| 摘要 |
A current control circuit for a muting circuit including a current mirror circuit formed of first and second transistor devices, one of which being operative to receive a controllable current and the other being operative to conduct a current whose value is determined by and changeable with the controllable current, such other transistor device being adapted to be connected to a load. A constant current generator generates a substantially constant current and is connected to a current-responsive circuit which, in turn, supplies the controllable current to the first-mentioned transistor device included in the current mirror circuit. A variable conducting circuit is coupled to the constant current generator for conducting a selectively variable amount of the constant current such that the level of the controllable current which is supplied to the first-mentioned transistor device is established in accordance with the difference between the constant current and the current conducted by the variable conducting circuit. Thus, the current through the current mirror circuit, and thus the load current, is determined by the conductivity of the variable conducting circuit. |
