Abstract: A hysteretic converter includes an inductor coupled between a source of voltage and a switch node. A low side switch is coupled between the switch node and a reference voltage. A high side switch is coupled between the switch node and the output of the converter. A driver controls the low side and high side switches, wherein the low side switch is turned on until the input current rises to a predetermined set point, the predetermined setpoint can be adapted to input current from the source of voltage.

Abstract: A maximum power point tracking circuit for an energy harvester device, the tracking circuit requiring nanoampere current in a standby mode, includes a maximum power point circuits utilizing a predetermined fraction of the open circuit input voltage to determine the maximum power point for energy harvester device. A circuit determines the predetermined fraction of the open circuit voltage of the energy harvester device.

Abstract: Systems and methods for analog to digital conversion charge storage device measurement are presented. In multi-cell charge storage device monitoring systems, accurate measurement of cell voltages is used for protection of the multi-cell device. The disclosed cell referenced solution converts the cell voltage to a digital representation referenced at the cell voltage. The digital representation referenced to the cell voltage is then level shifted to a ground referenced signal suitable for digital post processing. This processing may be used for fault detection of over-voltage, under-voltage, open cell, and similar fault conditions and cell capacity measurements. An example embodiment implements a sigma delta modulator to perform the signal transformation from analog to digital. The disclosed systems and methods may be differential and stackable for multiple cells.

Abstract: Systems and methods for analog to digital conversion charge storage device measurement are presented. In multi-cell charge storage device monitoring systems, accurate measurement of cell voltages is used for protection of the multi-cell device. The disclosed cell referenced solution converts the cell voltage to a digital representation referenced at the cell voltage. The digital representation referenced to the cell voltage is then level shifted to a ground referenced signal suitable for digital post processing. This processing may be used for fault detection of over-voltage, under-voltage, open cell, and similar fault conditions and cell capacity measurements. An example embodiment implements a sigma delta modulator to perform the signal transformation from analog to digital. The disclosed systems and methods may be differential and stackable for multiple cells.

Abstract: Distortion discrimination circuitry for digital radio receivers and corresponding methods are disclosed that accurately and efficiently discriminate distortion events, including impulse noise and multipath distortion events, to improve the quality of audio output signals. The distortion discrimination circuitry monitors and analyzes the demodulator output to determine when a distortion event has occurred and provides an appropriate indication signal for use by other circuitry within the radio receiver. More particularly, the distortion discrimination circuitry includes impulse noise circuitry that looks for high frequency noise in both the magnitude and multiplexed outputs of the demodulator to determine the occurrence of impulse noise distortion events.

Abstract: Oscillator circuitry on an integrated circuit automatically detects the presence or absence of an external resistor which is used to bias and set the frequency of an internal resistor-capacitor (RC) oscillator. If the resistor is present, the RC oscillator begins to oscillate to generate an oscillator clock. The presence of the oscillator clock is detected, and the RC oscillator continues to generate the oscillator clock. If the resistor is not present, the RC oscillator does not begin to oscillate. The absence of the oscillator clock is detected, and the oscillator circuitry automatically re-configures itself to generate the oscillator clock from an internal crystal oscillator circuit employing an external crystal.

Abstract: Oscillator circuitry on an integrated circuit automatically detects the presence or absence of an external resistor which is used to bias and set the frequency of an internal resistor-capacitor (RC) oscillator. If the resistor is present, the RC oscillator begins to oscillate to generate an oscillator clock. The presence of the oscillator clock is detected, and the RC oscillator continues to generate the oscillator clock. If the resistor is not present, the RC oscillator does not begin to oscillate. The absence of the oscillator clock is detected, and the oscillator circuitry automatically re-configures itself to generate the oscillator clock from an internal crystal oscillator circuit employing an external crystal.

Abstract: Quadrature sampling architecture and method are disclosed for analog-to-digital converters that provide improved digital output signals over prior quadrature mixing implementations. Sampling circuitry according to the present invention samples an input signal with a first and second sampling signals to produce real and imaginary sampled output signals. The first sampling signal, which is associated with the real sampled output signal, is delayed by one-fourth cycle with respect to the second sampling signal, which is associated with the imaginary sampled output signal. This one-fourth cycle sampling signal difference allows for simplified construction of the sampling circuitry. In addition, filter circuitry according to the present invention processes the real and imaginary digital data output signals so that the imaginary digital data output signal is advanced by one-fourth cycle with respect to the real digital data output signal.

Abstract: Station scan circuitry for a radio-frequency receiver and corresponding methods are disclosed that efficiently determine the presence of a station on available channels. The station scan circuitry includes circuitry that determines if the signal power on a given channel exceeds a threshold value. Additional circuitry compares the channel signal strength and the adjacent channel signal to determine if a ratio of the two exceeds a threshold level. If both the signal power and the signal strength ratio are sufficient, the station scan circuitry indicates that a station has been found. To make the signal strength comparison, the station scan circuitry includes circuitry for determining a post-filter signal strength and a pre-filter signal strength for the received signal.