Abstract: In a communication system, a control unit and driver units are connected in a daisy chain; each unit includes a corresponding insulated communication circuit, respectively. The control unit measures a communication delay time between the control unit and each driver unit from a response time to transmission of a pulse signal performed to each driver unit during a measurement period. Then, based on each communication delay time, the control unit transmits a shift time to each driver unit for equalizing the timing of signals output by the driver units. When each driver unit receives, from the control unit, an instruction instructing each driver unit to output a signal, each driver unit outputs the signal when the shift time has elapsed.

Abstract: A differential communication circuit is connected to a communication line formed of a positive communication line and a negative communication line for differential communication. The differential communication circuit includes: a series circuit that includes a resistor element and a connection switch. The resistor element is connected between the positive and negative communication lines when the connection switch is turned on. The circuit also includes a transmission unit that is configured to output a differential signal to the communication line and a controller that is configured to change impedance of the communication line by turning on the connection switch in a period during which the transmission unit does not output the differential signal.

Abstract: An insulated communication system includes a communication controller that sets communication data to a communication symbol through a numeral system and executes insulated communication through an insulator by adopting the communication symbol. The numeral system includes multiple states having a positive state, a negative state and a zero state. The positive state is represented by at least one positive integer, and the negative state is represented by at least one negative integer. The zero state is represented by zero being a level without generating current consumption. An absolute value of the at least one positive integer and an absolute value of the at least one negative integer are identical to each other. The communication controller sets an initial section of the communication data in the communication symbol to the positive state or the negative state, and sets a following section of the communication data to one of the multiple states.

Abstract: A differential transmission circuit for a communication device performs bidirectional communication via a differential transmission line. The differential transmission circuit include: output transistors that are turned on and off according to a drive signal during a transmission period; a signal generation unit that generates and outputs the drive signal; short-circuit transistors connected between gates and drains of the output transistors; and a cut off unit that cuts off a supply path of the drive signal between the signal generation unit and the gates of the output transistors. The cut off unit cuts off the supply path of the drive signal during a reception period in which a reception operation is performed by the communication device.

Abstract: In a pulse edge detection circuit, a measurement circuit has a comparator provided therein which compares a voltage with a reference voltage and outputs a pulse signal. An RSFF puts a signal in a high level at a timing at which detecting a rise edge due to a change of the pulse signal to the high level. In such manner, a set signal of an RSFF becomes inactive and a reset signal of the RSFF becomes active, and a fall edge of the pulse signal becomes detectable. When a fall edge is generated due to a change of the pulse signal from the high level to the low level, the set signal of the RSFF becomes active, and a signal becomes high level.

Abstract: A differential communication circuit is connected to a communication line formed of a positive communication line and a negative communication line for differential communication. The differential communication circuit includes: a series circuit that includes a resistor element and a connection switch. The resistor element is connected between the positive and negative communication lines when the connection switch is turned on. The circuit also includes a transmission unit that is configured to output a differential signal to the communication line and a controller that is configured to change impedance of the communication line by turning on the connection switch in a period during which the transmission unit does not output the differential signal.

Abstract: In a communication system, a control unit and driver units are connected in a daisy chain; each unit includes a corresponding insulated communication circuit, respectively. The control unit measures a communication delay time between the control unit and each driver unit from a response time to transmission of a pulse signal performed to each driver unit during a measurement period. Then, based on each communication delay time, the control unit transmits a shift time to each driver unit for equalizing the timing of signals output by the driver units. When each driver unit receives, from the control unit, an instruction instructing each driver unit to output a signal, each driver unit outputs the signal when the shift time has elapsed.

Abstract: A differential communication driver circuit includes a drive unit that drives differential signal lines connected via capacitors by a source current and a sink current. When a noise detection unit detects that in-phase noise is applied to the differential signal lines, a drive assisting unit maintains an amplitude of a differential signal output to the differential signal lines by increasing a current drive capability of the sink current.

Abstract: A rotation angle detection device for detecting a rotation angle of a rotating body includes a magnet disposed to rotate together with the rotating body, a magnetic portion provided in a ring shape radially outward of the magnet, a plurality of gaps being formed in the magnetic portion at a plurality of locations along a circumferential direction, and a magnetic detection unit arranged in a particular gap of the plurality of gaps. The magnetic detection unit is located at a detection position, a width of the particular gap in the tangential direction at the detection position is defined as a detection position gap width, a width of the particular gap in the tangential direction at a position radially outward of the detection position is defined as a tangential width, and the tangential width is narrower than the detection position gap width.

Abstract: An output terminal of a signal output device is connected through a branch path to a voltage dividing point in a main path, and transmits an output signal based on a voltage of the voltage dividing point to an outside. A signal generation circuit adjusts the voltage of the voltage dividing point and generates the output signal. A short circuit detection circuit detects a short circuit between the output terminal and another terminal when a current flowing in the branch path is greater than a predetermined short circuit detection threshold. A switching circuit switches a current carrying capacity or a configuration of the signal generation circuit to limit a short circuit current flowing in the branch path when the short circuit is detected. The short circuit current is set to a value equal to or greater than the short circuit detection threshold and less than a current upper limit value.

Abstract: A communication apparatus operates with a supply voltage of a power and transmits a sensor value with a digital communication method using consecutive frames. In the communication apparatus, a data source unit is configured to generate a frame using a data of a sensor value processed by a signal processing unit. A switching unit is configured to perform a signal switching to permit a transmission circuit to perform a re-transmission of re-transmitting a signal including the sensor value stored in a memory in response to a restoration of the power after an instantaneous power interruption. A frame monitoring unit is configured to monitor a status of a frame transmission and determine a frame at the occurrence of the instantaneous power interruption. The sensor value to be re-transmitted is determined based on information of the frame determined by the frame monitoring unit at the occurrence of the instantaneous power interruption.

Abstract: A rotation angle detection device for detecting a rotation angle of a rotating body includes a magnet disposed to rotate together with the rotating body, a magnetic portion provided in a ring shape radially outward of the magnet, a plurality of gaps being formed in the magnetic portion at a plurality of locations along a circumferential direction, and a magnetic detection unit arranged in a particular gap of the plurality of gaps. The magnetic detection unit is located at a detection position, a width of the particular gap in the tangential direction at the detection position is defined as a detection position gap width, a width of the particular gap in the tangential direction at a position radially outward of the detection position is defined as a tangential width, and the tangential width is narrower than the detection position gap width.

Abstract: An output terminal of a signal output device is connected through a branch path to a voltage dividing point in a main path, and transmits an output signal based on a voltage of the voltage dividing point to an outside. A signal generation circuit adjusts the voltage of the voltage dividing point and generates the output signal. A short circuit detection circuit detects a short circuit between the output terminal and another terminal when a current flowing in the branch path is greater than a predetermined short circuit detection threshold. A switching circuit switches a current carrying capacity or a configuration of the signal generation circuit to limit a short circuit current flowing in the branch path when the short circuit is detected. The short circuit current is set to a value equal to or greater than the short circuit detection threshold and less than a current upper limit value.

Abstract: A communication apparatus operates with a supply voltage of a power and transmits a sensor value with a digital communication method using consecutive frames. In the communication apparatus, a data source unit is configured to generate a frame using a data of a sensor value processed by a signal processing unit. A switching unit is configured to perform a signal switching to permit a transmission circuit to perform a re-transmission of re-transmitting a signal including the sensor value stored in a memory in response to a restoration of the power after an instantaneous power interruption. A frame monitoring unit is configured to monitor a status of a frame transmission and determine a frame at the occurrence of the instantaneous power interruption. The sensor value to be re-transmitted is determined based on information of the frame determined by the frame monitoring unit at the occurrence of the instantaneous power interruption.

Abstract: An IC package includes a magnetic detection element, multiple lead lines electrically connected to the magnetic detection element, and multiple terminal lines weldable to the lead lines respectively. A first welding portion, in which a first lead line of the multiple lead lines is welded to a first terminal line of the multiple terminal lines, is not on vertical lines that pass through second welding portions in which the second lead lines of the multiple lead lines are welded to the second terminal lines of the multiple terminal lines respectively. The second lead lines are adjacent to the first lead line. The vertical lines are orthogonal to center axes of the second lead lines.

Abstract: A position detection device is configured to detect a position of a detection target. The position detection device includes: an IC package including a magnetic detection element configured to output a signal that depend on a direction or a strength of an ambient magnetic field, a sealing portion in which the magnetic detection element is sealed, and lead lines, which are projected from the sealing portion and are electrically connected to the magnetic detection elements; terminal lines electrically connectable to the lead lines respectively; and a lead guide placed along the lead lines to restrict positional deviation of the lead lines.

Abstract: A signal output device is provided in a communication apparatus. The communication apparatus communicates with a different one of the communication apparatus using a single line. The signal output device includes a signal output unit. The signal output unit includes a first filter and a second filter. The first filter is provided by a Bessel filter. The second filter is provided by a Chebyshev filter or a Butterworth filter. The signal output unit outputs a signal which is obtained by passing a predetermined signal through the first filter and the second filter. The signal output from the signal output unit has a pass characteristic of the first filter and a pass characteristic of the second filter. A cutoff frequency of the first filter is set to be lower than a cutoff frequency of the second filter.

Abstract: A signal output device is provided in a communication apparatus. The communication apparatus communicates with a different one of the communication apparatus using a single line. The signal output device includes a signal output unit. The signal output unit includes a first filter and a second filter. The first filter is provided by a Bessel filter. The second filter is provided by a Chebyshev filter or a Butterworth filter. The signal output unit outputs a signal which is obtained by passing a predetermined signal through the first filter and the second filter. The signal output from the signal output unit has a pass characteristic of the first filter and a pass characteristic of the second filter. A cutoff frequency of the first filter is set to be lower than a cutoff frequency of the second filter.