Abstract:
The invention provides a systematic error correction network coupled to a converter. The converter may display a systematic non-linearity error, and the systematic error correction network shapes a correction transform function that acts like counter distortion function for the non-linearity error. The systematic error correction network then scales the correction transform function according to a reference variable, where the magnitude of non-linearity error is related to the reference variable. The scaled correction transform function is then applied to the converter path in order to generate a corrected analog output signal.
Abstract:
An integrated circuit may include a plurality of circuit sub-systems that include at least one converter circuit operating in respective critical phases and non-critical phases of operation, a clock distribution circuit that has an input for an externally-supplied clock signal that is active during the non-critical phases and inactive during the critical phases, and a clock generator to generate an internal clock signal to the converter circuit that is active when the external-supplied clock signal is inactive.
Abstract:
An amplifier system can include a feedback amplifier circuit having an amplifier, a feedback capacitor connected between an input terminal and an output terminal of the amplifier by at least one first switch, and a reset capacitor connected across the feedback capacitor by at least one second switch and between a pair of reference voltages by at least one third switch. During an input-signal processing phase of operation, a control circuit may close the at least one first switch and open the at least one second switch to electrically connect the feedback capacitor between the input and output terminals to engage feedback processing by the feedback amplifier circuit, and close the third switch to electrically connect the reset capacitor between the first and second voltages to charge the reset capacitor to a selectable voltage difference. During a reset phase of operation, the control circuit may open the at least one third switch, close the at least one second switch and open the at least one first switch to electrically connect the reset capacitor across the feedback capacitor to reset the feedback capacitor using the reset capacitor. The amplifier system can optionally include a plurality of the feedback amplifier circuits.
Abstract:
An asynchronous digital sample rate converter includes a random access memory for storing input data values and a read only memory for storing a reduced set of interpolation filter coefficients. Input data is written to the random access memory at the input sample rate. Output samples are provided from a multiply/accumulate engine which given a stream of input data and filter coefficients produces an output sample upon request at the output frequency. The initial address for reading input data from the random access memory, and the addresses for coefficients from the read only memory are provided by an auto-centering scheme which is a first order closed loop system with a digital integrator fed by an approximation of the input to output sample rate ratio. This auto-centering scheme may include a feed forward low pass filter to cancel steady state error, and an interpolated write address to reduce noise. A circuit determining the output to input sample rate ratios can also be provided to scale coefficient addresses and resulting output samples to allow for decimation. This circuit includes a form of digital hysteresis to eliminate noise. The ROM coefficients are reduced by relying on the symmetry of the impulse response of the interpolation filter and by utilizing a variable step size forward and backward linear interpolation.
Abstract:
An asynchronous digital sample rate converter includes a random access memory for storing input data values and a read only memory for storing a reduced set of interpolation filter coefficients. Input data is written to the random access memory at the input sample rate. Output samples are provided from a multiply/accumulate engine which given a stream of input data and filter coefficients produces an output sample upon request at the output frequency. The initial address for reading input data from the random access memory, and the addresses for coefficients from the read only memory are provided by an auto-centering scheme which is a first order closed loop system with a digital integrator fed by an approximation of the input to output sample rate ratio. This auto-centering scheme may include a feed forward low pass filter to cancel steady state error, and an interpolated write address to reduce noise. A circuit determining the output to input sample rate ratios can also be provided to scale coefficient addresses and resulting output samples to allow for decimation. This circuit includes a form of digital hysteresis to eliminate noise. The ROM coefficients are reduced by relying on the symmetry of the impulse response of the interpolation filter and by utilizing a variable step size forward and backward linear interpolation.
Abstract:
An accurate, low noise conditionally resetting integrator circuit in an analog to digital system samples, with an analog to digital converter, the output of an integrating circuit a number of times during a measuring period; isolates the input for the integrating circuit during sample event; generates a reset signal in response to the integrating circuit output reaching a predetermined level; and resets the feedback capacitor of the integrating circuit by isolating it from the amplifier circuit of the integrating circuit and connecting it to a reference source during a sample event.
Abstract:
A calibratable analog-to-digital converter system with a split analog-to-digital converter architecture including N Analog-to-Digital Converters (ADCs) each configured to convert the same analog input signal into a digital signal. Calibration logic is responsive to the digital signals output by the N ADCs and is configured to calibrate each of the ADCs based on the digital signals output by each ADC.
Abstract:
A constant current supply system for a variable resistance load includes first and second output terminals for applying a predetermined current to a variable resistance load; a constant current circuit connected to the second output terminal for providing the predetermined current to the load; a voltage supply connected to the first terminal for providing a voltage across the terminal and constant current circuit; and a voltage supply control circuit for monitoring the voltage at the second terminal across the constant current circuit and adjusting the voltage supply to maintain the second terminal at a preselected voltage for maintaining the predetermined current to the variable resistance load.
Abstract:
An asynchronous digital sample rate converter includes a random access memory for storing input data values and a read only memory for storing a reduced set of interpolation filter coefficients. Input data is written to the random access memory at the input sample rate. Output samples are provided from a multiply/accumulate engine which given a stream of input data and filter coefficients produces an output sample upon request at the output frequency. The initial address for reading input data from the random access memory, and the addresses for coefficients from the read only memory are provided by an auto-centering scheme which is a first order closed loop system with a digital integrator fed by an approximation of the input to output sample rate ratio. This auto-centering scheme may include a feed forward low pass filter to cancel steady state error, and an interpolated write address to reduce noise. A circuit determining the output to input sample rate ratios can also be provided to scale coefficient addresses and resulting output samples to allow for decimation. This circuit includes a form of digital hysteresis to eliminate noise. The ROM coefficients are reduced by relying on the symmetry of the impulse response of the interpolation filter and by utilizing a variable step size forward and backward linear interpolation.
Abstract:
A semiconductor device formed on a substrate includes a first diode junction formation, a second diode junction formation, and at least one through-silicon-via (TSV), in which a cathode and an anode of the first diode are cross-connected to an anode and cathode of the second diode through the at least one TSV for achieving electrical robustness in through-silicon-via based integrated circuits, including photosensitive devices and circuits for signal processing applications.