An interpolator includes a first delay circuit, a second delay circuit, and a tunable delay circuit. The first delay circuit delays a first input signal for a fixed delay time, so as generate a first output signal. The second delay circuit delays a second input signal for the fixed delay time, so as to generate a second output signal. The tunable delay circuit delays the first input signal for a tunable delay time, so as to generate an output interpolation signal. The tunable delay time is determined according to the first output signal, the second output signal, and the output interpolation signal.

Embodiments include apparatuses, methods, and systems for jitter equalization and phase error detection. In embodiments, a communication circuit may include a data path to pass a data signal and a clock path to pass a clock signal. A jitter equalizer may be coupled with the data path and/or clock path to provide a programmable delay to the data signal and/or clock signal, respectively. The delay may be determined by a training process in which a supply voltage may be modulated by a modulation frequency. The delay may be dependent on a value of the supply voltage, such as a voltage level and/or jitter frequency component of the supply voltage. A phase error detector is also described that may be used with the communication circuit and/or other embodiments.

A phase angle can be measured between an analog signal and a reference signal by converting the analog signal to digital samples in a residue number system (RNS) analog-to-digital converter (ADC), based on a RNS scheme. The phase angle can be measured directly from the RNS values output by the RNS ADC, or the RNS values can be converted to a binary scheme, such as straight binary, offset binary or two's complement, before calculating the phase angle measurement.

Technologies are provided for adaptive control of bias settings in a digital microphone. In some embodiments, a device includes a first component that provides data indicative of a clock frequency of operation in a functional mode of a digital microphone. The clock frequency clocks one or more microphone components having switching activity. The device also can include a second component that determines, using the clock frequency, an amount of bias current to supply to at least a first microphone component of the one or more microphone components. The device can further include a memory device that retains control parameters that include at least one of a first subset of parameters defining a relationship between current and frequency and a second subset of parameters defining a quantization of the relationship. The quantization including multiple bias current levels for respective frequency intervals.

Technologies are provided for adaptive control of bias settings in a digital microphone. In some embodiments, a device includes a first component that provides data indicative of a clock frequency of operation in a functional mode of a digital microphone. The clock frequency clocks one or more microphone components having switching activity. The device also can include a second component that determines, using the clock frequency, an amount of bias current to supply to at least a first microphone component of the one or more microphone components. The device can further include a memory device that retains control parameters that include at least one of a first subset of parameters defining a relationship between current and frequency and a second subset of parameters defining a quantization of the relationship. The quantization including multiple bias current levels for respective frequency intervals.

A fast phase frequency includes two fast pulsed-latches, a NAND gate, and an adjustable delay circuit, where the fast pulsed-latches include a pulse generating circuit, a reset circuit, and an output latch circuit. The pulse generating circuit is configured to generate a power supply pulse signal when a rising edge of the clock signal arrives, the power supply pulse signal causing the input of the output latch circuit to be a low level. The output latch circuit is configured to maintain its current output state when the clock signal or the reset signal is invalid, and the reset circuit is configured to set the input of the output latch circuit to be a high level. By using fast pulsed-latches with clock and reset control, the fast phase frequency detector shortens the reset loop delay and increases the maximum operating frequency of the phase frequency detector.

A time detection circuit and a time detection method are provided. The time detection circuit includes an input signal processor and a time signal amplifier. The input signal processor receives a first input signal and a second input signal, calculates a time difference value between the first input signal and the second input signal, adjusts the time difference value by comparing the time difference value with a set reference value, and provides the adjusted time difference value. The time signal amplifier receives the adjusted time difference value, and amplifies the adjusted time difference value to generate an amplified time signal. The time signal amplifier operates in a linear operation region between a first time value and a second time value, and the set reference value is set according to the first time value and the second time value.

Disclosed a fast phase frequency detector, comprising: two fast pulsed-latches, a NAND gate and an adjustable delay circuit. The fast pulsed-latches comprises: a pulse generating circuit, a reset circuit, and an output latch circuit; the pulse generating circuit is configured to generate a power supply pulse signal when a rising edge of the clock signal arrives, the power supply pulse signal causing the input of the output latch circuit to be a low level; the output latch circuit is configured to maintain its current output state when the clock signal or the reset signal is invalid; the reset circuit is configured to set the input of the output latch circuit to be a high level. By using fast pulsed-latches with clock and reset control, the fast phase frequency detector of the present application shortens the reset loop delay and increases the maximum operating frequency of the phase frequency detector.

An interpolator includes a first delay circuit, a second delay circuit, and a tunable delay circuit. The first delay circuit delays a first input signal for a fixed delay time, so as generate a first output signal. The second delay circuit delays a second input signal for the fixed delay time, so as to generate a second output signal. The tunable delay circuit delays the first input signal for a tunable delay time, so as to generate an output interpolation signal. The tunable delay time is determined according to the first output signal, the second output signal, and the output interpolation signal.

A temperature-compensated resonant MEMS device comprises a first and second oscillator circuits comprising a first and second resonant MEMS devices and providing a first and second oscillator outputs. One of the resonant MEMS devices is a temperature reference for the other. A level-sensitive mixer circuit has first and second inputs coupled to the first and second oscillator outputs and has a mixer output to provide a signal responsive to a level of the first and second oscillator outputs. The mixer output comprises sum and difference frequency components of the first and second oscillator outputs. A low-pass filter is coupled to the mixer output to attenuate the sum frequency component of the mixer output. An output coupled to an output of said low-pass filter provides a signal responsive to the difference frequency component.