Hello everyone! This is my first post in this forum, so please be gentle ;-)
I recently came across cmoy amp and lt1206-based virtual ground circuit. It caught my attention, so I built it from scratch and i don't understand why LT1206 is overheating (after several seconds of operation i can't touch it - it's too hot) - and i can hear 'clicking' sound every second or so in my headphones. It's based on popular tangentsoft website:
I've done some measurements. Circuit is powered from two 9V batteries. Virtual ground vs. rail voltages is perfectly split, but when 1206 overheats they become unstable. Power draw total is about 90mA. The component values are exactly the same as suggested at tangensoft website.
Is it possible it's just DIP8 (N8) version of 1206 that causes it to overheat (instead of TO22)? Or maybe it's oscillating? How can I diagnose the problem? All voltages seem to be fine. I also double checked all components - they work fine.
BTW why no one actually builds cmoy with LT1206 virtual ground? I can understand that it doesn't need >250mA current, but still it's one of better VGND circuits.