I have two amp3 boards, four TA2021B chip, and nothing works. Therefore after much soldering, and making matter worse through every effort I have come to some conclusions. First that from now on I am going to start every board by soldering on the chip first using an oven. This should end the needless problem of removing solder from pins, and making things look like a holly mess. Second, I have concluded you have one shot at soldering on a chip to a board, after lifting pads and using small wires to fix and remake the connnections, I feel it is just not worth it to try to resolder new chips on boards.
The upside is that I have eight beautifully wound torroid chokes that I can transfer onto new boards when I get them from Jan. I figure all this soldering has been at the least an education on soldering these things. I am quite stuborn and refuse to give up and move on to another board, until I at least get one working amp3. At $25 a pop it really isn't all that bad, I just figure I am going to continue ordering boards and assemlbing them until I get one to work.
The ego deflating part is that I have assembled so many SMD board in the past and they have all worked, not one has had the problems I am having with these. I don't know if it is because of the double copper thickness or what, but they just don't go like all the others, and all the other surface mount chips I have soldered. The funnest thing is the first amp3 I built it took me two hours to put together, and it worked right off and for several days (on my bench) until I put it in a chassis.
I am itching to get to work on an amp5, but want to at least get this amp3 working with this beautiful chassis I made for it.
Frustrated but not discouraged,