UTCTA8227AP LINEAR INTEGRATED CIRCUIT

QW-R107-021,A

APPLICATION INFORMATION AND APPLICATION METHOD

1. Adjustment of voltage gain

The voltage gain Gv is obtained as follows by R1, R2 and Rf in Fig.1

When Rf=0

Ω

Gv=56.5 dB (Typ.)

When Rf=120

Ω

Gv=45 dB (Typ.)

By increasing Rf, reduction of Gv is possible. However, since the feedback increase is liable to produce

oscillation, it is recommended to use this at 40dB or over.

2. Thermal shut-down circuit

The thermal shut-down circuit is built in for the purpose of preventing the destruction of IC due to the abnormal

temperature rise when the heat radiation is insufficient.

The operation temperature is set at radiation Fin temperature 175

°C (Typ.)

At this temperature or over the bias is interrupted to prevent the destruction of IC.

3. Input stage

The input circuit of this IC is as shown in fig.2. PNP Tr : Q1 is provided in the input circuit so as to make its usage

possible without the input coupling capacitor.

However, at pin 6 and pin 7, max 60mV offset voltage is produced.

Application after checking volume slide noise is recommended.