Abstract:
A voltage level detector is provided. The voltage level detector includes a comparator and a threshold level changer. The comparator compares a voltage level of an increasing or decreasing input signal with a threshold level, and generates and outputs a voltage level detection signal indicating that the input signal has reached the threshold level. The threshold level changer changes the threshold level of the comparator based on the voltage level detection signal by increasing the threshold level when the input signal is monotonically increasing and decreasing the threshold level when the input signal is monotonically decreasing.
Abstract:
A phase detector is provided. The phase detector includes a signal selector, a bias level generator, and a phase information detector. The signal selector selects, as a selected sensor signal, one of a plurality of sensor signals each having a signal level corresponding to a phase of a rotor. The bias level generator divides a signal level difference between a pair of sensor signals, including the selected sensor signal and other sensor signal of the plurality of sensor signals other than the selected sensor signal, at a first ratio, to generate a first bias level. The phase information detector generates a threshold level corresponding to the phase of the rotor based on the first bias level, and detects the signal level of the selected sensor signal reaching the threshold level.
Abstract:
A voltage level detector is provided. The voltage level detector includes a comparator and a threshold level changer. The comparator compares a voltage level of an increasing or decreasing input signal with a threshold level, and generates and outputs a voltage level detection signal indicating that the input signal has reached the threshold level. The threshold level changer changes the threshold level of the comparator based on the voltage level detection signal by increasing the threshold level when the input signal is monotonically increasing and decreasing the threshold level when the input signal is monotonically decreasing.
Abstract:
A motor drive controller to control a motor via multiple sensors includes a first phase detector to compare respective differential pairs of the sensor signals from the same sensor to detect phases of the rotor, and output a first phase information signal; a second phase detector to compare a respective one of the multiple sensor signals with another sensor signal from the different sensor to detect the phases and output a second phase information signal; a phase divider to divide the phases, detected by the first and second phase detectors, into multiple predetermined phase intervals; a signal selector to select one of the multiple sensor signals in the multiple predetermined phase intervals; and a third phase detector to detect whether the signal selected by the signal selector reaches a predetermined threshold level corresponding to a predetermined phase of the rotor, and output a third phase information signal.
Abstract:
A motor drive controller to drive a motor, based on multiple sensors that generates multiple sensor signals corresponding to different positions of the rotor; including a first phase detector to compare a respective one of the multiple sensor signals with a paired sensor signal from the same sensor to detect phases of the rotor, and output a first phase information signal representing a first detected phase; a phase divider to divide the phases, detected by the first phase detector into multiple predetermined phase intervals; a signal selector to select one of the respective multiple sensor signals from the multiple sensors in the multiple predetermined phase interval; and a second phase detector to detect whether the signal selected by the signal selector reaches a predetermined threshold level corresponding to a predetermined phase of the rotor, and output a second phase information signal representing a second detected phase.
Abstract:
Disclosed is a receiving device that includes a differential input circuit having an inverting input terminal and a non-inverting input terminal to which the differential signal is input; an abnormality detection circuit that detects an abnormality in a wiring connected to the inverting input terminal and the non-inverting input terminal; and a control circuit that sets an output signal of the receiving device in a predetermined status when the abnormality is detected. The abnormality detection circuit detects the abnormality if a status, in which a potential difference between a voltage of the inverting input terminal and a voltage of the non-inverting input terminal is less than a minimum potential difference in a predetermined range of the potential difference between the voltage of the inverting input terminal and the voltage of the non-inverting input terminal, continues for a predetermined time or more.
Abstract:
A driving circuit is disclosed that has low power consumption and supplies a current to a load. The driving circuit includes a constant current circuit section to generate and output a predetermined constant current, a current mirror circuit section to generate a current proportional to an input current supplied from the constant current circuit section and supply the current to the load, and a constant voltage supplying circuit section to generate a constant voltage and supply the constant voltage to a series circuit of the load and an output transistor of the current mirror circuit. The constant voltage supplying circuit section gene-rates the constant voltage so that an output voltage of the current mirror circuit section equals an input voltage of the current mirror circuit section.
Abstract:
A laser diode drive includes a first photo diode connection terminal to connect a first photo diode that detects light emission amounts of multiple laser diodes, multiple second photo diode connection terminals to connect multiple second photo diodes that detect light emission amounts of the respective multiple laser diodes, multiple APC controllers to control the light emission amounts of the multiple laser diodes based on monitor currents from the first photo diode or the second photo diodes, multiple switches to connect and disconnect the respective APC controllers with a monitor current path formed between the first photo diode connection terminal and the multiple APC controllers, and a detector to detect whether or not the first photo diode is connected to the first photo diode connection terminal and cause all of the switches to disconnect when the first photo diode is not connected to the first photo diode connection terminal.
Abstract:
A semiconductor laser driver to execute automatic power control (APC) for multiple semiconductor lasers based on a common APC output from an image controller. The semiconductor laser driver includes a drive circuit to generate an individual APC signal to execute APC for each semiconductor laser based on the common APC signal.
Abstract:
A disclosed multi-beam laser power control circuit includes a light receiving element receiving power output from semiconductor lasers to control output power of a semiconductor laser array having plural semiconductor lasers, automatic power control circuits (APC circuits) controlling emission power output from semiconductor lasers based on received corresponding automatic power control execution signals so as to be set to predetermined emission power based on output from the light receiving element, and APC execution signal input terminals inputting the corresponding automatic power control execution signals, wherein, when plural APC execution signals input to the corresponding APC execution signal input terminals are overlapped, the automatic power control circuits (APC circuits) to be preferentially operated is determined based on input timings of the APC execution signals and operated.