SUM

CD8227GP

SUM

3/8

TEST CI RCUI T & BLOCK DIAGRAM

*(1) This IC can be used without coupling capacitor (CIN),If volume slide noise occurred by

input offset voltage is undesirable, it needs to use the capacitor(CIN).

*(2) The condenser between the ④ pin and the GND(C 11)is for reducing pop noise when th e

power ON/O FF switch (S W1)is set to ON/OF F.

APPLI CATION INFORMATION AND APPLICATION M ETHOD

1. ADJUSTMENT OF VOLTAGE GAIN

The voltage gain Gv is obtained as follows

by R1,R2 and Rf in Fig.1.

Gv=20log((Rf+R1+R2)/(Rf+R1))

When Rf=0

Gv=56.5dB(Typ.)

When Rf=120Ω

Gv=45dB(Typ.)

By increasing Rf , reduction of Gv is possible ,

However, since the feedback

Fig 1.

increase is liable to produce oscillation , it is recommended to use this at 40dB or

over.