Systems and methods for programmable pulse density modulation (PDM) components enable backwards compatibility while maintaining reasonable tolerances. A system includes a programmable PDM device, a PDM master device and a bus communicably coupling the programmable PDM device to the PDM receiver. The PDM device may include an audio sensor, audio input circuitry, a delta-sigma converter and a PDM transmitter and receiver. The PDM transmitter and receiver may send out PDM data from the PDM device and receive programming data from the PDM Master device. The PDM device may further include register space controlled by the PDM master device, a buffer storing audio data for wakeup word systems that store audio data when the PDM receiver is powered down, a bus holder to hold the previous value on the bus if no device is driving it, and/or a clock multiplier to multiply the incoming clock by a factor.

Systems and methods for programmable pulse density modulation (PDM) components enable backwards compatibility while maintaining reasonable tolerances. A system includes a programmable PDM device, a PDM master device and a bus communicably coupling the programmable PDM device to the PDM receiver. The PDM device may include an audio sensor, audio input circuitry, a delta-sigma converter and a PDM transmitter and receiver. The PDM transmitter and receiver may send out PDM data from the PDM device and receive programming data from the PDM Master device. The PDM device may further include register space controlled by the PDM master device, a buffer storing audio data for wakeup word systems that store audio data when the PDM receiver is powered down, a bus holder to hold the previous value on the bus if no device is driving it, and/or a clock multiplier to multiply the incoming clock by a factor.

A duty cycle correction circuit includes a sawtooth wave generating unit, a voltage regulating unit, a differential comparator, a differential amplifier and low-pass filters. The sawtooth wave generating unit converts a narrow pulse signal into a sawtooth wave signal with a duty cycle of 50% which is input into the differential comparator. The voltage regulating unit regulates an input voltage value of a non-inverting input terminal of the differential comparator. The differential comparator compares a voltage difference between input signals of input terminals and outputs an output clock signal. The low-pass filters input DC components to the differential amplifier which amplifies the DC signals and output to the voltage regulating unit. The duty cycle correction circuit has a small chip occupying area to realize high integration of the chip, and the duty cycle of the output clock is accurately corrected to ensure the stability of the output clock frequency.

A duty cycle correction circuit includes a sawtooth wave generating unit, a voltage regulating unit, a differential comparator, a differential amplifier and low-pass filters. The sawtooth wave generating unit converts a narrow pulse signal into a sawtooth wave signal with a duty cycle of 50% which is input into the differential comparator. The voltage regulating unit regulates an input voltage value of a non-inverting input terminal of the differential comparator. The differential comparator compares a voltage difference between input signals of input terminals and outputs an output clock signal. The low-pass filters input DC components to the differential amplifier which amplifies the DC signals and output to the voltage regulating unit. The duty cycle correction circuit has a small chip occupying area to realize high integration of the chip, and the duty cycle of the output clock is accurately corrected to ensure the stability of the output clock frequency.

Analog calibration (ACAL) circuits supporting iterative measurement of an input signal from a measured circuit, and related methods are disclosed. The ACAL circuit includes a voltage reference generation circuit and a comparator circuit. The voltage reference generation circuit is configured to provide an input reference voltage. The comparator circuit is configured to compare the input reference voltage to an input circuit voltage of a measured circuit and generate a digital measurement signal based on the comparison. To provide for the ACAL circuit to more precisely measure the input circuit voltage, the voltage reference generation circuit is programmable and is configured to a generate the input reference voltage based on a programmed reference voltage selection. In this manner, the ACAL circuit can be used to measure the input circuit voltage in an iterative manner based on different programmed input reference voltages for a more precise measurement of the input circuit voltage.

Analog calibration (ACAL) circuits supporting iterative measurement of an input signal from a measured circuit, and related methods are disclosed. The ACAL circuit includes a voltage reference generation circuit and a comparator circuit. The voltage reference generation circuit is configured to provide an input reference voltage. The comparator circuit is configured to compare the input reference voltage to an input circuit voltage of a measured circuit and generate a digital measurement signal based on the comparison. To provide for the ACAL circuit to more precisely measure the input circuit voltage, the voltage reference generation circuit is programmable and is configured to a generate the input reference voltage based on a programmed reference voltage selection. In this manner, the ACAL circuit can be used to measure the input circuit voltage in an iterative manner based on different programmed input reference voltages for a more precise measurement of the input circuit voltage.

An apparatus for in-phase and quadrature phase (“IQ”) generation comprises a CMOS clock distributor for providing a clock input. A first IQ divider circuit is configured for receiving the clock input and dividing the clock input into in-phase and quadrature phase (IQ) output. A clock processing circuit is configured for processing the clock input. A second IQ divider circuit is configured for receiving the processed clock input and dividing the processed clock input into in-phase and quadrature phase (IQ) output. A multiplexer circuit is coupled to the first IQ divider circuit and the second IQ divider circuit for selecting the IQ output from the first IQ divider circuit or the second IQ divider circuit.

An apparatus for in-phase and quadrature phase (“IQ”) generation comprises a CMOS clock distributor for providing a clock input. A first IQ divider circuit is configured for receiving the clock input and dividing the clock input into in-phase and quadrature phase (IQ) output. A clock processing circuit is configured for processing the clock input. A second IQ divider circuit is configured for receiving the processed clock input and dividing the processed clock input into in-phase and quadrature phase (IQ) output. A multiplexer circuit is coupled to the first IQ divider circuit and the second IQ divider circuit for selecting the IQ output from the first IQ divider circuit or the second IQ divider circuit.

An example of an apparatus may include NAND memory and circuitry coupled to the NAND memory to provide duty cycle correction (DCC) for one or more write paths of the NAND memory. Other examples are disclosed and claimed.

An example of an apparatus may include NAND memory and circuitry coupled to the NAND memory to provide duty cycle correction (DCC) for one or more write paths of the NAND memory. Other examples are disclosed and claimed.