Abstract:
One feature pertains to the synchronization of a serial time-division-multiplexed bus interconnecting an audio processing subsystem (i.e. a local node) with an audio coder-decoder (CODEC) subsystem (i.e. a remote node.) Control signals are transmitted along a bidirectional transmission line of the bus from the audio processing subsystem to the audio CODEC subsystem. The audio processing subsystem tracks an internal state machine phase count as the control signals are transmitted. The audio CODEC subsystem also tracks an internal state machine phase count as the signals are received. Transmission of control signals by the audio processing subsystem is periodically paused or suspended for a fixed interval of time based on the phase count to allow the audio CODEC subsystem to send a synchronization indicator signal back to the audio processing subsystem, which the audio processing subsystem uses to verify synchronization. This may be performed, for example, once every one hundred-twenty phase counts.
Abstract:
A serial data receiver may include an edge detector and a digital integrator. The edge detector may be configured to provide one or more edge detection signals defining an edge detection indication in response to a comparison between two successive samples of a receiver input signal. The edge detection indication may represent a detected negative edge, a detected positive edge, or no detected edge. The digital integrator may be configured to provide a receiver output signal in response to integration of the one or more edge detection signals.
Abstract:
A device includes a snapback clamp circuit configured to clamp a supply voltage in response to the supply voltage exceeding a trigger voltage level. In at least one embodiment, the snapback clamp circuit includes a clamp transistor and a programmable resistance portion that is responsive to a control signal to calibrate the trigger voltage level. Alternatively or in addition, the snapback clamp circuit may include a programmable bias device configured to calibrate the trigger voltage level by biasing a gate terminal of the clamp transistor. In another particular embodiment, a method of calibrating a snapback clamp circuit is disclosed. In another particular embodiment, a method of operating an integrated circuit is disclosed.
Abstract:
Methods, systems, and circuits for providing low-noise amplification with input common mode voltage following are disclosed. A circuit includes: an amplifier configured to receive a voltage input having an input common mode voltage and configured to generate a differential voltage output having an output common mode voltage; a feedback circuit in communication with the amplifier, the feedback circuit configured to receive the input common mode voltage and the differential voltage output and to generate a feedback voltage in response to the input common mode voltage and the differential voltage output; and an adjustable current source of the amplifier configured to receive the feedback voltage and to adjust a tail current of the amplifier in response to the feedback voltage.
Abstract:
A device includes a snapback clamp circuit configured to clamp a supply voltage in response to the supply voltage exceeding a trigger voltage level. In at least one embodiment, the snapback clamp circuit includes a clamp transistor and a programmable resistance portion that is responsive to a control signal to calibrate the trigger voltage level. Alternatively or in addition, the snapback clamp circuit may include a programmable bias device configured to calibrate the trigger voltage level by biasing a gate terminal of the clamp transistor. In another particular embodiment, a method of calibrating a snapback clamp circuit is disclosed. In another particular embodiment, a method of operating an integrated circuit is disclosed.
Abstract:
A serial data receiver may include an edge detector and a digital integrator. The edge detector may be configured to provide one or more edge detection signals defining an edge detection indication in response to a comparison between two successive samples of a receiver input signal. The edge detection indication may represent a detected negative edge, a detected positive edge, or no detected edge. The digital integrator may be configured to provide a receiver output signal in response to integration of the one or more edge detection signals.
Abstract:
An apparatus includes voltage-to-current conversion circuitry comprising a first voltage-to-current converter and a second voltage-to-current converter. The apparatus also includes a capacitor coupled to the first voltage-to-current converter and to the second voltage-to-current converter.
Abstract:
One feature pertains to the synchronization of a serial time-division-multiplexed bus interconnecting an audio processing subsystem (i.e. a local node) with an audio coder-decoder (CODEC) subsystem (i.e. a remote node.) Control signals are transmitted along a bidirectional transmission line of the bus from the audio processing subsystem to the audio CODEC subsystem. The audio processing subsystem tracks an internal state machine phase count as the control signals are transmitted. The audio CODEC subsystem also tracks an internal state machine phase count as the signals are received. Transmission of control signals by the audio processing subsystem is periodically paused or suspended for a fixed interval of time based on the phase count to allow the audio CODEC subsystem to send a synchronization indicator signal back to the audio processing subsystem, which the audio processing subsystem uses to verify synchronization. This may be performed, for example, once every one hundred-twenty phase counts.
Abstract:
A switching amplifier includes a compensation circuit to compensate for DC offset in the amplifier, to enhance operation of the switching amplifier. The compensation circuit may comprise a SAR ADC, where the DAC element can be used to provide a compensation voltage. The switching amplifier may further include a PWM modulator configured to avoid cross-talk to further enhance operation of the switching amplifier.
Abstract:
A switching amplifier includes a compensation circuit to compensate for DC offset in the amplifier, to enhance operation of the switching amplifier. The compensation circuit may comprise a SAR ADC, where the DAC element can be used to provide a compensation voltage. The switching amplifier may further include a PWM modulator configured to avoid cross-talk to further enhance operation of the switching amplifier.