Silicon Storage Technology, Inc.

Kai Man Yue

Xiaozhou Qian

Bomy A Chen

Yao Zhou

Xiao Yan Pi

Ning Bai

Nhan Do

Dana Lee

Jinho Kim

Feng Gao

Qing Rao

Hieu Van Tran

Vipin Tiwari

Xian Liu

Douglas J Lee

Jack Frayer

Yuri Tkachev

Bin Sheng

Parviz Ghazavi

Tsung-Lu Syu

Guangming Lin

Yaohua Zhu

Xiaozhou Qiang

Li Fang Bian

Lisa Bian

Geeng Chuan Michael Chern

Andrew Chen

Guang Yan Luo

A method and apparatus are disclosed for reducing the coupling that otherwise can arise between word lines and control gate lines in a flash memory system due to parasitic capacitance and parasitic resistance. The flash memory system comprises an array of flash memory cells organized into rows and columns, where each row is coupled to a word line and a control gate line.

Method and apparatus for reducing coupling between word lines and control gate lines in a flash memory system

An improved low-power sense amplifier for use in a flash memory system is disclosed. The reference bit line and selected bit line are pre-charged during a limited period and with limited power consumed. The pre-charge circuit can be trimmed during a configuration process to further optimize power consumption during the pre-charge operation.

Sense amplifier for a flash memory system

Multiple embodiments of a low power sense amplifier for use in a flash memory system are disclosed. In some embodiments, the loading on a sense amplifier can be adjusted by selectively attaching one or more bit lines to the sense amplifier, where the one or more bit lines each is coupled to an extraneous memory cell.

Low power sense amplifier for a flash memory system

An improved sensing circuit is disclosed that utilizes a bit line in an unused memory array to provide reference values to compare against selected cells in another memory array. A circuit that can perform a self-test for identifying bit lines with leakage currents about an acceptable threshold also is disclosed.

High speed and low power sense amplifier

A system and method to inhibit the erasing of a portion of a sector of split gate flash memory cells while allowing the remainder of the sector to be erased is disclosed. The inhibiting is controlled by control logic that applies one or more bias voltages to the portion of the sector whose erasure is to be inhibited.

System and method to inhibit erasing of portion of sector of split gate flash memory cells

A self-timer for a sense amplifier in a memory device is disclosed.

Self-timer for sense amplifier in memory device

A memory device that includes a plurality of ROM cells each having spaced apart source and drain regions formed in a substrate with a channel region therebetween, a first gate disposed over and insulated from a first portion of the channel region, a second gate disposed over and insulated from a second portion of the channel region, and a conductive line extending over the plurality of ROM cells. The conductive line is electrically coupled to the drain regions of a first subgroup of the ROM cells, and is not electrically coupled to the drain regions of a second subgroup of the ROM cells. Alternately, a first subgroup of the ROM cells each includes a higher voltage threshold implant region in the channel region, whereas a second subgroup of the ROM cells each lack any higher voltage threshold implant region in the channel region.

Array of non-volatile memory cells with ROM cells

The present invention relates to a flash memory device that uses dummy memory cells as source line pull down circuits. In one embodiment, when a memory cell is in read mode or erase mode, its source line is coupled to ground through a bitline of a dummy memory cell, which in turn is coupled to ground. When the memory cell is in program mode, the bitline of the dummy memory cell is coupled to an inhibit voltage, which places the dummy memory cell in a program inhibit mode that maintains the dummy memory cell in erased state.

Flash memory system using memory cell as source line pull down circuit

A trimmable current reference generator for use in a sense amplifier is disclosed.

Trimmable reference generator for sense amplifier

The present invention is a storage element for controlling a logic circuit and a logic device having a plurality of storage elements. The storage element has a first and a second non-volatile memory cells connected in series at an output node. Each of the first and second non-volatile memory cells is for storing a state opposite to the other. A demultiplexer has an input, a switched input and two outputs. The output node is connected to the input of the demultiplexer. One of the outputs is used to control the logic circuit. The other output is connected to a bit line which is connected to a sense amplifier. Finally, the switched input receives a switch signal and outputs the signal from the output node to either the one output or the other output.

Storage element for controlling a logic circuit, and a logic device having an array of such storage elements

A array of multi-bit Read Only Memory (ROM) cells is in a semiconductor substrate of a first conductivity type with a first concentration. Each ROM cell has a first and second regions of a second conductivity type spaced apart from one another in the substrate. A channel is between the first and second regions. The channel has three portions, a first portion, a second portion and a third portion. A gate is spaced apart and is insulated from at least the second portion of the channel. Each ROM cell has one of a plurality of N possible states, where N is greater than 2. The state of each ROM cell is determined by the existence or absence of extensions or halos that are formed in the first portion of the channel and adjacent to the first region and/or in the third portion of the channel adjacent to the second region. These extensions and halos are formed at the same time that extensions or halos are formed in MOS transistors in other parts of the integrated circuit device, thereby reducing cost. The array of ROM cells are arranged in a plurality of rows and columns, with ROM cells in the same row having their gates connected together. ROM cells in the same column have the first regions connected in a common first column, and second regions connected in common second column. Finally, ROM cells in adjacent columns to one side share a common first column, and cells in adjacent columns to another side share a common second column.

Multi-bit ROM cell, for storing one of n&#x3e;4 possible states and having bi-directional read, an array of such cells, and a method for making the array

Multi-bit ROM cell, for storing on of N&#x3e;4 possible states and having bi-directional read, an array of such cells

A multi-bit Read Only Memory (ROM) cell has a semiconductor substrate of a first conductivity type with a first concentration. A first and second regions of a second conductivity type spaced apart from one another are in the substrate. A channel is between the first and second regions. The channel has three portions, a first portion, a second portion and a third portion. A gate is spaced apart and is insulated from at least the second portion of the channel. The ROM cell has one of a plurality of N possible states, where N is greater than 2. The possible states of the ROM cell are determined by the existence or absence of extensions or halos that are formed in the first portion of the channel and adjacent to the first region and/or in the third portion of the channel adjacent to the second region. These extensions and halos are formed at the same time that extensions or halos are formed in MOS transistors in other parts of the integrated circuit device, thereby reducing cost.

Multi-bit ROM cell with bi-directional read and a method for making thereof

A nonvolatile reprogrammable switch for use in a PLD or FPGA has a nonvolatile memory cell connected to the gate of an MOS transistor with the terminals of the MOS transistor connected to the source of the signal and to the circuit. The nonvolatile memory cell is of a split gate type having a first region and a second region, with a channel therebetween. The cell has a floating gate positioned over a first portion of the channel, which is adjacent to the first region and a control gate positioned over a second portion of the channel, which is adjacent to the second region. The second region is connected to the gate of the MOS transistor. The cell is programmed by injecting electrons from the channel onto the floating gate by hot electron injection mechanism. The cell is erased by Fowler-Nordheim tunneling of the electrons from the floating gate to the control gate. As a result, no high voltage is ever applied to the second region during program or erase. In addition a MOS FET transistor connects the gate of the MOS transistor to a voltage when the non-volatile memory cell is turned off. The floating gate of the non-volatile memory cell is connected to the gate of the MOS FET transistor.

Integrated circuit with a three transistor reprogrammable nonvolatile switch for selectively connecting a source for a signal to a circuit

A nonvolatile reprogrammable switch for use in a PLD or FPGA has a nonvolatile memory cell connected to the gate of an MOS transistor with the terminals of the MOS transistor connected to the source of the signal and to the circuit. The nonvolatile memory cell is of a split gate type having a floating gate positioned over a first portion of the channel and a control gate positioned over a second portion of the channel with electrons being injected onto the floating gate by hot electron injection mechanism. The nonvolatile memory cell is erased by the action of the electrons from the floating gate being tunneled through Fowler-Nordheim tunneling onto the control gate, which is adjacent to the second region. As a result, no high voltage is ever applied to the second region during program or erase. Thus, the nonvolatile memory cell with the second region can be connected directly to the gate of the MOS transistor, which together therewith forms a nonvolatile reprogrammable switch.

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Shanghai, China

Kai Man Yue