Current leak detection for solid state devices

#The present disclosure relates to the field of current leak detection for solid state devices.

#Solid state devices, such as solid state switches, are used in various applications such as in circuit breakers, e-Fuses, etc. In these types of applications, the solid state devices may remain in the same state for extended periods of time. For example, a solid state device of a circuit breaker may remain in an on state where the solid state device is conducting for years. The solid state device will turn off and close to stop conducting if there is an abnormal condition such as an overload or short circuit. Unfortunately, there is no way to test the solid state device to see if the solid state device is operating correctly and will be able to completely turn off in the event of the abnormal condition. This can result in catastrophic failures and damage.

#This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key factors or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

#FIG. 1A is a component block diagram illustrating a leak detection component for current leak detection of a solid state device in accordance with at least some of the techniques presented herein.

#FIG. 1B is a component block diagram illustrating a leak detection component for current leak detection of a solid state device using a capacitor in accordance with at least some of the techniques presented herein.

#FIG. 10 is a component block diagram illustrating a leak detection component for current leak detection of a solid state device using a voltage source in accordance with at least some of the techniques presented herein.

#The claimed subject matter is now described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the claimed subject matter. It may be evident, however, that the claimed subject matter may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to facilitate describing the claimed subject matter.

#Various devices, such as e-Fuses and circuit breakers, may utilize solid state devices that operate in either an on state or an off state. These solid state devices may comprise solid state switches, metal-oxide-semiconductor field-effect transistors (MOSFETs), etc. A solid state device may transition from one of the states to another state based upon a voltage applied to a gate of the solid state device. Once the voltage of the gate reaches a threshold voltage Vth, then the solid state device may change states, such as where the solid state device is turned on and starts conducting. In certain applications, the solid state device may remain in a particular state for an extended period of time. This period of time could be years, such as where a solid state device of a circuit breaker is in an on state until an abnormal condition of an electric supply network occurs such as an overload or short circuit. Because the solid state device remains in one state for such a long period of time, there is no way to verify that the solid state device is operating correctly and will be able to transition states when needed such as to safely turn off when the abnormal condition occurs. This can lead to catastrophic failures and damage.

#The health and operability of the solid state device may deteriorate over time due to various reasons such as stress on the solid state device. One issue that can occur is that the threshold voltage Vth of the gate can drift over time, which can lead to excessive leakage current, leakage current due to a drain source on resistance (RDSon) being too low, and/or failure where the solid state device cannot switch states such as to turn off safely. As the threshold voltage Vth drifts towards 0, the solid state device may not even be able to turn off. High leakage currents due to this drift causes health deterioration of the apparatus comprising the solid state device, such as where there is always current flowing through the solid state device to a secondary side of the apparatus. This could lead to a high voltage condition on the secondary side that should otherwise be turned off. If the solid state device cannot completely shut off, then the solid state device will operate similar to a current source and deliver a significant amount of current (e.g., 10 to 100 milliamps) that can cause overheating and failure due to damage from thermal overstress behavior. The drift of the threshold voltage Vth can occur over a long period of time, and thus the leakage current may slowly increase over time. There is currently no ability to detect this slow drift and leakage current increase in-situ during operation of the apparatus comprising the solid state device.