Texas Instruments Corporation

Krishna Praveen Mysore Rajagopal

Ann Margaret Concannon

Mariano Dissegna

Akram Ali Salman

James Paul Di Sarro

Aravind Chennimalai Appaswamy

Antonio Gallerano

Muhammad Yusuf Ali

Jun Cai

Rajkumar Sankaralingam

Vishwanath Joshi

James Paul DiSarro

Lihui Wang

Described examples include an integrated circuit includes a protected node and a first transistor having a source coupled to the protected node, a gate and a drain coupled to a ground, wherein the first transistor is a MOSFET transistor. The integrated circuit also includes a second transistor having a first current handling terminal coupled to the protected node, a second current handling terminal coupled to the ground and a control terminal coupled to a reference potential, where the second transistor is configured to be off when a first voltage on the control terminal of the second transistor is less than a second voltage on the first current handling terminal of the second transistor.

Electrostatic discharge protection circuit

An ESD protection system including structure to operate an IC during nominal conditions, to protect the IC during an ESD event, and to allow the IC to operate during slow rising input node voltages that exceed nominal conditions.

Electrostatic discharge protection system

Disclosed examples provide an ESD protection circuit including a protection structure to selectively conduct current between a first terminal at a protected node and a second terminal at a reference node in response to the protected node voltage and a control voltage signal rising above a trigger voltage during an ESD event, and a bias circuit configured to bias a protection structure control terminal at a control voltage corresponding to a higher one of a first voltage of the first terminal and a second voltage of the second terminal to control the trigger voltage of the ESD protection structure to keep the ESD protection structure off during normal operation.

Self-biased bidirectional ESD protection circuit

A semiconductor device contains a Zener-triggered transistor having a Zener diode vertically integrated in a first current node of the Zener-triggered transistor. The first current node includes an n-type semiconductor material contacting a p-type semiconductor material in a substrate. The Zener diode includes an n-type cathode contacting the first current node, and a p-type anode contacting the n-type cathode and contacting the p-type semiconductor material. The semiconductor device may be formed using an implant mask, with an opening for the Zener diode. Boron and arsenic are implanted into the substrate in an area exposed by the opening in the implant mask. The substrate is subsequently heated to diffuse and activate the implanted boron and arsenic. The Zener-triggered transistor may be used in an ESD circuit or a snubber circuit.

Zener-triggered transistor with vertically integrated Zener diode

A semiconductor device has a protected line connected to a ground line by a triggered clamp. A variable shunt, which includes a depletion mode JFET, is connected between the protected line and the ground line, in parallel with the triggered clamp. The depletion mode JFET is formed in a substrate of the semiconductor device. The channel of the depletion mode JFET provides a resistive path for the variable shunt when the semiconductor device is unpowered, to dissipate charge from the powered line after an ESD event. When the semiconductor device is operated, that is, powered up, the gate of the depletion mode JFET may be biased to turn off the channel, and so reduce impairment of operation of the semiconductor device.

ESD network comprising variable impedance discharge path

Disclosed examples include an ESD protection circuit, including a transistor operative according to a control voltage signal at a control node to selectively conduct current from a protected node to a reference node during an ESD event, as well as a resistor connected between the control node and the reference node, a capacitor connected between the control node and an internal node, and a diode with an anode connected to the protected node and a cathode connected to the internal node to allow charging current to flow from the protected node to charge the capacitor and to provide a high impedance to the internal node to prevent or mitigate flow of leakage current from the internal node to the protected node to raise a trigger voltage of the protection circuit during normal operation.

ESD protection circuit with passive trigger voltage controlled shut-off

In some examples, an electrostatic discharge (ESD) device comprises an insulated-gate bipolar transistor (IGBT) comprising a source terminal, an anode terminal, a gate terminal, and a body terminal; and at least one reverse bias device comprising a first terminal and a second terminal, wherein the first terminal couples to the source terminal and the second terminal couples to the body terminal.

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Santa Clara, CA, United States of America

Krishna Praveen Mysore Rajagopal