Granted Patent B2

US 8,737,029 · App. 13/318,158 · Granted May 27, 2014

Abstract

Claims (20)

1. An integrated circuit, comprising:

a power supply node being connectable to a voltage supply (Vdd);

a ground node connectable to ground (GND);

an electrostatic discharge protection structure operable to divert an electrostatic discharge away from protected parts of the integrated circuit;

a gated domain which is supply gated and/or ground gated with respect to said power supply node and/or said ground node, the protected parts of the integrated circuit comprising the gated domain;

a gating switch operable to gate said gated domain relative to said power supply node and/or said ground node, said gating switch enabling in a connecting state, and in a disconnecting state inhibiting, an electrical connection between said gated domain and at least one of: said power supply node and said ground node; and

electrostatic discharge gating control circuitry operable to control said gated domain to be electrically connected to said power supply node and/or said ground node in case of an electrostatic discharge event.

2. An integrated circuit as claimed in claim 1 , wherein said electrostatic discharge gating control circuitry comprises, in addition to said electrical connection, a bypass to said electrical connection between said gated domain and at least one of: said power supply node and said ground node and a bypass switch which enables said bypass in case of an electrostatic discharge event.

3. An integrated circuit as claimed in claim 2 , wherein said gated domain has a local ground (GNDL) connected to said ground node and wherein said bypass switch has a control input connected to said local ground and wherein said bypass switch enables said bypass when a voltage difference between said local ground and said power supply node exceeds a predetermined threshold.

4. An integrated circuit as claimed in claim 3 , wherein said predetermined threshold is 2 V or more and/or 4 V or less.

5. An integrated circuit as claimed in claim 2 , wherein said bypass switch is arranged to enable said bypass in order to divert a negative discharge current and/or to divert a positive discharge current.

6. An integrated circuit as claimed in claim 1 , wherein said electrostatic discharge gating control circuitry includes gating switch control circuitry for controlling said gating switch to be in said connecting state in case of an electrostatic discharge which causes a current flow between said power supply node and ground.

7. An integrated circuit as claimed in claim 1 , wherein:

said gating switch has a control terminal for providing a control voltage and said gating switch is in said connecting state when said control voltage is in a predetermined range, and

said gating switch control circuitry comprises a control switch (M 2 ) for enabling a path connecting said control terminal to a node of a voltage within said predetermined range, in response to at least one parameter of a voltage difference between a node at one side of said gating switch and a node at another side of said gating switch exceeding a rate threshold.

8. An integrated circuit as claimed in claim 7 , wherein said parameter is a rate of change of said voltage difference.

9. An integrated circuit as claimed in claim 7 , wherein said rate threshold is at least 200 Volt per microsecond.

10. An integrated circuit as claimed in claim 1 , wherein said electrostatic discharge gating control circuitry is inactive when said integrated circuit is not subject to an electrostatic discharge event.

11. An integrated circuit package, comprising:

an integrated circuit as claimed in claim 1 ; a cover which at least part said integrated circuit, said package having a first pin connected to said power supply node and a second pin connected to said ground node.

Assignments (31)