c2 3 *C IN IN - 1 Rf1 C1 47uF 82 C3 IN1 6 NF1 5 30 + ch - 1 - 20K Ripple BIAS CIRCUIT 4 THERMAL SHUT DOWN PROTECTION CIRCUIT 220uF *C IN IN - 2 Rf2 C2 47uF 82 IN2 7 NF2 8 30 + ch - .