AGC (Automatic Gain Control) provides automatic adjusting of gain in range 0…20 dB.
When amplitude of the input signal is more than some threshold then gain is decreasing rapidly from the current value down to 0 dB. When amplitude of the input signal is less than some threshold then gain is increasing slowly from current value up to +20 dB. Therefore, input signal with low level (-20 dB or higher) can be increased up to normal level and input signal with normal level (0 dB) cannot be distorted.
The AGC can be enabled or disabled with help of appropriate external parameter.
AGC depth can be changed by external parameter and can be set to one of 5 values: 20, 16, 12, 10 or 6 dB.