Abstract: A radio frequency tuner is provided for selecting channels from a cable distribution network or other reception system. The tuner has one or more stages whose performance, such as signal to noise plus intermodulation, and gain are functions of the stage power consumption. A comparator compares the tuner performance, such as bit error rate, with a predetermined performance. When the tuner performance exceeds the predetermined performance, a power consumption control circuit reduces the power consumption of one or more of the stages so as to reduce the tuner power consumption while maintaining acceptable tuner performance. As an alternative, the control circuit may have an input which allows the power consumption to be preset in accordance with the tuner application. The control circuit also controls a variable gain arrangement to compensate for changes in gain resulting from changes in power consumption.

Abstract: A signal handling stage provides variable gain, for example for automatic gain control functions, in a radio frequency tuner. The stage comprises a transconductance stage having negative feedback via further transconductance stage. The output current of the transconductance stage is supplied to an AGC core, which steers the output current between output loads and loads for driving the transconductance stage in accordance with an AGC voltage. The amount of negative feedback is therefore varied in accordance with the AGC voltage. For relatively low gain, a large amount of feedback is used and this improves the distortion performance. For relatively high gain, the negative feedback is reduced but a good noise figure can be achieved.

Abstract: A system and method are provided for designing and manufacturing a semiconductor device, such as part of an integrated circuit. A template comprising a basic circuit diagram of a discrete circuit block and corresponding design equations are selected from a library. Desired performance parameters are selected and the value of one or more components of the circuit block are determined to allow the block to achieve the desired performance parameters.

Abstract: A signal handling stage provides variable gain, for example for automatic gain control functions, in a radio frequency tuner. The stage comprises a transconductance stage having negative feedback via further transconductance stage. The output current of the transconductance stage is supplied to an AGC core, which steers the output current between output loads and loads for driving the transconductance stage in accordance with an AGC voltage. The amount of negative feedback is therefore varied in accordance with the AGC voltage. For relatively low gain, a large amount of feedback is used and this improves the distortion performance. For relatively high gain, the negative feedback is reduced but a good noise figure can be achieved.

Abstract: A radio frequency tuner is provided for selecting channels from a cable distribution network or other reception system. The tuner has one or more stages whose performance, such as signal to noise plus intermodulation, and gain are functions of the stage power consumption. A comparator compares the tuner performance, such as bit error rate, with a predetermined performance. When the tuner performance exceeds the predetermined performance, a power consumption control circuit reduces the power consumption of one or more of the stages so as to reduce the tuner power consumption while maintaining acceptable tuner performance. As an alternative, the control circuit may have an input which allows the power consumption to be preset in accordance with the tuner application. The control circuit also controls a variable gain arrangement to compensate for changes in gain resulting from changes in power consumption.

Abstract: A system and method are provided for designing and manufacturing a semiconductor device, such as part of an integrated circuit. A template comprising a basic circuit diagram of a discrete circuit block and corresponding design equations are selected from a library. Desired performance parameters are selected and the value of one or more components of the circuit block are determined to allow the block to achieve the desired performance parameters.