Intel Corporation

Alan E Baker

Jerry A Kreifels

Steven E Wells

Rodney R Rozman

Peter K Hazen

Virgil N Kynett

Charles W Brown

Christopher John Haid

Mark D Winston

Vishram P Dalvi

David A Leak

Thomas C Price

George Hoekstra

Fasil G Bekele

Albert Fazio

Gregory E Atwood

Neal R Mielke

Owen W Jungroth

Richard J Durante

Jerry G Jex

Chih-Ta Sung

Steve Wells

A method and apparatus suspend a program operation in a nonvolatile writeable memory. The nonvolatile writeable memory includes a memory array, a command register and memory array control circuitry. The command register decodes a program suspend command and provides a suspend signal as an output. The memory array control circuitry is coupled to receive the suspend signal from the command register. The memory array control circuitry performs a program operation in which data is written to the memory array. The memory array control circuitry suspends the program operation upon receiving the suspend signal.

Nonvolatile writeable memory with program suspend command

A method and apparatus suspend a program operation in a nonvolatile writeable memory. The nonvolatile writeable memory includes a memory array, a command register, and memory array control circuitry. The command register decodes a program suspend command and provides a suspend signal as an output. The memory array control circuitry is coupled to receive the suspend signal from the command register. The memory array control circuitry performs a program operation in which data is written to the memory array. The memory array control circuitry suspends the program operation upon receiving the suspend signal.

Method and apparatus for suspending the writing of a nonvolatile

Circuitry for locking out a first signal generated from a first power supply while the first power supply is at or below a first voltage level is described for a non-volatile semiconductor memory. The circuitry includes a first P-type transistor P1 having a gate, a drain, and a source. The source of P1 is coupled to a second power supply, the drain of P1 is coupled to a first node and the gate of P1 is coupled to a second node. The second node provides an output signal representative of the first control signal. The circuitry also includes a first N-type transistor N1, having a gate, a drain, and a source. The drain of N1 is coupled to the first node, the source of N1 is coupled to a third, and the gate of N1 is coupled to the first control signal and to a fourth node. Included is a second N-type transistor N2, having a drain, a source and a gate. The gate of N2 is coupled a sixth node. The drain of N2 is coupled to the second node and the source of N2 is coupled to the third node. A second P-type transistor is included in the circuitry and also has a gate, a drain and a source. The source of P2 is coupled to the second power supply, the gate of P2 is coupled to the first node and a drain of P2 is coupled to second node. Also included in this circuitry is a third N-type transistor N3 having a gate, a drain, and a source. The drain of the N3 transistor is coupled to the first node, the source of N3 is coupled to the third node and the gate of N3 is coupled to a fifth node. The circuitry includes apparatus for preventing transistor N2 from driving the second node when the first power supply is below the first voltage level. The output of the apparatus is coupled to the gate of N2. The apparatus inputs are coupled to the first control signal and a second control signal representative of the voltage level of said first power supply.

High voltage level converter

A low power bias voltage generation circuitry for content addressable memory cells for a nonvolatile memory is described. The bias circuitry is comprised of a source follower pair and two cascaded high impedance voltage dividers. The source follower pair acts as a positive feedback loop coupling between the two high impedance voltage dividers for relatively quickly charging and settling the output node to a predetermined voltage level. The first high impedance voltage divider can relatively quickly provide an input signal to trigger the small-input-load second high impedance voltage divider. The second high impedance voltage divider comprised of two high impedance diode stacks allows most current drawing from the power supply to drive a relatively large output loading during switching. Both first and second high impedance voltage dividers help keep the DC current of the circuit to a relatively low level which helps to reduce the total power consumption of the circuit.

Bias circuitry for content addressable memory cells of a floating gate

A non-volatile memory device is described. The memory device includes a global bit line, a first block, and a second block. The first block includes a first memory cell having a drain region, a source region, a floating gate and a control gate. A first word line is coupled to the control gate of the first memory cell. A first local bit line is coupled to the drain region of the first memory cell. A first selecting means couples the first local bit line to the global bit line. The second block includes a second memory cell having a drain region, a source region, a floating gate and a control gate. A second word line is coupled to the control gate of the second memory cell. A second local bit line is coupled to the drain region of the second memory cell. A second selecting means couples the second local bit line to the global bit line.

Floating gate non-volatile memory blocks and select transistors

A semiconductor flash EPROM/EEPROM device which includes a command port controller for receiving command instructions from a data bus coupled to the memory device. Instruction words to a command port controller operates to instruct the device to perform read, erase, program, or verify functions and the command port controller generates necessary control signals to cause the memory to function appropriately. By utilizing the command port controller the memory device can be erased and programmed while the device is in the circuit and permits pin compatibility with the prior art EPROM and EEPROMs.

Processor controlled command port architecture for flash memory

A semiconductor flash EPROM/EEPROM device which includes a command port for receiving instruction on a data line and providing control signals to a memory for providing program and erase functions, a method to program and erase the memory. A program sequence is comprised of setting up a program command during a first write cycle, preforming a second write cycle to load address to address register and data to to a data register, programming during a program cycle and writing a program verify command during a third write cycle to verify the programmed data during a read cycle. An erase sequence is comprised of writing a setup erase command during a first write cycle, an erase command during a second write cycle providing the erasure during an erase cycle, writing the erase verify command during a third write cycle which also addresses the address of the memory and providing erase verification during a read cycle. Both the erase and program cycles provide for measured incremental erasing and programming.

Program/erase selection for flash memory

A circuit is disclosed for preventing the erasing and programming of a nonvolatile memory device during power up and power down transitions. A power supply generator incorporating an n-channel device and a w-channel device in a wired-or configuration is coupled to a programming voltage Vpp and to a circuit voltage Vcc, and generates a node voltage Vpwr which is the greater of Vpp-Vtn and Vcc-Vtw. Vtn is the gate threshold voltage of the n-channel device, while Vtw is the gate threshold voltage of the w-channel device. The node voltage Vpwr is coupled to a reference voltage generator which provides a reference voltage, a protecting voltage, and a biasing voltage for a Vcc comparator and a Vpp comparator. The Vcc comparator and the Vpp comparator compare Vref with the output of a Vcc divide-by-two circuit and a Vpp divide-by-five cirucit, respectively. Thus, during the power up transition of the nonvolatile memory device where over-erasing may damage the memory array, the circuit forces the nonvolatile memory device into read mode, ensuring that no damaging voltage reaches the memory array. During the power down transition of a nonvolatile memory device where over-programming may accidentally erase the content of the memory array, the circuit forces the nonvolatile memory device into read mode, ensuring that the nonvolatile memory is always in a known state, and thus one can read the memory array. As such, the use of the preferred embodiment of the present invention obviates the prior art power up and power down sequencing and also affords greater protection against accidental erasure and programming than the prior art lockout detection circuit.

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Fair Oaks, CA, United States of America

Alan E Baker