + $7 (labor) + $5.50 = $20.50 CAD.
These arent final costs, I'm sure I've forgotten a few things, and I haven't gone exhaustively through the Mouser/Digikey sites looking for even better deals on parts.
So yeah, it'll cost more than your average eBay board. Hopefully that doesn't sticker shock too many people...
Assuming that I'm building 25 fully assembled cards, the cost of the bare parts is just under $42 CAD. This is the straight summed up costs of all parts, taken straight off the Digikey and Mouser sites, without any taxes/shipping/duty/etc in the price. There's no single big expense that drives the price that high, rather a whole lot of smaller ones - the 4 class D inductors are $8.68, the TPA3118 is $4.20, the four 2.2u input film caps are $3.62, the pair of 82uF/35V polymer electrolytics are $3.69, the 8 pin rising cage terminal block is $3.09, thermal pad and 1/8" standoffs work out to about $4.45 if you want that option, etc...
Assuming I pay $50 in duty/shipping to get everything here, $60 for the two test jigs and 15% HST on the works, the total parts cost for a single PCB works out to just under $54 CAD.
This doesn't include the PCB ($8), and going by the $25 assembly labor cost quoted earlier, $8+$54+$25 = $87/card for a completed PCB. For a PCB with the TPA installed... "taxing" the $4.20 TPA with shipping/duty/test jigs/etc via the same method brings its cost up to $5.50, so $8 (PCB) + $7 (labor) + $5.50 = $20.50 CAD.
These arent final costs, I'm sure I've forgotten a few things, and I haven't gone exhaustively through the Mouser/Digikey sites looking for even better deals on parts.
So yeah, it'll cost more than your average eBay board. Hopefully that doesn't sticker shock too many people...
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