No need to give me any praise. I have to thank the heck out of everyone on here for buying my random little card, spending several times what they'd spend on a "basically does the same thing" TPA card off aliexpress/ebay.
I'll be honest... we built a home business here last year, and sunk a bunch of money into a new shed that we built on the property where the girlfriend now runs a dog boarding and daycare business. Things are a bit tight right now while we're paying everything off, and our dog Charlie getting a leg tumor came out of nowhere and the vet bill was ~$1400 CAD. This group buy came at just the right time and it's paid off most of that.
The dining room table is still covered in electronics, and I've still got a heck of a lot of work ahead of me to finish these things and get them mailed out... but I'm grateful as heck I'm doing it. Thank you all so much.
The rev2 PCB's came today. Time to bang out some 4 ohm boards... at the very least I'll mail out bk856er's PCBs/uCs/inductors and a card for cogitech tomorrow.
I'll be honest... we built a home business here last year, and sunk a bunch of money into a new shed that we built on the property where the girlfriend now runs a dog boarding and daycare business. Things are a bit tight right now while we're paying everything off, and our dog Charlie getting a leg tumor came out of nowhere and the vet bill was ~$1400 CAD. This group buy came at just the right time and it's paid off most of that.
The dining room table is still covered in electronics, and I've still got a heck of a lot of work ahead of me to finish these things and get them mailed out... but I'm grateful as heck I'm doing it. Thank you all so much.
The rev2 PCB's came today. Time to bang out some 4 ohm boards... at the very least I'll mail out bk856er's PCBs/uCs/inductors and a card for cogitech tomorrow.
Lo_Tse: I probably won't attempt to hand-build 50 amps again 
but I'll definitely bang out another round given enough interest. I'll probably attempt a solder paste/reflow method to speed things up and make the finished product look a little better.
Cogi: Left your board at home by accident yesterday, it's getting mailed out tomorrow when the PO is open again. It'll be sent xpresspost.
Charlie's doing great:
He's 100% back to normal and his fur's halfway grown back already. They couldn't remove some of the fatty tumor around his sciatic nerve so it might come back eventually, hopefully that takes a long time if it does.
but I'll definitely bang out another round given enough interest. I'll probably attempt a solder paste/reflow method to speed things up and make the finished product look a little better.Cogi: Left your board at home by accident yesterday, it's getting mailed out tomorrow when the PO is open again. It'll be sent xpresspost.
Charlie's doing great:
He's 100% back to normal and his fur's halfway grown back already. They couldn't remove some of the fatty tumor around his sciatic nerve so it might come back eventually, hopefully that takes a long time if it does.
Current status...
Sent:
bk856er, goo, andrewcorbett, vanofmonks, pronk, gabbar
Sending out tomorrow:
impuls60, aterren, shadowlight, cogitech, zoidbergslo, finneybear, kp93300, msavage
uline and mounting kit hardware orders are made. I ran out of 10 ohm resistors (ordered 4/board, needed 5/board) so dwpeterson, and alanL's boards (last boards built) are held up until I get more of those, gonna see about sneaking them in with a company digikey order tomorrow at work.
Sent:
bk856er, goo, andrewcorbett, vanofmonks, pronk, gabbar
Sending out tomorrow:
impuls60, aterren, shadowlight, cogitech, zoidbergslo, finneybear, kp93300, msavage
uline and mounting kit hardware orders are made. I ran out of 10 ohm resistors (ordered 4/board, needed 5/board) so dwpeterson, and alanL's boards (last boards built) are held up until I get more of those, gonna see about sneaking them in with a company digikey order tomorrow at work.
Mailing out tomorrow morning:
- afoor's PCB's/uC's
- goo's amp
- matt_garman's amp
- andrewcorbett's amp, I need your mailing address
Hi Gary,
I got it!
I haven't had a chance to power it up yet, but quick question: is "R11" supposed to be open? On mine, there is a solder drop on one pad, but the other pad is clean. Just want to make sure that's supposed to be that way.
Thanks!
That was quick! Normally 'small packet air' takes a week and a bit. Other people's cards should start showing up pretty soon now.
Unfortunately there's supposed to be a 30.1K resistor in the R11 spot, either I forgot to solder the part there and missed it, or I tacked one side of the resistor during assembly and forgot to finish soldering it, and it fell off during shipping (check the static bag, there might be a loose part in there)
The amp works fine without it, but the PLIMIT feature is disabled - R11 pulls the counterclockwise leg of RV1 (PLIMIT pot) to ground, omitting the resistor means PLIMIT=GVDD. If you want the feature, just put a solder blob or piece of wire across the R11 footprint, it'll be fine. Or I'll fire off a resistor in an envelope. Or if you've got some 0603 resistors kicking around, toss down something in the 10k-33k range.
I put the resistor there mainly to obey the "maximum 50k loading on GVDD" recommendation, since the worst case resistance of the GAINSLV DIP switch divider is 80k. With a solder blob in the R11 location the resistance on GVDD is 44k with the DIP switches set to worst case. Considering the pin is the gate drive supply for the chip (and I'm pretty sure gate drive takes more current than a 44k resistor...) and worst case tolerances on the parts used on TI's own EVM can push it to 42k, you'll be fine.
Apologies again for that. Every one of these boards is "listening tested" after being built, but that one made it through.
Unfortunately there's supposed to be a 30.1K resistor in the R11 spot, either I forgot to solder the part there and missed it, or I tacked one side of the resistor during assembly and forgot to finish soldering it, and it fell off during shipping (check the static bag, there might be a loose part in there)
The amp works fine without it, but the PLIMIT feature is disabled - R11 pulls the counterclockwise leg of RV1 (PLIMIT pot) to ground, omitting the resistor means PLIMIT=GVDD. If you want the feature, just put a solder blob or piece of wire across the R11 footprint, it'll be fine. Or I'll fire off a resistor in an envelope. Or if you've got some 0603 resistors kicking around, toss down something in the 10k-33k range.
I put the resistor there mainly to obey the "maximum 50k loading on GVDD" recommendation, since the worst case resistance of the GAINSLV DIP switch divider is 80k. With a solder blob in the R11 location the resistance on GVDD is 44k with the DIP switches set to worst case. Considering the pin is the gate drive supply for the chip (and I'm pretty sure gate drive takes more current than a 44k resistor...) and worst case tolerances on the parts used on TI's own EVM can push it to 42k, you'll be fine.
Apologies again for that. Every one of these boards is "listening tested" after being built, but that one made it through.
I will wait to the end.
why? you waiting for the 'problem child' PCB, the one nobody could get working.
It's not in the static bag, but it could have fallen out before I realized there was a problem. But from the look of it, I think it was simply omitted, as the solder blob on the one pad looks like a perfectly unblemished circle.
That explanation is over my head, so I'm not sure if I want the feature or not. Any chance you could dumb it down for me?
I have some extra SMD resistors left over from my DUG build, but I think those are all bigger than 0603. I'll check though. If we lived in the same country I'd probably take you up on the mailing offer, but I hate to have you pay for international mailing for something so trivial.
I think I'll just live without it until my next Mouser or DigiKey order.
No problem, I totally understand! Still looking forward to firing it up, though waiting on a lot of other parts before I can build it up.
It'll cost about a buck to mail, don't worry about it.
As for what PLIMIT does, see section 7.3.4 in the TPA datasheet: http://www.ti.com/lit/ds/symlink/tpa3116d2.pdf
I'm sure 99% of people won't use this feature, but it's there for completeness
As for what PLIMIT does, see section 7.3.4 in the TPA datasheet: http://www.ti.com/lit/ds/symlink/tpa3116d2.pdf
I'm sure 99% of people won't use this feature, but it's there for completeness