Patent ID: 7323922
Filing Date: 2008-01-29
Classification: H03G

Abstract:
1. Gain control circuitry for controlling the gain of a signal path, the gain control circuitry comprising: comparator circuitry configured to receive a first analogue input and provide a first digital output in response to receiving the first analogue input having a value greater than an upper threshold value or less than a lower threshold value; a bi-directional counter configured to provide a digital gain control signal to a digitally controlled gain device and configured to change the value of the digital gain control signal in response to receiving the first digital output from the comparator circuitry; a digital-to-analogue converter configured to convert the digital gain control signal to a first analogue output signal; a subtractor configured to receive the first analogue output signal from the digital-to-analogue converter and an analogue gain control signal and to provide a second analogue output signal representative of the difference between the value of the first analogue output signal from the digital-to-analogue converter and the analogue gain control signal, the second analogue output signal being provided as the first analogue input to the comparator circuitry.