A pulse current application circuit for applying a pulse current to a current application target. The pulse current application circuit includes a first switching element and an inductive load connected in series between a power supply and a reference potential, a second switching element connected in series with the current application target, the second switching element and the current application target being connected between the reference potential and a connection point of the first switching element and the inductive load, and a commutation circuit connected in parallel to the inductive load, the commutation circuit having a current flowing therethrough and having no current flowing therethrough respectively when the second switching element is in a cut-off state and a conductive state.

A system for testing a transient voltage suppressor (TVS) configured to be coupled between a bus and a first ground or line to discharge a voltage surge on the bus to the first ground or line includes a pulse source configured to generate an electrical pulse. The system further includes a transformer having a first side coupled to the pulse source and a second side configured to be coupled to the TVS and configured to transfer the electrical pulse to the TVS and to transfer an at least partial reflection of the electrical pulse from the TVS to the first side. The system also includes a test point coupled to the first side of the transformer and configured to receive the at least partial reflection of the electrical pulse.

Methods and apparatuses for performing optical inspection of varactor diodes in an antenna are disclosed. In some embodiments, the method of testing an antenna having varactor diodes comprises: selecting a plurality of varactor diodes to be placed in a light emitting state; forward biasing the selected varactor diodes to a magnitude at which the selected varactor diodes are to emit light; and detecting one or more faulty varactor diodes of the selected varactor diodes based on their emitted light intensity.

Thermoelectric devices based on diodes. Devices and systems can be used as cooling devices or cooling systems or as energy harvesting devices or energy harvesting systems. System comprising: a diode (3.1) comprising a first end and a second end; at least one thermometer (3.2) attached to said first end of said diode; and a power supply/current generator (3.6). Method of changing the temperature of an element, said method comprising: providing a system comprising: a diode comprising a first end and a second end; a thermometer attached to at least said first end or said second end of said diode; and a power supply/current generator; contacting said first end or said second end of said diode to said element; driving current through or applying voltage to said diode, thereby cooling the first end of said diode and heating the second end of said diode, thereby transferring heat between said diode and said element, thus changing the temperature of said element.

A life estimation circuit includes a temperature detector configured to detect temperature of a power element unit, an inflection point detection unit configured to detect an inflection point of temperature variation in the power element unit based on an output signal from the temperature detector, an operation unit configured to determine an absolute value of a difference between the temperature of the power element unit at an inflection point detected this time and the temperature of the power element unit at an inflection point detected last time, a count circuit configured to count the number of times that the absolute value of the difference in temperature has reached a threshold temperature, and a signal generation unit configured to output, when a count value from the count circuit reaches a threshold number of times, an alarm signal indicating that the power element is about to reach the end of its life.

A system for testing a transient voltage suppressor (TVS) configured to be coupled between a bus and a first ground or line to discharge a voltage surge on the bus to the first ground or line includes a pulse source configured to generate an electrical pulse. The system further includes a transformer having a first side coupled to the pulse source and a second side configured to be coupled to the TVS and configured to transfer the electrical pulse to the TVS and to transfer an at least partial reflection of the electrical pulse from the TVS to the first side. The system also includes a test point coupled to the first side of the transformer and configured to receive the at least partial reflection of the electrical pulse.

A control unit for a motor vehicle, having a supply connection for receiving a supply voltage from a supply line needing to be secured against a reaction from the control unit, wherein to protect against the reaction there is provision in a current path of the supply connection for a unidirectional first blocking element, and a diagnostic circuit is configured to check the blocking effect thereof by a predetermined diagnostic routine. An additional, second unidirectional blocking element is connected in series with the blocking element in the current path of the supply connection, wherein the first and the second blocking element each provide for a unidirectional flow of current to the device circuit, and the diagnostic circuit is configured to use the diagnostic routine to also check the blocking effect of the second blocking element.

Embodiments are directed to a transient protection circuit configured for use in a SSPC having a plurality of power channels. The transient protection circuit includes a shared transient voltage suppressor, and a shared protection line communicatively coupled to the shared transient voltage suppressor. The shared protection line is configured to be communicatively coupled to and shared by the plurality of power channels. When the shared protection line is communicatively coupled to and shared by the plurality of power channels, energy above a threshold on any one of the plurality of power channels is dissipated through the shared protection line and the shared transient voltage suppressor.

A testing circuit includes at least one sub-circuit. The sub-circuit includes a first input end, at least one second input end, at least one third input end, and at least one driving output end. The first switch unit includes controllable switches. The second switch unit includes sub-units and first inverters. The sub-unit includes transmission gates. The control end of the controllable switch connects to the second input end, the first end connects to the first input end, and the second end connects to the input end of the transmission gate. The first control end of the transmission gate connects to the third input end and the input end of the first inverter, the second control end connects to the output end of the first inverter, the output end connects to the driving output end.

A semiconductor test circuit, apparatus, and method having a first relay disposed between a power supply and a switching element, a second relay disposed between a connection point of the switching element and a reverse conducting-insulated gate bipolar transistor (RC-IGBT) chip and a snubber circuit, a third relay disposed between the switching element and the RC-IGBT chip and a coil, and a fourth relay disposed between a diode and the switching element. A turn on/off test of an IGBT portion is performed by turning on the second and fourth relays. An avalanche test of the IGBT portion is performed by turning on the second relay. A short-circuit test of the IGBT portion is performed by turning on the first relay. A recovery test of an FWD portion is performed by turning on the first and third relays. At this time probes are brought into contact with electrodes once.