A power supply with lightning protection includes a surge voltage suppression apparatus, an electromagnetic interference control circuit, a surge current bypass apparatus, an active bridge rectifier circuit, a power factor correction circuit, and a DC-to-DC conversion circuit. The surge voltage suppression apparatus is used to increase a tolerance of a surge voltage for the power supply. The electromagnetic interference control circuit is coupled to the surge voltage suppression apparatus. The surge current bypass apparatus is used to increase a tolerance of a surge current for the power supply. The active bridge rectifier circuit is used to rectify an input voltage. The power factor correction circuit is used to adjust the rectified input voltage to provide an adjusted input voltage on a bulk capacitor. The DC-to-DC conversion circuit is used to convert the adjusted input voltage into a DC output voltage.

A power supply with lightning protection includes a surge voltage suppression apparatus, an electromagnetic interference control circuit, a surge current bypass apparatus, an active bridge rectifier circuit, a power factor correction circuit, and a DC-to-DC conversion circuit. The surge voltage suppression apparatus is used to increase a tolerance of a surge voltage for the power supply. The electromagnetic interference control circuit is coupled to the surge voltage suppression apparatus. The surge current bypass apparatus is used to increase a tolerance of a surge current for the power supply. The active bridge rectifier circuit is used to rectify an input voltage. The power factor correction circuit is used to adjust the rectified input voltage to provide an adjusted input voltage on a bulk capacitor. The DC-to-DC conversion circuit is used to convert the adjusted input voltage into a DC output voltage.

Overvoltage protection circuits are provided. In some embodiments, an overvoltage protection circuit includes a first diode made of a first semiconductor material having a bandgap width greater than that of silicon. A second diode is included and is electrically cross-coupled with the first diode. The second diode is made of a second semiconductor material different from the first semiconductor material.

An Electrostatic Discharge protection circuit with low parasitic capacitance is provided, comprising a first bipolar junction transistor and a first ESD power clamp device. The first bipolar junction transistor is an NPN type of bipolar junction transistor, including a base and an emitter commonly connected to an I/O terminal and a collector connected with the first ESD power clamp device. The first ESD power clamp device is further connected to ground, and can be a Zener diode, PNP type, NPN type of bipolar junction transistor or the like. When a positive ESD pulse is injected, an ESD protection path is consisting of the first bipolar junction transistor and the first ESD power clamp device. When a negative ESD pulse is injected, the ESD protection path is consisting of a parasitic silicon controlled rectifier, thereby reducing parasitic capacitance effectively.

In some aspects, the techniques described herein relate to an electromagnetic interference (EMI) filter circuit including: an input terminal; an output terminal; an electrical ground terminal; a resistor electrically coupled between the input terminal and the output terminal; a first bipolar transistor including: a collector terminal electrically coupled with the input terminal; an emitter terminal electrically coupled with the electrical ground terminal; and a base terminal that is electrically floating; and a second bipolar transistor including: a collector terminal electrically coupled with the output terminal; an emitter terminal electrically coupled with the electrical ground terminal; and a base terminal that is electrically floating.

A crowbar module includes first and second electrical terminals, a module housing, and first and second crowbar units. The first crowbar unit is disposed in the module housing and includes a first thyristor electrically connected between the first and second electrical terminals. The second crowbar unit is disposed in the module housing and includes a second thyristor electrically connected between the first and second electrical terminals in electrical parallel with the first crowbar unit.

A power system a method for enhanced voltage protection. The system may comprise a surface high voltage power supply, a voltage controller connected to the surface high voltage power supply that sends commands to the surface high voltage power supply to control an output voltage of the surface high voltage power supply, one or more power cables attached to the surface high voltage power supply, a downhole tool connected to the one or more power cables at an end opposite of the surface high voltage power supply, and a dynamic clamp circuit connected to the surface high voltage power supply. A method may comprise creating a setpoint with a dynamic clamp circuit based at least in part on the command, activating the dynamic clamp circuit when the output voltage is higher than the setpoint, and absorbing excess energy from the high voltage power supply with the dynamic clamp circuit.

Systems and methods herein use a sensing circuit to detect an overvoltage at a voltage node as a drain current. A current-mode comparator converts the detected current into a control signal, which is provided to a control circuit. The control circuit uses the control signal cut of a bias current to turn off switches in a protection circuit to create a high-impedance electrical path between the voltage node and the to-be-protected voltage node.

Systems and methods herein use a sensing circuit to detect an overvoltage at a voltage node as a drain current. A current-mode comparator converts the detected current into a control signal, which is provided to a control circuit. The control circuit uses the control signal cut of a bias current to turn off switches in a protection circuit to create a high-impedance electrical path between the voltage node and the to-be-protected voltage node.

An anti-fuse having two electrical connections is constructed by adding at least one zener diode and resistor to a power MOSFET. When the voltage across the two electrical connections exceeds the zener diode voltage and the maximum gate voltage of the MOSFET, the MOSFET burns out. This shorts out the device which can be used to bypass an LED or other load when that load burns out and forms an open circuit.