An ESD protection circuit includes a trigger transistor that is responsive to a detection signal indicating an ESD event. The trigger transistor pulls the voltage of a hold node towards a voltage of a power supply rail in response to the detection signal indicating an ESD event. The ESD protection circuit includes a replica trigger transistor whose leakage current controls current provided to the hold node after the detection signal no longer indicates an ESD event to compensate for leakage current through the trigger transistor.

A system and method for combining positive and negative voltage electrostatic discharge (ESD) protection into a clamp that uses cascoded circuitry, including detecting, by an electrostatic discharge protection system, a voltage pulse on an input pin of an integrated circuit (IC) controller, the IC controller coupled between a power supply node and a ground supply node; determining, by the ESD protection circuit, an ESD event on the input pin based on the voltage detected on the input pin; and/or controlling, by the ESD protection circuit during the ESD event, one or more clamps to transport the voltage pulse from the input pin of the IC controller to the power supply node.

A device is disclosed herein. The device includes a bias generator, an ESD driver, and a logic circuit. The bias generator includes a first transistor. The ESD driver includes a second transistor and a third transistor coupled to each other in series. The logic circuit is configured to generate a logic control signal. A first terminal of the first transistor is configured to receive a reference voltage signal, a control terminal of the first transistor is configured to receive a detection signal in response to an ESD event being detected, a second terminal of the first transistor is coupled to a control terminal of the third transistor, and a control terminal of the second transistor is configured to receive the logic control signal.

An electrostatic discharge (ESD) protection circuit includes a first diode, a second diode, an ESD clamp circuit and a first conductive structure on a backside of a semiconductor wafer, and being coupled to the first voltage supply. The first diode is in the semiconductor wafer, and coupled between an IO pad and a first node. The second diode is in the semiconductor wafer, coupled to the first diode and coupled between the IO pad and a second node. The ESD clamp circuit is in the semiconductor wafer, coupled between the first node and the second node, and further coupled to the first and second diode. The ESD clamp circuit includes a first signal tap region in the semiconductor wafer that is coupled to a first voltage supply. The first diode is coupled to and configured to share the first signal tap region with the ESD clamp circuit.

High voltage clamps with transient activation and activation release control are provided herein. In certain configurations, an integrated circuit (IC) includes a clamp electrically connected between a first node and a second node and having a control input. The IC further includes a first resistor-capacitor (RC) circuit that activates a detection signal in response to detecting a transient overstress event between the first node and the second node, an active feedback circuit that provides feedback from the first node to the control input of the clamp in response to activation of the detection signal, a second RC circuit that activates a shutdown signal after detecting passage of the transient overstress event based on low pass filtering a voltage difference between the first node and the second node, and a clamp shutdown circuit that turns off the clamp via the control input in response to activation of the shutdown signal.

In accordance with an embodiment, a semiconductor device includes: an n-doped region disposed over an insulating layer; a p-doped region disposed over the insulating layer adjacent to the n-doped region, where an interface between the n-doped region and the p-doped region form a first diode junction; a plurality of segmented p-type anode regions disposed over the insulating layer, each of the plurality of segmented p-type anode regions being surrounded by the n-doped region, where a doping concentration of the plurality of segmented p-type anode regions is greater than a doping concentration of the p-doped region; and a plurality of segmented n-type cathode regions disposed over the insulating layer. Each of the plurality of segmented n-type cathode regions are surrounded by the p-doped region, where a doping concentration of the plurality of segmented n-type cathode regions is greater than a doping concentration of the n-doped region.

An integrated circuit includes a signal pad, receiving an input signal during a normal mode, and receive an ESD signal during an ESD mode; an internal circuit, processing the input signal during the normal mode; a variable impedance circuit, comprising a first end coupled to the signal pad, a second end coupled to the internal circuit, wherein the variable impedance circuit provides a low or high impedance path between the signal pad and the internal circuit during the normal or ESD mode; and a switch circuit, comprising a first end coupled to a control end of the variable impedance circuit, a second end coupled to a reference voltage terminal, and a control end receiving a node voltage, wherein the switch circuit switches the control end of the variable impedance circuit to have a first specific voltage or be electrically floating during the normal or ESD mode.

An ESD clamp circuit has an ESD detection circuit connected between a first terminal and a second terminal, with a first output node and a second output node. The ESD detection circuit is configured to output respective first and second control signals at the first and second output nodes in response to an ESD event. A discharge circuit includes a p-type transistor having a source, a drain and a gate, with the gate connected to the first output node. An n-type transistor has a source, a drain and a gate, with the gate connected to the second output node. The drain is connected to the drain of the p-type transistor. The discharge circuit is configured to establish a first ESD discharge path from the first terminal, through the p-type transistor and the n-type transistor, to the second terminal, and to further establish a second ESD discharge path in parallel with the first ESD discharge path. The second ESD discharge path includes a parasitic silicon controlled rectifier (SCR).

The present disclosure provides an electrostatic discharge (ESD) protection circuit and a chip. The ESD protection circuit is connected between a power supply VDD and a ground VSS, and includes a filter branch, a first inverter group, a switch transistor, a clamp transistor, a feedback transistor, and a second inverter group. The first inverter group has two terminals respectively connected to a first node and a second node. The switch transistor has a gate connected to the second node. The clamp transistor has a gate connected to a fourth node. The feedback transistor has a gate connected to the fourth node. The second inverter group has two terminals respectively connected to a third node and the fourth node.

The present invention provides an ESD protection circuit including a control circuit, a first transistor, a filter and a second transistor. The control circuit is configured to detect a level of a supply voltage to generate a control signal. The first transistor is coupled between the supply voltage and a ground voltage, and is used to refer to the control signal to determine whether to be enabled as a discharging path for the supply voltage to discharge current to the ground voltage. The filter is configured to filter the control signal to generate a filtered control signal. The second transistor is coupled between the supply voltage and the ground voltage, and is used to refer to the filtered control signal to determine whether to be enabled as a discharging path for the supply voltage to discharge current to the ground voltage.