Abstract: A circuit, set forth by way of example and not limitation, includes a signal detector operative to detect two types of signals, where the two types of signals include a higher-frequency signal and a lower-frequency signal. The signal detector is operative to detect that a received input signal is one of the two types of signals. An output driver is operative to receive the input signal and to adjust conditioning performed on the input signal to create an output signal for transmission over a communication channel, where the adjustment is based on the detection by the signal detector.

Abstract: An adaptive equalizer circuit, set forth by way of example and not limitation, includes a plurality of paths receiving an input signal. One or more equalizers are each provided on one of the paths and are operative to equalize signal amplitude. An equalizer selector receives the input signal and is operative to output a selection signal based on higher-frequency content and lower-frequency content of the input signal. The selection signal is operative to select one of the paths to output an output signal that is based on the input signal.

Abstract: An adaptive equalizer circuit, set forth by way of example and not limitation, includes a plurality of paths receiving an input signal. One or more equalizers are each provided on one of the paths and are operative to equalize signal amplitude. An equalizer selector receives the input signal and is operative to output a selection signal based on higher-frequency content and lower-frequency content of the input signal. The selection signal is operative to select one of the paths to output an output signal that is based on the input signal.

Abstract: A method and apparatus to provide blooming protection for a pixel in an array while extending dynamic range.

Abstract: Disclosed are a multi-stage amplifier circuit, a method of operating a multi-stage amplifier circuit, and a device with the multi-stage amplifier circuit. The amplifier circuit technology includes an operational amplifier shared among multiple stages and switching circuitry. The various switching circuitry switches among elements to provide different input signals and different feedback to the shared operational amplifier at the different stages of operation of the amplifier circuit. The various switching circuitry also stores and discharges charge at one or more operational amplifier inputs.

Abstract: A resistor detection circuit configurable for coupling to an external resistor of an integrated circuit or other type of circuit includes at least one internal resistor, and comparison circuitry associated with the internal resistor. The comparison circuitry is operative to generate, based at least in part on a value of the external resistor, an output indicative of a value of the internal resistor. The output generated by the comparison circuitry may comprise an encoded digital output signal representative of the value of the internal resistor.

Abstract: A programmable voltage-controlled oscillator includes a ring oscillator having a number of selectable delay stages, and a resistor value detection circuit configurable for coupling to an external resistor. The resistor value detection circuit includes at least one internal resistor and is operative to generate, based at least in part on a value of the external resistor, an output signal indicative of a value of the internal resistor. The output signal is utilizable in controlling an oscillation frequency of the ring oscillator based at least in part on selection of one or more of the selectable delay stages. The voltage-controlled oscillator may be utilized in a phase-locked loop of clock recovery circuit in an integrated circuit, and in numerous other applications.

Abstract: A transconductance control circuit includes a master device having first and second field effect devices coupled to respective first and second current sources, a reference device coupled to a third current source, and comparison circuitry. The comparison circuitry includes at least first, second and third inputs and at least one output, with the first input configured to receive a reference signal associated with the reference device, the second and third inputs coupled to respective terminals of the first and second field effect devices, and the output coupled to current control inputs of one or more of the current sources. The transconductance control circuit provides a feedback control arrangement in which, for example, the comparison circuitry output is utilized to adjust one or more of the current sources such that a difference signal Vg between voltages at the respective terminals of the first and second field effect devices converges to a reference signal VR.

Abstract: A resistor detection circuit configurable for coupling to an external resistor of an integrated circuit or other type of circuit includes at least one internal resistor, and comparison circuitry associated with the internal resistor. The comparison circuitry is operative to generate, based at least in part on a value of the external resistor, an output indicative of a value of the internal resistor. The output generated by the comparison circuitry may comprise an encoded digital output signal representative of the value of the internal resistor.

Abstract: A programmable voltage-controlled oscillator includes a ring oscillator having a number of selectable delay stages, and a resistor value detection circuit configurable for coupling to an external resistor. The resistor value detection circuit includes at least one internal resistor and is operative to generate, based at least in part on a value of the external resistor, an output signal indicative of a value of the internal resistor. The output signal is utilizable in controlling an oscillation frequency of the ring oscillator based at least in part on selection of one or more of the selectable delay stages. The voltage-controlled oscillator may be utilized in a phase-locked loop of clock recovery circuit in an integrated circuit, and in numerous other applications.

Abstract: A transconductance control circuit includes a master device having first and second field effect devices coupled to respective first and second current sources, a reference device coupled to a third current source, and comparison circuitry. The comparison circuitry includes at least first, second and third inputs and at least one output, with the first input configured to receive a reference signal associated with the reference device, the second and third inputs coupled to respective terminals of the first and second field effect devices, and the output coupled to current control inputs of one or more of the current sources. The transconductance control circuit provides a feedback control arrangement in which, for example, the comparison circuitry output is utilized to adjust one or more of the current sources such that a difference signal Vg between voltages at the respective terminals of the first and second field effect devices converges to a reference signal VR.

Abstract: A phase-locked loop (PLL) includes at least first and second loops, and loop selection circuitry coupled to the first and second loops, the loop selection circuitry being responsive to at least one loop select signal to control transition from an operating mode of one of the first and second loops to an operating mode of the other of the first and second loops. In an illustrative embodiment, the PLL comprises a dual-loop PLL with the first and second loops corresponding to respective frequency and phase loops, and the loop selection circuitry is configured such that the loop select signal as applied to a control input of a current-generating component of the first loop represents a delayed and inverted version of the loop select signal as applied to a control input of a current-generating component of the second loop.

Abstract: A linear phase detector includes first, second and third latches connected in series, each of the latches having a data input, a data output and a clock input, and further includes reference signal generation circuitry and error signal generation circuitry. The reference signal generation circuitry has at least a first input coupled to the data output of the second latch and a second input coupled to the data output of the third latch. The error signal generation circuitry has at least a first input coupled to the data input of the first latch and a second input coupled to the data output of the second latch, and is configured to generate an output that is indicative, relative to the reference signal, of the phase error of a clock signal.

Abstract: A high-pass filter has a variable resistance which can be varied by a trimming signal and a programming signal. The variable resistance has a common resistance which is controlled by the trimming signal or the programming signal through a common control line.

Abstract: A method and apparatus for determining the center frequency of a bandpass filter. The center frequency of a bandpass filter is determined by applying a bias voltage to a bandpass filter circuit receiving a pair of differential input voltages and producing a pair of differential output voltages. The differential output voltages are modified to exhibit a notchband magnitude characteristic. A minimum value of the differential output voltages exhibiting the notchband characteristic over a predetermined range of frequencies is determined and corresponds to the center frequency of the bandpass filter.

Abstract: A method and apparatus for linearly adjusting the bandwidth of a high-order bandpass filter. A high-order bandpass filter is formed by cascading together two or more low-order bandpass filters. The bandwidths and center frequencies of each individual low-order bandpass filter is adjusted. The center frequency of some low-order bandpass filters are adjusted so as to achieve linear adjustment of the bandwidth of the high-order bandpass filter.