摘要 |
<p>An automatic gain control circuit (e.g. for use in a SECAM television receiver) comprising: an input node (2); an output node (40); controllable gain amplifier means (6) having a signal input (4) connected to the input node, a control input (24) and an output (8); automatic gain control means (20) having an input (18) coupled to the output of the controllable gain amplifier means and an output (22) connected to the control input of the controllable gain amplifier means; and divider means (30) having a first signal input (28) coupled to the output of the controllable gain amplifier means, a divide signal input (36) coupled to the input of the automatic gain control means and an output connected to the output node of the circuit, whereby the signal produced at the output of the divider means is substantially independent of the signal level produced at the output of the controllable gain amplifier means.</p> |