| 摘要 |
In a circuit arrangement for setting the gain of an amplifier (V) with the aid of digital control signals (D1, D2, D3), a T-shaped resistor network (R2 to R8) is provided in the feedback circuit of the amplifier (V1), in which resistor network series resistors (R2, R3, R4) of the resistor network (R2 to R8) can either be shortcircuited, with disconnection of shunt resistors (R6, R7, R8) or can also be switched to be effective when the shunt resistors (R6, R7, R8) are switched to be effective, with the aid of separately controllable change-over switches (S1, 'S2, S3). As a result, the gain can be set in accordance with a logarithmic characteristic, the output resistance remaining the same. <IMAGE>
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