Some embodiments include a high voltage, high frequency switching circuit. The switching circuit may include a high voltage switching power supply that produces pulses having a voltage greater than 1 kV and with frequencies greater than 10 kHz and an output. The switching circuit may also include a resistive output stage electrically coupled in parallel with the output and between the output stage and the high voltage switching power supply, the resistive output stage comprising at least one resistor that discharges a load coupled with the output. In some embodiments, the resistive output stage may be configured to discharge over about 1 kilowatt of average power during each pulse cycle. In some embodiments, the output can produce a high voltage pulse having a voltage greater than 1 kV and with frequencies greater than 10 kHz with a pulse fall time less than about 400 ns.

Some embodiments include a high voltage, high frequency switching circuit. The switching circuit may include a high voltage switching power supply that produces pulses having a voltage greater than 1 kV and with frequencies greater than 10 kHz and an output. The switching circuit may also include a resistive output stage electrically coupled in parallel with the output and between the output stage and the high voltage switching power supply, the resistive output stage comprising at least one resistor that discharges a load coupled with the output. In some embodiments, the resistive output stage may be configured to discharge over about 1 kilowatt of average power during each pulse cycle. In some embodiments, the output can produce a high voltage pulse having a voltage greater than 1 kV and with frequencies greater than 10 kHz with a pulse fall time less than about 400 ns.

A driving device is configured to drive a power semiconductor switch module based on a main control signal. The driving device includes a voltage-modulating unit and a driving module. When the voltage-modulating unit receives a protection signal, the voltage-modulating unit generates a turn-off pulse signal based on the protection signal. Moreover, the driving module is configured to turn off the power semiconductor switch module based on the turn-off pulse signal. Also disclosed herein is a driving method.

A driving device is configured to drive a power semiconductor switch module based on a main control signal. The driving device includes a voltage-modulating unit and a driving module. When the voltage-modulating unit receives a protection signal, the voltage-modulating unit generates a turn-off pulse signal based on the protection signal. Moreover, the driving module is configured to turn off the power semiconductor switch module based on the turn-off pulse signal. Also disclosed herein is a driving method.

A designed waveform generator includes at least one first signal generator including a first switching device and generating a square wave having a constant voltage level during an on-period of the first switching device and at least one second signal generator including a second switching device and controlling a transition period of the second switching device to generate a variable waveform having a variable voltage level during the transition period of the second switching device. The at least one first signal generator and the at least one second signal generator are connected to each other in a cascade manner.

A signal generating device including a first circuit coupled between a first reference voltage and a second reference voltage and arranged to generate a first current to a first BJT; a first control circuit connected to the first BJT and arranged to adjust the first current. The first circuit outputs a part of a temperature-dependent signal on an output terminal, and includes: a first active device having a first and a second connecting terminal coupled to the first BJT; a second active device having a first connecting terminal coupled to the first BJT, and a second connecting terminal coupled to a second reference voltage; a first amplifier having an input terminal coupled to the first BJT, and an output terminal coupled to the control terminal of the first active device; and a second control circuit coupled to the first circuit for controlling the temperature-dependent signal according to the first current.

A signal generating device including a first circuit coupled between a first reference voltage and a second reference voltage and arranged to generate a first current to a first BJT; a first control circuit connected to the first BJT and arranged to adjust the first current. The first circuit outputs a part of a temperature-dependent signal on an output terminal, and includes: a first active device having a first and a second connecting terminal coupled to the first BJT; a second active device having a first connecting terminal coupled to the first BJT, and a second connecting terminal coupled to a second reference voltage; a first amplifier having an input terminal coupled to the first BJT, and an output terminal coupled to the control terminal of the first active device; and a second control circuit coupled to the first circuit for controlling the temperature-dependent signal according to the first current.

An apparatus and method are provided to correct for time-walk errors during photon detections (e.g., detecting gamma rays). A time-walk correction is determined using measurements of energy (or charge) that apply different time windows, enabling corrections accounting for variations in the ratio between fast and slow components in the detected pulse. For example, one time window can be used to integrate the leading end of the pulse, thereby predominantly measuring the fast component, while a second window is used to integrate a trailing end of the pulse to predominantly measure the slow component. Alternatively or additionally, low-pass and high-pass filters may select the slow and fast components, respectively. The time-walk correction is a function of multiple measurements representing different components (e.g., fast and slow) of the pulse shape.

A defibrillator of the present disclosure includes a H-bridge type biphasic pulse generation circuit connected to the rear stage side of a high-voltage capacitor. The biphasic pulse generation circuit includes a first switch, a second switch connected in parallel to the first switch, a third switch connected in series and to the rear stage side of the first switch, and a fourth switch connected in series and to the rear stage side of the second switch. The biphasic pulse generation circuit outputs a biphasic pulse from a first output line connected to a connection intermediate point between the first and third switches and from a second output line connected to a connection intermediate point between the second and fourth switches. In at least one of the first switch to the fourth switch, a plurality of thyristors are connected in series, and a resistor is connected in parallel to each thyristor.

A defibrillator of the present disclosure includes a H-bridge type biphasic pulse generation circuit connected to the rear stage side of a high-voltage capacitor. The biphasic pulse generation circuit includes a first switch, a second switch connected in parallel to the first switch, a third switch connected in series and to the rear stage side of the first switch, and a fourth switch connected in series and to the rear stage side of the second switch. The biphasic pulse generation circuit outputs a biphasic pulse from a first output line connected to a connection intermediate point between the first and third switches and from a second output line connected to a connection intermediate point between the second and fourth switches. In at least one of the first switch to the fourth switch, a plurality of thyristors are connected in series, and a resistor is connected in parallel to each thyristor.