A resolver converter includes a tracking loop circuit that calculates an angle θ from a resolver output signal, a control and diagnosis circuit that controls the tracking loop circuit and diagnoses based on the resolver output signal, wherein the control and diagnosis circuit, by operating the tracking loop circuit as a direct digital synthesizer (DDS), synchronously detects a noise signal superimposed on the resolver output signal.

Processing a resolver signal by a microcontroller includes generating, by a carrier signal generator, a carrier signal for output to a resolver; receiving modulated carrier signals from a resolver via hardware that is external to the microcontroller; integrating, by an integrator, respective integrator input signals which are based on the modulated carrier signals, to generate respective envelope signals, wherein a start of an integration window of the integrator is set with respect to a start of the carrier signal; and determining an angular position sensed by the resolver based on the envelope signals.

A solid-state imaging device includes a first converter which converts an analog signal representing a pixel value to an upper bit of a digital signal, and a second converter which converts the analog signal to a lower bit of the digital signal. The second converter includes a first latch circuit which latches, as phase information, a plurality of clock signals having different phases upon conversion to the upper bit in the first converter, a conversion circuit which generates the lower bit of the digital signal by converting the phase information to a binary value, and an adder, and a second latch circuit which latches an addition result of the adder. The adder adds the binary value converted by the conversion circuit and a value latched by the second latch circuit.

A resolver signal processing circuit for amplifying two phase signals output from a resolver includes first and second amplifier circuits configured to adjust an input in-phase voltage range to output an intended voltage even when a short-circuit arises in the resolver. The resolver signal processing circuit further includes first and second short-circuit detection circuits configured to detect the short-circuit arising in the resolver and short-circuits in first and second signal input paths from the resolver to the first and the second amplifier circuits, respectively, and first and second voltage adjusting units configured to adjust input in-phase voltage ranges of the first and second amplifier circuits when the first and second short-circuit detection circuits detect short-circuits, respectively. The first and second amplifier circuits are configured to adjust the input in-phase voltage ranges, respectively.

An A/D conversion circuit converts an analog signal into numerical data. The A/D conversion circuit includes: a pulse delay circuit that includes an odd number of delay units connected in series, and inverting and delaying a pulse signal, and that changes the numeral number of the delay units which the pulse signal passes through in accordance with a value of the analog signal; latch circuits that synchronize the pulse signal with sampling clocks, and latch the pulse signal; encoders that set a position of the pulse signal to the numerical data by circulating encode values periodically set in order from an initial value to a final value to synchronously sample the encode values; subtractors that calculate each of differences between a previous value and a current value; and an adder that adds subtraction results. The encode values are set to be shifted between at least two encoders.

A solid-state imaging device includes a first converter which converts an analog signal representing a pixel value to an upper bit of a digital signal, and a second converter which converts the analog signal to a lower bit of the digital signal. The second converter includes a first latch circuit which latches, as phase information, a plurality of clock signals having different phases upon conversion to the upper bit in the first converter, a conversion circuit which generates the lower bit of the digital signal by converting the phase information to a binary value, and an adder, and a second latch circuit which latches an addition result of the adder. The adder adds the binary value converted by the conversion circuit and a value latched by the second latch circuit.

An A/D conversion circuit converts an analog signal into numerical data. The A/D conversion circuit includes: a pulse delay circuit that includes an odd number of delay units connected in series, and inverting and delaying a pulse signal, and that changes the numeral number of the delay units which the pulse signal passes through in accordance with a value of the analog signal; latch circuits that synchronize the pulse signal with sampling clocks, and latch the pulse signal; encoders that set a position of the pulse signal to the numerical data by circulating encode values periodically set in order from an initial value to a final value to synchronously sample the encode values; subtractors that calculate each of differences between a previous value and a current value; and an adder that adds subtraction results. The encode values are set to be shifted between at least two encoders.

A resolver converter includes a tracking loop circuit that calculates an angle from a resolver output signal, a control and diagnosis circuit that controls the tracking loop circuit and diagnoses based on the resolver output signal, wherein the control and diagnosis circuit, by operating the tracking loop circuit as a direct digital synthesizer (DDS), synchronously detects a noise signal superimposed on the resolver output signal.

In a semiconductor device, a sine wave signal is input to a first input part and a cosine wave signal is input to a second input part. A multiplexer alternately selects one of the sine wave signal and the cosine wave signal. An analog to digital converter converts the output signal of the multiplexer into a digital value. A switching circuit is coupled between at least one of the first and second input parts and the multiplexer. The switching circuit is configured to be able to invert the input sine wave signal or the input cosine wave signal, in order to reduce the angle detection error due to the non-linearity error of the A/D converter.

A comparator includes a resolver controlled by a resolver clock signal and a differential amplifier controlled by a sampling clock signal. The resolver clock signal and the sampling clock signal are such that amplification at the differential amplifier during the reset phase of the resolver clock signal and the reset phase of the sampling clock signal begins during the resolving phase of the resolver.