Electrostatic discharge protection device for high supply voltage operations

Patent metadata

Field	Value
Publication number	US-2018351352-A1
Application number	US-201815973544-A
Country	US
Kind code	A1
Filing date	May 8, 2018
Priority date	Jun 1, 2017
Publication date	Dec 6, 2018
Grant date	—

Abstract

An electrostatic discharge protection device includes a voltage divider, a resistor, a capacitor, a first primary transistor, a second primary transistor, a first control circuit, and a second control circuit. The voltage divider is coupled between a first system terminal and a second system terminal for providing a voltage. The resistor is coupled to the first system terminal, and the capacitor is coupled to the resistor. The first primary transistor and the second primary transistor are coupled in series between the first system terminal and the second system terminal. The first control circuit turns on the first primary transistor when an electrostatic discharge event occurs according to voltages provided by the voltage divider and the resistor. The second control circuit turns on the second primary transistor when the electrostatic discharge event occurs according to voltages provided by the voltage divider and the first control circuit.

First claim

What is claimed is:

1 . An electrostatic discharge protection device, comprising:
a voltage divider coupled to a first system terminal for receiving a first voltage and a second system terminal for receiving a second voltage, and configured to provide at least one voltage between the first voltage and the second voltage; a first resistor having a first terminal coupled to the first system terminal, and a second terminal; a capacitor having a first terminal coupled to the second terminal of the first resistor, and a second terminal; a first primary transistor having a first terminal coupled to the first system terminal, a second terminal, and a control terminal; a second primary transistor having a first terminal coupled to the second terminal of the first primary transistor, a second terminal coupled to the second system terminal, and a control terminal; a first control circuit configured to turn on the first primary transistor when an electrostatic discharge event occurs, and the first control circuit comprising:
a first terminal coupled to the first system terminal;
an input terminal coupled to the second terminal of the first resistor;
a second terminal coupled to the voltage divider for receiving a third voltage between the first voltage and the second voltage; and
an output terminal coupled to the control terminal of the first primary transistor for controlling the first primary transistor; and
a second control circuit configured to turn on the second primary transistor when the electrostatic discharge event occurs, and the second control circuit comprising:
a first terminal coupled to the output terminal of the first control circuit;
an input terminal coupled to the voltage divider for receiving the third voltage or a fourth voltage between the first voltage and the second voltage;
a second terminal coupled to the second system terminal; and
an output terminal coupled to the control terminal of the second primary transistor for controlling the second primary transistor.

2 . The electrostatic discharge protection device of claim 1 , wherein the first control circuit further comprises:
a first P-type transistor having a first terminal coupled to the first terminal of the first control circuit, a second terminal coupled to the output terminal of the first control circuit, and a control terminal coupled to the input terminal of the first control circuit; and a first N-type transistor having a first terminal coupled to the second terminal of the first P-type transistor, a second terminal coupled to the second terminal of the first control circuit, and a control terminal coupled to the input terminal of the first control circuit.

3 . The electrostatic discharge protection device of claim 2 , wherein:
the first N-type transistor is disposed in a deep N-well coupled to the first terminal of the first control circuit; a body terminal of the first P-type transistor is coupled to the first terminal of the first control circuit; and a body terminal of the first N-type transistor is coupled to the second terminal of the first N-type transistor.

4 . The electrostatic discharge protection device of claim 2 , wherein:
a channel length of the first P-type transistor is smaller than a channel length of the first N-type transistor; and a channel width of the first P-type transistor is greater than a channel width of the first N-type transistor.

5 . The electrostatic discharge protection device of claim 2 , wherein the first control circuit further comprises:
a second resistor coupled between the first terminal of the first N-type transistor and the output terminal of the first control circuit.

6 . The electrostatic discharge protection device of claim 1 , wherein the first control circuit further comprises:
a plurality of first P-type transistors, each having a first terminal coupled to the first terminal of the first control circuit, a second terminal coupled to the output terminal of the first control circuit, and a control terminal coupled to the input terminal of the first control circuit; and a plurality of first N-type transistors coupled in series between the output terminal and the second terminal of the first control circuit with control terminals of the plurality of first N-type transistors coupled to the input terminal of the first control circuit.

7 . The electrostatic discharge protection device of claim 1 , wherein the second control circuit further comprises:
a second P-type transistor having a first terminal coupled to the output terminal of the first control circuit, a second terminal coupled to the output terminal of the second control circuit, and a control terminal coupled to the input terminal of the second control circuit; and a second N-type transistor having a first terminal coupled to the output terminal of the second control circuit, a second terminal coupled to the second system terminal, and a control terminal coupled to the input terminal of the second control circuit.

8 . The electrostatic discharge protection device of claim 7 , wherein the second control circuit further comprises:
a third resistor coupled between the first terminal of the second N-type transistor and the output terminal of the second control circuit.

9 . The electrostatic discharge protection device of claim 1 , wherein the second control circuit further comprises:
a second P-type transistor having a first terminal coupled to the first terminal of the second control circuit, a second terminal coupled to the output terminal of the second control circuit, and a control terminal coupled to the input terminal of the second control circuit; and a plurality of second N-type transistors coupled in series between the output terminal of the second control circuit and the second system terminal with control terminals of the plurality of second N-type transistors coupled to the input terminal of the second control circuit.

10 . The electrostatic discharge protection device of claim 9 , wherein:
a channel length of the second P-type transistor is smaller than a channel length of each of the plurality of second N-type transistors; and a channel width of the second P-type transistor is greater than a channel width of each of the plurality of second N-type transistors.

11 . The electrostatic discharge protection device of claim 1 , wherein the second control circuit further comprises:
a plurality of second P-type transistors, each having a first terminal coupled to the first terminal of the second control circuit, a second terminal coupled to the output terminal of the second control circuit, and a control terminal coupled to the input terminal of the second control circuit; and a plurality of second N-type transistors coupled in series between the output terminal of the second control circuit and the second system terminal with control terminals of the plurality of second N-type transistors coupled to the input terminal of the second control circuit.

12 . The electrostatic discharge protection device of claim 11 , wherein:
body terminals of the plurality of second N-type transistors are coupled to the second system node.

13 . The electrostatic discharge protection device of claim 1 , further comprising a second gate resistor coupled between the input terminal of the second control circuit and the voltage divider.

14 . The electrostatic discharge protection device of claim 1 , further comprising:
a third gate transistor coupled between the control terminal of the first primary transistor and the second terminal of the first primary transistor; and a fourth gate transistor coupled bet

Assignees

• Richwave Technology Corp

Inventors

• Chen Yuh-Yue

Classifications

• H02H9/046

  responsive to excess voltage appearing at terminals of integrated circuits · CPC title

• H02H9/044 Primary

  Physical layout, materials not provided for elsewhere (varistors H01C7/12; spark-gaps H01T; Ovshinsky devices H10N70/00) · CPC title

• H01L27/0922

  Electricity · mapped topic

• H01L27/0629

  Electricity · mapped topic

• H01L29/1095

  Electricity · mapped topic