A PCB design for the PCM2900
Stereo codec chip
The PCM2900 codec chip was featured in the August 2011 edition of Radcom by Andy Talbot G4JNT.
I have designed a PCB for the PCM2900, the only SMD is the chip; all other components are through hole components.
I have tested the finished soundcard with my Acorn SDR receiver and it works very well.
Eventually i will build the PCM2900 PCB into the Acorn, then the only connection to the PC will be the USB cable.
Above is the view of the copper side of the PCB with the PCM2900 soldered in place.
Below is the component side view of the PCB.
Click here and you can download the component overlay for the PCB.
The PCB foil pattern is here for anyone who wants to make their own circuit board.
Soldering the chip on to the board seems a bit daunting but it's not that bad providing you have the right equipment.
For those of us who are the wrong side of 60 you will definitely need a magnifier; come to think of it so will those of you who are the right side of 60, hi. I use the headband type but the choice is yours.
You will need a soldering iron with a fine tip and reel of de soldering braid and some fine gauge solder.
Line up the PCM2900 chip with pin 1 in the right location on the PCB and stick it down with Bluetack, when your happy that it's lined up solder pin 1 to the track; re-check and make sure that the chip hasn't moved, if all is ok solder pin 15 to the track; again make sure all is lined up.
When your happy that all is ok solder all the other pins to the tracks, at this point you will be thinking oh god i've bridged every pin with solder, "don't panic" with your solder braid suck up the excess solder from the pins and tracks, when you have done this check and make sure that you haven't missed any bridges; if all is ok you can carry on and populate the rest of the PCB with the through hole components.
Testing is simple, just wire up the USB cable and plug it into your PC; if it's working the PC will detect it and load the drivers.
When this is done you will need to check that the inputs and outputs are working, i just used the Winrad SDR software and my Acorn receiver, job done; a nice little soundcard to build into a future project.
73, Colin G0NQE