Automatic gain control circuit

An RF tuner comprising:

• an automatic gain control circuit including a first automatic gain control unit arranged to adjust its gain in steps for operation on an input signal and to provide a control signal, and
• a second automatic gain control unit in cascade with the first automatic gain control unit and configured and arranged to adjust its gain based upon a feedback signal and according to a range-limited loop bandwidth, wherein the first and second automatic gain control units are circuits connected so as to adjust their gains in a synchronized manner according to the control signal by adjusting the loop bandwidth of the second automatic gain control unit;
• and
• a mixer configured and arranged as part of a first tuner or a second tuner, wherein the first automatic gain control unit is connected at an input of the first tuner, and wherein the second automatic gain control unit is connected to the second tuner.

An RF tuner comprising:

• an automatic gain control circuit including a first automatic gain control unit arranged to adjust its gain in steps for operation on an input signal and to provide a control signal, and
• a second automatic gain control unit in cascade with the first automatic gain control unit and configured and arranged to adjust its gain based upon a feedback signal and according to a range-limited loop bandwidth, wherein the first and second automatic gain control units are circuits connected so as to adjust their gains in a synchronized manner according to the control signal by adjusting the loop bandwidth of the second automatic gain control unit;
• and
• a mixer;
• wherein
• the second automatic gain control unit includes a transistor that adjusts the loop bandwidth and a feedback loop that provides feedback from an output of the second automatic gain control unit, and
• the first automatic gain control is configured and arranged to generate the control signal as a gate voltage that is applied to a gate of the transistor.

An automatic gain control circuit comprising

• a first automatic gain control unit arranged to adjust its gain in steps, and
• a second automatic gain control unit in cascade with the first automatic gain control unit and configured and arranged to adjust its gain based upon a feedback signal and a range-limited loop bandwidth,
• wherein the first and second automatic gain control units are circuits connected so as to adjust their gains in a synchronized manner, and
• wherein the first automatic gain control unit is configured and arranged to, in response to the gain of the first automatic gain control unit being adjusted, generate a control signal configured for adjusting the gain of the second automatic gain control unit by altering its loop bandwidth in response to the control signal, and communicate the control signal to the second automatic gain control unit to set the gain of the second automatic gain control unit, the second automatic gain control unit being configured and arranged to set its gain in response to the control signal, wherein the first automatic gain control unit is connected at an input of a first tuner, and wherein the second automatic gain control unit is connected to a second tuner.