Hello. I purchased 4-5 PCM2912A (PCM2912A, 103XLT on the chip) chips through digikey two months ago, and I'm having a very hard time trying to get it to work. I simply need to have it working in standard, typical fashion. Seeing the typical circuit connection schematic in the datasheet, I tried to breadboard the chip (after home-etching and successfully testing for faults a breakout board for it). While I didn't have the exact value for each & every component, I did have them near enough to do the job. And it did - about once in a hundred tries.
What I mean is that the codec successfully enumerated only once after many tries. I thought that maybe I had some component values wrong, or perhaps hadn't connected some essential components. So I tinkered more and got it to work. I use Windows XP SP2, and the codec definitely showed up in my volume settings, and the led blinked when I played some music through it. But when I disconnected & reconnected, it failed to enumerate/detect! Windows gave me a device not recognized error box! And it continued to do so for many repeated attempts. I kept thinking that perhaps I had some loose connection in my breadboard circuit somewhere. But I checked with a multimeter and there didn't seem to be any. I checked and rechecked my circuit many times in various aspects, and trying to add (or remove) many components in sheer desperation to make it work, and it did a few times but never in successive tries. I concluded that maybe my breadboard indeed had a fault somewhere inside and so I went ahead recently to etch a single sided board for the IC. After the etching and soldering, I tested for continuity and all was OK. I plugged the usb cable back into my computer but my OS still didn't detect the codec chip! The chip works/gets-detected once in many tries, once again. When the codec is detected, after every little modification I make to the board, I'm overjoyed, thinking I may have finally found and repaired the problem. But after a disconnection and then a reconnection, it never works! I've tried replacing the inductor on pin 1 by a short, I've tried loading the headphone/speaker connections (with a 1k resistive load) just in case its necessary, I've tried replacing the 6MHz crystal + loading caps with a 3-pin 6Mhz resonator, I've tried replacing the ripped USB cable too, but so far I've observed no concrete direction as to why the codec refuses to function. It just functions out of the blue when it wants to, for no apparent reason, and then refuses to successfully connect again when I take out the usb connector and put it back in.
It's a very frustrating cycle. I can't seem to find the solution as to why this is happening. The "Solving Enumeration Errors in USB Audio DAC and CODEC Designs" application note has been unhelpful as well as there's been no mention of inconsistent enumerations. Like I said, the codec successfully connects occasionally but fails to connect right after, even though I've made no changes to the circuit whatsoever.
Please help me out. Am I constantly overlooking something really trivial, or is there a fault with the set of chips I've received? I'm aware of troubleshooting blues, but this once has been extraordinarily problematic.
Also, the power pins (Vdd, VccR etc) all are functional even when the codec hasn't successfully connected. SSPND' is low, however, unless if the codec has successfully connected.
Here is the list of values I used for the last time the circuit did run. I haven't altered any of these yet. All the remaining parts are as they're mentioned in the typical circuit connection diagram.
-1k resistive load on both headphone outs
-POWER (pin 24) is grounded. (The codec has also worked in the past when this pin was connected to VCCP)
-SSPND', MUTE, VIN and MBIAS (pins 29, 30, 16, 17) left floating/unconnected.
-R12 R13 are 1k each
-L1 is 0uH (short)
-R1 R2 are 33R each
-C2 C3 are 30pF ceramics each
-C4 C5 are 270pF each
-C6 is 4.7uF
-R7/8/10/11 are 2.7k each
PS: I don't believe my system is at fault. I tried connecting to a friend's laptop, running Win7, and it failed to connect there as well.