Provided is a load drive slope control device that can reduce EMI noise, and power loss and heat generation when a drive transistor is turned on and off, and can prevent excessive high temperature-induced damage to the drive transistor at an excessive high temperature. Disclosed is a load drive control device including: a drive transistor that drives a load; a pre-driver that drives the drive transistor via an ON/OFF control terminal of the drive transistor; a capacitor that is connected to an input side of the pre-driver, a first current source that is ON/OFF controlled by a first signal, and generates current which is charged to the capacitor; and a second current source that is ON/OFF controlled by a second signal, and generates current for discharging the capacitor, in which an output voltage from the pre-driver is changed by charging or discharging the capacitor, the drive transistor is turned on and off by the output voltage from the pre-driver, and a linear ascending gradient and a linear descending gradient of the waveform of a voltage driving the load are obtained by turning on and off the drive transistor.

Provided is a load drive slope control device that can reduce EMI noise, and power loss and heat generation when a drive transistor is turned on and off, and can prevent excessive high temperature-induced damage to the drive transistor at an excessive high temperature. Disclosed is a load drive control device including: a drive transistor that drives a load; a pre-driver that drives the drive transistor via an ON/OFF control terminal of the drive transistor; a capacitor that is connected to an input side of the pre-driver, a first current source that is ON/OFF controlled by a first signal, and generates current which is charged to the capacitor; and a second current source that is ON/OFF controlled by a second signal, and generates current for discharging the capacitor, in which an output voltage from the pre-driver is changed by charging or discharging the capacitor, the drive transistor is turned on and off by the output voltage from the pre-driver, and a linear ascending gradient and a linear descending gradient of the waveform of a voltage driving the load are obtained by turning on and off the drive transistor.

A detonator system wherein a detonator is connected via a down-hole harness to a bus extending from a blast controller and wherein a component is connected in series with the down-hole harness to limit leakage current in the harness to a level which can be accommodated by the blast controller.

A detonator system wherein a detonator is connected via a down-hole harness to a bus extending from a blast controller and wherein a component is connected in series with the down-hole harness to limit leakage current in the harness to a level which can be accommodated by the blast controller.

A control circuit for an electronic switch includes a first power switch receiving a common input signal and a first voltage input and a second power switch receiving the common input signal and a second voltage input. The first and second power switches switchably connect the first voltage input and the second voltage input, respectively, to a common output in response to the common input signal. The second voltage input is opposite in polarity to the first voltage input, and the first power switch and the second power switch are configured to asynchronously connect the first voltage input and the second voltage input, respectively, to the common output in response to the common input signal, the electronic switch being switched according to the first voltage input or the second voltage input being connected to the common output.

A semiconductor device of the present invention includes a transistor having a drain and a source, a voltage being applied between the drain and the source from a high-voltage power supply, a drive device that generates a source voltage and a gate voltage for the transistor from a voltage of a low-voltage power supply lower than that of the high-voltage power supply, and a voltage dividing circuit connected to the low-voltage power supply, wherein when the source voltage is lower than a certain value, an output voltage from the voltage dividing circuit is applied to the source.

A semiconductor device of the present invention includes a transistor having a drain and a source, a voltage being applied between the drain and the source from a high-voltage power supply, a drive device that generates a source voltage and a gate voltage for the transistor from a voltage of a low-voltage power supply lower than that of the high-voltage power supply, and a voltage dividing circuit connected to the low-voltage power supply, wherein when the source voltage is lower than a certain value, an output voltage from the voltage dividing circuit is applied to the source.

The invention relates to a circuit arrangement for combined protection of a load from temporary and transient overvoltages with emergency operation of the load in the presence of a temporary overvoltage and with integrated follow current limitation, wherein a first surge arrester, in particular a spark gap or a varistor, is provided between network-side input terminals and a second surge arrester, in particular a varistor, is provided between load-side output terminals for follow current limitation. According to the invention, at least one controlled semiconductor switch is provided in each case in the series branch between the input terminal and the output terminal and in the output-side parallel branch, wherein a mechanical switch and a series capacitance are connected in parallel with the semiconductor switch in the series branch. Furthermore, the semiconductor switch in the parallel branch is part of a series circuit comprising a parallel circuit comprising a second surge arrester and a parallel capacitance. A series inductance is provided in the series branch between the input terminal and the parallel circuit comprising the series capacitance, the controlled semiconductor switch and the mechanical switch. A microcontroller for controlling the semiconductor switches is also present, wherein the microcontroller is connected to a current detector in the series branch.

The invention relates to a circuit arrangement for combined protection of a load from temporary and transient overvoltages with emergency operation of the load in the presence of a temporary overvoltage and with integrated follow current limitation, wherein a first surge arrester, in particular a spark gap or a varistor, is provided between network-side input terminals and a second surge arrester, in particular a varistor, is provided between load-side output terminals for follow current limitation. According to the invention, at least one controlled semiconductor switch is provided in each case in the series branch between the input terminal and the output terminal and in the output-side parallel branch, wherein a mechanical switch and a series capacitance are connected in parallel with the semiconductor switch in the series branch. Furthermore, the semiconductor switch in the parallel branch is part of a series circuit comprising a parallel circuit comprising a second surge arrester and a parallel capacitance. A series inductance is provided in the series branch between the input terminal and the parallel circuit comprising the series capacitance, the controlled semiconductor switch and the mechanical switch. A microcontroller for controlling the semiconductor switches is also present, wherein the microcontroller is connected to a current detector in the series branch.

An electronic control apparatus includes a switching element; an ON-drive constant-current circuit supplying a constant current to the control terminal of the switching element thereby charging the control terminal of the switching element; an OFF-drive switching element discharging electrical charge from the control terminal of the switching element by being turned ON; and a control circuit adapted to control the ON-drive constant-current circuit and the OFF-drive switching element in response to a drive signal being inputted, thereby controlling the voltage of the control terminal of the switching element so as to drive the switching element. The control circuit controls the current control transistor based on the voltage of the current detection resistor and supplies the constant current to the control terminal of the switching element, and detects an abnormality in the ON-drive constant-current circuit based on the voltage of the current detection resistor.