Programmable digital gain circuit and corresponding method

The grading circuit can be used to compensate a data signal attenuation for transmitting medium with. The control circuit for balancing circuit capable of the control input of averaging table, wherein a control to the data signal gain quantity. The comparator can determine according came from the gain of balancing circuit for compares increase the insulating is less or more of. Programmable/added in the counter is fixed to the bottom of the output adjusting counting value of comparator. The counting value is connected with one or more digital-to-analog converter conversion is one or more analogue voltages. The analogue generating capable of controlling input is provided on the table averaging. The control circuit is further connected to a cover circuit, which is a gain for averaging stage is closely the gain quantity of needed, wherein prevented to the counting value is adjusted.