Electronic – Tiny, cheap audio buffer with mute


I need to buffer an audio signal (feeding into a variable input impedance), and make it mutable with a digital control. The best thing I can think of is an op-amp (maybe TS971? 3×2 mm SOT23) feeding into an analog switch, like NLAS4599 (3×3 mm TSOP-6), but this requires several external components (example circuits).

Anyone know of anything better? A tiny IC that acts as both a unity-gain buffer and a digitally-controlled mute? Supplies are 4.5 V and ground, signal is biased to half that, and the mute and unmute transitions should be pop-free.

Best Answer

Would any old op-amp/buffer with a shutdown signal be sufficient? Digikey has TONS of options if this is acceptable. MAX9812 is a SC70-6 package, for example. (Not a buffer. LMV341 is a single op-amp with shutdown in an SC70-6 package.)