Micron Technology Incorporated

Micron Display Technology, Inc.

Tom W Voshell

Jake Baker

Glen F Hush

Mirmajid Seyyedy

Glen Earl Hush

A circuit and method for producing a walking one pattern in a shift register. The circuit comprises a shift register and a NOR gate. The NOR gate output is connected to the data input of the shift register, and the data output of each of said register stages is connected to a respective one of the NOR gate inputs.

Producing walking one pattern in shift register

A method and apparatus for selecting a rowline in a MRAM device. A rowline select circuit is provided on a first side of each rowline and connects the rowline to ground when a memory cell in the rowline is being written to and to a voltage source when a memory cell in the rowline is being read. A rowline stack select circuit is provided on the second side of each rowline and is connected to one rowline on each plane of memory. When a memory cell is being accessed, the rowline containing that memory cell as well as each other rowline connected to the same rowline stack select circuit are connected to a current source.

Single ended row select for a MRAM device

A programmable output driver is comprised of a first signal path for pulling an output node up to a first voltage level and a second signal path for pulling the output node down to a second voltage level. A plurality of capacitors and a plurality of switches are provided for programmably connecting certain of the plurality of capacitors to the second signal path to control the falling edge of a signal output from the driver. In a preferred embodiment, the first signal path includes a boot circuit which primarily controls the leading edge of the signal output from the driver. A method of operating an output driver is also disclosed.

Output driver having a programmable edge rate

A matrix display maintains synchronization with an input NTSC composite video signal by combining the functions of a phase locked loop, a column selector, and a row selector. The matrix includes display cells arranged in rows and columns, each display cell enabled for display on receipt of a column pointer signal and a row pointer signal. The column selector includes a shift circuit that shifts a walking-one pattern to assert in turn one column pointer signal at a time for each column in the matrix. An overflow signal from the shift circuit is used for three functions: (1) to reinstate the walking pattern in the column selector, (2) to lock the phase locked loop on the horizontal synchronization pulse of the NTSC signal, (3) to clock the row selector. The row selector includes a shift circuit and walking-one pattern to assert in turn one row pointer signal for each row of the matrix. Vertical synchronization is maintained by recording several samples of the NTSC signal taken after successive horizontal synchronization pulses, and selectively disabling the phase comparator of the phase locked loop. In a preferred embodiment, the matrix display includes field emission display cells arranged with all support circuitry on an integrated circuit substrate. Shift circuits, consisting of low power dynamic shift stages, eliminate conventional counter circuitry saving surface area on the substrate and reducing heat and power consumption.

Timing control for a matrixed scanned array

A serial to parallel conversion circuit uses a dynamic shift register in a phase locked loop for an index to access a parallel holding register. The composite input signal includes serial data to be sampled and a synchronizing signal at an integer factor of the sampling serial data rate. The phase locked loop generates a control signal for sampling the serial data at a multiple of the synchronizing frequency by incorporating a delay between a variable frequency oscillator output and a phase comparator input. The delay element in one embodiment includes a shift register with a walking-one pattern that overflows to the phase comparator. The walking-one pattern is used to identify which position of the holding register should store the next sample of the input signal. The shift register is self-initialized by a logic combination of all shift register outputs. Power dissipation by the serial to parallel conversion circuit is minimal because only one 7-transistor shift register cell draws current at a time.

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Boise, ID, United States of America

Tom W Voshell