Abstract: A motor drive device (1a) includes: chopping signal generation means (151, 153) for generating a chopping signal Sa when drive current of a driver (14) has reached a first threshold value; chopping signal cut-off means (152, 154) for cutting off the chopping signal Sa when the drive current has reached a second threshold value which is greater than the first threshold value; and overcurrent protection means (16) for generating an overcurrent protection signal Se when the drive current has reached a third threshold value which is greater than the first threshold value and its continuation time has reached a predetermined threshold value time. Thus it is possible to simultaneously obtain the constant current chopping function and the overcurrent protection function and to improve its reliability and safety.

Abstract: In a semiconductor integrated circuit device of the invention, a plurality of external terminals include: a first external terminal (VCC, U, V and W terminals in the FIGURE) receiving a higher voltage than the other external terminals; and a second external terminal (FG terminal in the FIGURE) arranged adjacent to the first external terminal as one of the other external terminals, the second external terminal feeding out, from one end of a transistor Q1, a control pulse signal corresponding to the turning on and off of the transistor Q1, and the second external terminal is connected to an overvoltage protection circuit (consisting of R1, R2, Q2 and AND) that masks a control signal for turning on and off the transistor Q1 so that, when a voltage at the second external terminal reaches a predetermined threshold, the transistor Q1 is kept off all the time.

Abstract: A power semiconductor drive circuit device includes: an electronic control device generating a control input signal; a signal transfer circuit device having a main path and a self-diagnosis functional block; and a power semiconductor driven by the control output signal from the signal transfer circuit device. The self-diagnosis functional block includes: a feedback pulse transmitter circuit; a second signal transfer circuit; and a second receiver circuit. The second receiver circuit compares the control output signal with the control input signal so as to find out whether the control output signal is matched or unmatched with the control input signal, and then outputs a result to a comparison signal output terminal. A signal outputted to the comparison signal output terminal is transferred to the electronic control device.

Abstract: A current limiter circuit in an IC having a power transistor and an output current detection circuit connected in series with the power transistor. A comparator, a first reference voltage generator circuit and a second reference voltage generator circuit are also included in the current limiter circuit. The comparator generates a control signal for stopping a drive of the power transistor for a predetermined time. The comparator generates the control signal according to a detection signal obtained by the output current detection circuit and a second reference voltage obtained by the second reference voltage generator circuit when the output current of the power transistor reaches a predetermined value larger than the predetermined limit value. The first reference voltage generator circuit is provided externally of the IC and the second reference voltage generator circuit is included within the IC.

Abstract: A switching regulator is provided with: a comparator producing a comparison signal by comparing a feedback voltage commensurate with an output voltage with a predetermined reference voltage; an oscillator producing a clock signal at a predetermined frequency; a latch circuit producing a pulse width modulation signal with a desired duty factor based on the comparison signal and the clock signal; an output transistor for which switching control is performed based on the pulse width modulation signal, the output transistor having one end from which a switching voltage in the form of a rectangular wave is outputted; and a phase compensation circuit connected between an output terminal of the latch circuit and a feedback voltage input terminal of the comparator.

Abstract: A semiconductor integrated circuit device comprises a first terminal (denoted by VCC) connected to a power supply in a normally mounted state, a second terminal (denoted by SB) connected to a signal line in the normally mounted state and to a power supply in a reversely mounted state, a third terminal (denoted by SGND) connected to the ground in the normally mounted state, fourth terminals (denoted by HU?, HW?) connected to the signal line in the normally mounted state and to the ground in the reversely mounted state, electrostatic protective diodes (denoted by D1, D6) having anodes connected to the third terminal and cathodes connected to the fourth terminals and serving as means for protecting the fourth terminal in the normally mounted state, a current control resistor (R1) having one end connected to the second terminal and serving as means for preventing the second terminal from being broken in the reversely mounted state, a Zener diode (ZD) having an anode connected to the third terminal and a cathode c

Abstract: In a semiconductor integrated circuit device of the invention, a plurality of external terminals include: a first external terminal (VCC, U, V and W terminals in the FIGURE) receiving a higher voltage than the other external terminals; and a second external terminal (FG terminal in the FIGURE) arranged adjacent to the first external terminal as one of the other external terminals, the second external terminal feeding out, from one end of a transistor Q1, a control pulse signal corresponding to the turning on and off of the transistor Q1, and the second external terminal is connected to an overvoltage protection circuit (consisting of R1, R2, Q2 and AND) that masks a control signal for turning on and off the transistor Q1 so that, when a voltage at the second external terminal reaches a predetermined threshold, the transistor Q1 is kept off all the time.

Abstract: A driver circuit of the present invention includes: a pair of switch elements (P1, N1) connected in series between a ground terminal and a stepped-up voltage VCP application terminal to which a stepped-up voltage VCP is applied; and a clamp element ZD1 connected between a node A between the pair of switch elements and an output terminal T2, the driver circuit driving, according to a voltage signal derived from the node A, an N-channel output transistor Q1 connected between the output terminal T2 and a power supply voltage VCC application terminal to which a power supply voltage VCC is applied. Here, a current control section (IL1, IL2) formed of a resistor and a capacitor that are connected in parallel with each other is inserted in at least one of a current path that connects the node A and the stepped-up voltage VCP application terminal and a current path that connects the node A and the ground terminal.

Abstract: An over-current protection circuit of a semiconductor circuit including a power transistor for outputting current output, a first output current detection circuit and a current limiter circuit for limiting the output current by stopping the output current of the power transistor for a predetermined period in response to a first detection signal from the output current detection circuit when the output current of the power transistor reaches a predetermined limit value. The over-current protection circuit has an output current detection transistor current-mirror connected to the power transistor and a second output current detection circuit for generating a second detection signal according to an output current of the output current detection transistor when the output current reaches the predetermined limit value. Further, the output current of the power transistor is cut off for the predetermined period by operating the current limiter circuit in response to the second detection signal.

Abstract: A switching regulator is provided with: a comparator producing a comparison signal by comparing a feedback voltage commensurate with an output voltage with a predetermined reference voltage; an oscillator producing a clock signal at a predetermined frequency; a latch circuit producing a pulse width modulation signal with a desired duty factor based on the comparison signal and the clock signal; an output transistor for which switching control is performed based on the pulse width modulation signal, the output transistor having one end from which a switching voltage in the form of a rectangular wave is outputted; and a phase compensation circuit connected between an output terminal of the latch circuit and a feedback voltage input terminal of the comparator.

Abstract: An electric device includes a booster circuit. When a switch control circuit detects abnormal lowering of a second voltage provided from the booster circuit while the booster circuit is boosting a first voltage, the switch control circuit changes a switch from an on state to an off state. This cuts off electrical connection between an anode of a diode and a power supply node. For example, when a second node is grounded, the second voltage lowers. At this time, the switch control circuit changes the switch from the on state to the off state. This can prevent flow of an excessive current through the diode when the second node is grounded. Therefore, the booster circuit with a protection function as well as the electric device with this booster circuit can be provided.

Abstract: The present invention was made to develop a new material possessing simultaneously the two properties of geometrically frustrated state having a magnetic controllability and good conductivity which leads to applications for electrical controllability and thermal storage. This object is achieved by the conductive material having the pyrochlore structure represented by the general formula R2Ir2O7, where R is a rare earth element or elements of La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and Y. When, especially, R is an element or elements of La, Ce, Pr, Nd, Pm, Sm and Eu, the material possesses metallic electrical conductivity, so that it is useful for magnetically controllable functional electronic materials and thermal storage materials having large thermal capacity.

Abstract: The present invention was made to develop a new material possessing simultaneously the two properties of geometrically frustrated state having a magnetic controllability and good conductivity which leads to applications for electrical controllability and thermal storage. This object is achieved by the conductive material having the pyrochlore structure represented by the general formula R2Ir2O7, where R is a rare earth element or elements of La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and Y. When, especially, R is an element or elements of La, Ce, Pr, Nd, Pm, Sm and Eu, the material possesses metallic electrical conductivity, so that it is useful for magnetically controllable functional electronic materials and thermal storage materials having large thermal capacity.