摘要 |
A variable gain control system for a digital signal is provided in which the digital signal addresses a digital memory to produce an output signal representative of the addressing signal modified by a transfer characteristic. A control word M is repetitively loaded into an M counter, which counts to a predetermined limit to produce output pulses when the limit is reached. The output pulses increment a data counter. Concurrently, an N control word is repetitively loaded into an N counter, which also counts to a predetermined limit to produce output pulses when that limit is reached. The output pulses of the N counter increment an address counter. When the count of the address counter changes, the current value of the data counter is loaded into a digital memory at the address provided by the address counter. The memory is loaded in this manner to store a data array representative of a signal gain related to the ratio of the N to M. |