We have a LM4675 design that we had TI review. So far we can't get any audio out of it. I tied it's shutdown pin to VDD and hooked up a signal generator at the speaker_mono signal. I'm putting in a 1Vpp 1kHz sine wave. If I measure the output I see nothing, and I hear nothing. If I measure between C184 and R741 I see my sine wave, offset by a DC voltage. If I measure at pin 2 I see my sine wave but it is reduced in amplitude 2-3 times. What's strange is I see a matching sine wave on pin 1 which should have no signal. Since these two signals are matching in amplitude and phase, I assume that is why there is no output.
Now pin 1 and 2 are not shorted together, we measured. So I don't understand what's happening here? Any advice? Oh and VSYS is set to 4.0V right now, and we have a tiny 8ohm speaker connected across VO1 and VO2.
