Abstract:
Systems, methods, and apparatus for controlling power semiconductor devices are described. According to one embodiment of the disclosure, there is disclosed a system. The system may include at least one power source for selectively providing power to one or more power semiconductor devices controlled by a gate driver. The gate driver may include at least one controller coupled to at least one power semiconductor device interface via a first channel and a second channel configured to provide galvanic isolation of information communicated between the controller and the at least one power semiconductor device interface.
Abstract:
A system for regulating semiconductor devices may include a current regulator configured to regulate one or more currents provided to an insulated gate bipolar transistor (IGBT). The current regulator may regulate the currents by generating a current profile based at least in part on a collector voltage value associated with the IGBT, a rate of collector voltage change value associated with the IGBT, or any combination thereof The current profile may include one or more current values to be provided to a gate of the IGBT such that the current values are configured to limit the rate of collector voltage change to a first value. The current regulator may then send the one or more current values to a current source configured to supply the gate of the IGBT with one or more currents that correspond to the one or more current values.
Abstract:
A dose counter for use with an inhaler comprising a container for medicament equipped with a reciprocal actuation means to dispense a dose of medicament therefrom, the dose counter comprising: a fixed ratchet member, a trigger member constructed and arranged to undergo reciprocal movement coordinated with the reciprocal movement between the actuation means and the container, said reciprocal movement comprising an outward stroke and a return stroke, a counter member constructed and arranged to undergo a predetermined counting movement each time a dose is dispensed, the counter member being biased towards the ratchet and trigger members and being capable of counting motion in a direction generally orthogonal to the direction of reciprocal movement of the trigger member, the counter member comprising: a first region for interaction with the trigger member which comprises at least one inclined surface which is engaged by the trigger member during its outward stroke causing the counter member to undergo counting motion, and a second region for interaction with the ratchet member which comprises at least one inclined surface which is engaged by the ratchet member during the return stroke of the trigger member causing the counter member to undergo further counting motion to complete said predetermined counting movement.
Abstract:
Grouped gating control logic allows for one or more inputs in a group to be active at any given time. Once an input signal in a group is active, all other pulse trains received in the same group can be locked out. Thus, by using a finite state machine to control gate pulses, the noise margin of the gating unit can be regulated and an extra level of protection is available should one of the input gating signals be defective.
Abstract:
A method of conditioning tantalum capacitors on printed wire assemblies is disclosed. According to the method, each of the capacitors on an assembly is subjected to the same conditioning level during testing. To condition the tantalum capacitors, surge currents are induced in the capacitors in a controlled manner as a way of aging the capacitors so that they can be used without de-rating rating with low failure rates. The level of voltage, timing and current levels are set by circuitry used to perform the testing. The same circuits that are used with the capacitors in a system application are also used for the tantalum capacitor test circuit during the conditioning process.
Abstract:
A dry powder inhaler incorporates a cyclone chamber (4) comprising at least one air inlet (6) and an outlet (10) wherein the configuration of the air inlet (6) and the shape of the chamber (4) is such that in use a reverse flow cyclone is set up in the chamber (4). The chamber (4) further comprises flow disrupter means, e.g. the upper surface (14) of a protrusion (12) from the base, disposed so as in use to restrict air flowing from the base of the chamber (4) in an axial direction.
Abstract:
A method of conditioning tantalum capacitors on printed wire assemblies is disclosed. According to the method, each of the capacitors on an assembly is subjected to the same conditioning level during testing. To condition the tantalum capacitors, surge currents are induced in the capacitors in a controlled manner as a means of aging the capacitors so that they can be used without de-rating rating with low failure rates. The level of voltage, timing and current levels are set by circuitry used to perform the testing. The same circuits that are used with the capacitors in a system application are also used for the tantalum capacitor test circuit during the conditioning process.
Abstract:
A system for regulating semiconductor devices may include a current regulator configured to regulate one or more currents provided to an insulated gate bipolar transistor (IGBT). The current regulator may regulate the currents by generating a current profile based at least in part on a collector voltage value associated with the IGBT, a rate of collector voltage change value associated with the IGBT, or any combination thereof. The current profile may include one or more current values to be provided to a gate of the IGBT such that the current values are configured to limit the rate of collector voltage change to a first value. The current regulator may then send the one or more current values to a current source configured to supply the gate of the IGBT with one or more currents that correspond to the one or more current values.