Cypress Semiconductor Corporation

Longitude Flash Memory Solutions Ltd.

Sungkwon Lee

Venkatraman Prabhakar

Ravindra Manohar Kapre

David Michael Rogers

Yan Yi

Dung Ho

Timothy John Williams

Igor G Kouznetsov

Eric N Mann

Toru Miyamae

Gyu-Chul Kim

Eric Lee Swindlehurst

Ryuta Nagai

Mimi Xuefeng Zhao Qian

Boo Chin-Hua

Andrew J Walker

Helmut Puchner

Roger J Bettman

Murtuza Lilamwala

Mimi Xuefeng Qian

Myeongseok Lee

Sai Prashanth Dhanraj

Leo F Luquette, Jr

Henry H Yuan

Iman Rezanezhad Gatabi

An electrostatic discharge protection circuit capable of clamping both positive and negative ESD events and passing signals is provided. Generally, the circuit includes a p-channel field-effect transistor (PFET) clamp coupled to a pin to be protected, the PFET clamp including a plurality of PFETs in a DN-well, an n-channel field-effect transistors (NFET) clamp coupled between ground and the pin through the PFET clamp, the NFET clamp including a plurality of NFETs coupled in series, and a bias network for biasing a voltage of the DN well to substantially equal a voltage on the pin when the voltage on the pin is greater than ground potential, and to ground potential when the pin voltage is less than ground potential. The plurality of are PFETs coupled in parallel between the pin and the NFET clamp, each of the PFETs is coupled to the pin though one of a plurality ballast resistors.

ESD protection circuit

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.

Combined positive and negative voltage electrostatic discharge (ESD) protection clamp with cascoded circuitry

A method of performing an operation on a non-volatile memory (NVM) cell of a memory device is disclosed. The pass transistor of the NVM cell is an asymmetric transistor including a source with a halo implant. The source of the pass transistor is coupled to a common source line (CSL) that is shared among NVM cells of a sector of NVM cells. The operation may be performed by applying a first signal to a word line (WLS) coupled to a gate of a memory transistor of the NVM cell and applying a second signal to a bit line (BL) coupled to a drain of the memory transistor of the NVM cell.

Asymmetric pass field-effect transistor for nonvolatile memory

Asymmetric pass field-effect transistor for non-volatile memory

A device including both drain extended metal-on-semiconductor (DE_MOS) and low-voltage metal-on-semiconductor (LV_MOS) transistors and methods of manufacturing the same are provided. In one embodiment, the method includes implanting ions of a first-type at a first energy level in a drain portion of a first DE_MOS transistor in a DE_MOS region of a substrate to form the first DE_MOS transistor, and implanting ions of the first-type at a second energy level in a LV_MOS region of the substrate adjust a voltage threshold of a first LV_MOS transistor, while concurrently implanting ions of the first-type at the second energy level in the drain portion of the first DE_MOS transistor to form a drain extension of the first DE_MOS transistor. Other embodiments are also provided.

Method of forming drain extended MOS transistors for high voltage circuits

An ESD device that includes a gate and an n-drain region isolated from the gate and formed at least partially within an n-well region, which in turn is formed at least partially within a deep n-well region. The doping levels of the n-drain region, the n-well region and the deep n-well region are in a descending order. The ESD device has trigger and holding voltages, above the operation voltage of its protected circuit, which are layout-configurable by altering the distance between the n-drain and a side edge of the n-well region.

ESD clamp with a layout-alterable trigger voltage and a holding voltage above the supply voltage

A circuit having a high voltage, drain-extended (DE) metal-oxide-semiconductor (MOS) transistor and method for fabricating the same are provided. Generally, the circuit includes an n-channel (NMOS) transistor having: (i) a source and drain formed in a substrate, the source separated from the drain by a channel; and (ii) a diffused deep n-well (DNW) formed by a long, high temperature drive-in step. The DNW forms a drain-extension region for the NMOS transistor surrounding the drain and extending a predetermined distance into the channel. The drain extension region has a doping concentration lower than the source and drain to deplete during reverse biasing of the transistor, thereby raising a breakdown voltage of the transistor. Preferably, the circuit further includes a DE p-channel MOS (PMOS) transistor in which the DNW forms a well tub for the PMOS transistor, and a p-well in DNW forms a DE region therefore. Other embodiments are also disclosed.

CMOS embedded high voltage transistor

Growing community of inventors

Saratoga, CA, United States of America

Sungkwon Lee