Atheros Communications, Inc.

Pericom Semiconductor Corporation

Siu-Weng Simon Wong

William John McFarland

David Kuochieh Su

Chik Patrick Yue

Paul C F Tong

Ping Ping Xu

Wensong Chen

Zhi Qing Liu

ESD protection is provided by local ESD-protection devices between each pad and a common-discharge line (CDL). Each ESD-protection device has p-well or p-substrate taps to a local ground rather than to the CDL, reducing noise coupling from the I/O's through the CDL. Another ESD clamp that bypasses the CDL is provided between each pair of internal power and ground buses. Better protection of core circuits during power-to-ground ESD events is provided by bypassing the CDL since only one ESD clamp rather than two ESD-protection devices must turn on. The ESD clamps and ESD-protection devices can be gate-coupled n-channel transistors with coupling capacitors between the pad and the transistor gate. Devices can also be substrate-triggered transistors or active ESD clamps that include an inverter between a coupling capacitor to the CDL and the n-channel transistor gate.

Direct power-to-ground ESD protection with an electrostatic common-discharge line

An ESD protection circuit uses an inductor to create an electromagnetic resonance in conjunction with the load capacitance of a conventional ESD device. By properly tuning the resonance of this combination, the protective properties of the ESD device can be maintained while minimizing its capacitive load on the main circuit. The inductor can be interposed in various series configurations with the ESD device between the main circuit and a voltage rail; alternatively, the inductor can be connected in various configurations in parallel with the ESD device. The inductor may be implemented as an on-chip inductor using conventional IC fabrication technologies, or may be implemented using IC chip bonding wires as inductors.

System for providing electrostatic discharge protection for high-speed integrated circuits

Growing community of inventors

Palo Alto, CA, United States of America

Siu-Weng Simon Wong