A frequency measurement apparatus includes: a measurement period setting circuit that sets a measurement period based on a reference clock signal; a first counter circuit that counts the number of pulses of the reference clock signal in a period based on an input signal during the measurement period; a second counter circuit that counts the number of pulses of the input signal during the measurement period; a first frequency calculation circuit that calculates a first frequency; a second frequency calculation circuit that calculates a second frequency; and a frequency selection circuit that selects the first frequency or the second frequency as a frequency of the input signal.

The present invention provides a fractional frequency divider, wherein the fractional frequency divider includes a plurality of registers, a control signal generator and a clock gating circuit. Regarding the plurality of registers, at least a portion of the registers are set to have values. The control signal generator is configured to generate a control signal based on an input clock signal and values in the at least a portion of the registers, wherein the control generator sequentially generates the control signal during each cycle of the input clock signal. The clock gating circuit is configured to refer to the control signal to mask or not mask the input clock signal to generate an output clock signal.

A control system includes a mirror controller generating horizontal and vertical mirror synchronization signals for a mirror based upon a mirror clock signal. Laser modulation circuitry generates horizontal and vertical laser synchronization signals as a function of first and second laser clock signals and generates control signals for a laser that emits a laser beam that impinges on the mirror. First synchronization circuitry receives the horizontal mirror synchronization signal and the horizontal laser synchronization signal, and modifies generation of the first laser clock signal to achieve alignment between the horizontal mirror synchronization signal and horizontal laser synchronization signal. Second synchronization circuitry receives the vertical mirror synchronization signal and the vertical laser synchronization signal, and modifies generation of the second laser clock signal to achieve alignment between the vertical mirror synchronization signal and vertical laser synchronization signal.

A disclosed apparatus for accomplishing such a task may include (1) a circuit board incorporated into a module designed for insertion into slots of computing devices, (2) at least one conductive contact disposed on the circuit board, (3) a counter circuit disposed on the circuit board and communicatively coupled to the conductive contact, wherein the counter circuit comprises (A) a signal-change detector that detects signal changes as the module is inserted into one of the slots of the computing devices and (B) a counter device that maintains a dynamic count indicative of a number of times that the module has been inserted into one of the slots of the computing devices based at least in part on the signal changes, (4) a battery electrically coupled to the counter circuit, wherein the battery powers the counter device prior to the insertion. Various other apparatuses, systems, and methods are also disclosed.

A disclosed apparatus for accomplishing such a task may include (1) a circuit board incorporated into a module designed for insertion into slots of computing devices, (2) at least one conductive contact disposed on the circuit board, (3) a counter circuit disposed on the circuit board and communicatively coupled to the conductive contact, wherein the counter circuit comprises (A) a signal-change detector that detects signal changes as the module is inserted into one of the slots of the computing devices and (B) a counter device that maintains a dynamic count indicative of a number of times that the module has been inserted into one of the slots of the computing devices based at least in part on the signal changes, (4) a battery electrically coupled to the counter circuit, wherein the battery powers the counter device prior to the insertion. Various other apparatuses, systems, and methods are also disclosed.

Systems, devices, and methods related to frequency converter arrangements are provided. For example, a frequency converter arrangement converts a first signal centered at a first frequency to a second signal centered at a second frequency different from the first frequency. The frequency converter arrangement includes local oscillator (LO) circuitry and in-phase, quadrature-phase (IQ) mixer circuitry coupled to the LO circuitry. The LO circuitry includes duty cycle correction circuitry to adjust a duty cycle of a pair of input clock signals. The duty cycle correction circuitry includes coarse tuning circuitry responsive to a digital calibration code, and analog tuning loop circuitry. The LO circuitry further includes quadrature divider circuitry coupled to an output of the duty cycle correction circuitry, where the quadrature divider circuitry generates an in-phase LO signal and a quadrature-phase LO signal from a pair of output clock signals at outputs of the duty cycle correction circuitry.

Systems, devices, and methods related to frequency converter arrangements are provided. For example, a frequency converter arrangement converts a first signal centered at a first frequency to a second signal centered at a second frequency different from the first frequency. The frequency converter arrangement includes local oscillator (LO) circuitry and in-phase, quadrature-phase (IQ) mixer circuitry coupled to the LO circuitry. The LO circuitry includes duty cycle correction circuitry to adjust a duty cycle of a pair of input clock signals. The duty cycle correction circuitry includes coarse tuning circuitry responsive to a digital calibration code, and analog tuning loop circuitry. The LO circuitry further includes quadrature divider circuitry coupled to an output of the duty cycle correction circuitry, where the quadrature divider circuitry generates an in-phase LO signal and a quadrature-phase LO signal from a pair of output clock signals at outputs of the duty cycle correction circuitry.

A fail-safe counter evaluator is provided to insure proper counting operations by fail-safe counters. The failsafe counter evaluator comprises a first microprocessor, a first counter, a second counter, a second microprocessor and a test channel. The first counter is configured as a counter in operation and disposed in the first microprocessor to receive externally generated count pulses. The second counter is disposed in the first microprocessor and configured to undergo a test. The test channel is configured to send an input test signal to the second counter based on test pulses from the second microprocessor. The first microprocessor and the second microprocessor are synchronized so that to coordinate a start and an end of the test. The second counter is evaluated after the test pulses have been sent to determine if the second counter is operating properly.

A sensing circuit in a device having a moving body in which a unit to be detected including first and second pattern units spaced apart from each other is formed includes an oscillation circuit unit including first and second oscillation circuits fixedly mounted on a substrate spaced apart from the unit to be detected, including, respectively, first and second sensing coils having first and second inductance values depending on areas of overlap between the first and second sensing coils and the first and second pattern units and outputting, respectively, first and second sensed oscillation signals based on the first and second inductance values; and a sensing circuit outputting an output signal having movement information of the moving body based on each period count value for each of the first and second sensed oscillation signals using a reference oscillation signal.

A sensing circuit in a device having a moving body in which a unit to be detected including first and second pattern units spaced apart from each other is formed includes an oscillation circuit unit including first and second oscillation circuits fixedly mounted on a substrate spaced apart from the unit to be detected, including, respectively, first and second sensing coils having first and second inductance values depending on areas of overlap between the first and second sensing coils and the first and second pattern units and outputting, respectively, first and second sensed oscillation signals based on the first and second inductance values; and a sensing circuit outputting an output signal having movement information of the moving body based on each period count value for each of the first and second sensed oscillation signals using a reference oscillation signal.