摘要:
In a SRAM structure, power consumption is reduced by providing a structure which allows specific memory cells to be selected using word lines and column select lines, and reducing the load on the column address lines by dividing the load into sectors. The dividing into sectors is achieved by making use of sector select lines for selecting two or more rows of cells, and logically ANDing the sector select lines with the column select lines.
摘要:
A SRAM system which provides for reduced power consumption. The SRAM system utilizes an array of bit cells. Columns of bit cells in the array are partitioned into sections. Each section of bit cells shares a local bit line. A sector select circuit provides for precharging the local bit lines. The sector select circuit also includes a mux for connecting a local bit line to a global bit line. The sector select circuit includes a device for detecting when a sector select signal and a column select signal are present. When both of these signals are present the sector select circuit couples the local bit line with the global bit line, and disengages the precharging of the local bit line.
摘要:
A split-gate flash memory array is programmed, in part, by applying a programming voltage to the row of cells that include the to-be-programmed cells, and an inhibiting voltage to the row of cells that share the same source line as the row that includes the to-be-programmed cells. The inhibiting voltage is greater than zero and less than the programming voltage.
摘要:
The potential on a pixel cell having a gated diode and a read out transistor is set to an initial level prior to an image integration period. During the image integration period, absorbed photons cause the potential on the pixel cell to change. After the image integration period, the pixel cell is then reset and read out by applying a number of pulses to the gated diode. Each of the pulses causes a fixed amount of charge to be injected into the cell. When the potential on the cell has again returned to the initial level, the number of absorbed photons is determined by counting the number of pulses that were required to return the potential to the initial level. The read out transistor is used to determine when the potential is at the initial level by biasing the transistor to output a current that corresponds to the potential on the pixel cell.
摘要:
A sense amplifier places a low positive voltage, such as 0.1 to 0.3 volts, on a bit line instead of ground when a memory cell is read by utilizing a current source circuit to output a reference current that biases a Schottky diode. The current source circuit is implemented with a Schottky diode that utilizes the reverse-biased leakage current of the diode to form the reference current. The current source circuit can also be implemented with a current mirror circuit.
摘要:
An ESD protection device for use with an integrated circuit that provides a low impedance resistive path between IC pads (including Vdd and Vss pads) when power to the IC is off, while assuring adequate isolation between the IC pads when the power is on. The device includes a semiconductor substrate (typically a p-type Si substrate) and at least two vertically integrated pinch resistors formed in the semiconductor substrate. Each of the vertically integrated pinch resistors is connected to a common electrical discharge line and to a pad. Each of the vertically integrated pinch resistors includes a deep well region and a first surface well region, both of the second conductivity type (typically n-type). The first surface well region circumscribes the deep well region, thereby forming a narrow channel region of the first conductivity type (e.g. p-type) therebetween. When no potential is applied to the first surface well regions (i.e. power is off), the two vertically integrated pinch resistors connected by the common electrical discharge line provide a low impedance resistive path between the pads for shunting ESD current. When a potential is applied to the first surface well region by the IC power supply (i.e. power is on), however, the width of the narrow channel region is pinched-off due to a potential-produced depletion region in the narrow channel region, thereby isolating the pads from each other. A process for the formation of the ESD protection device involves sequential formation of each of the device regions in a semiconductor substrate.
摘要:
An analog circuit starter current source device with automatic shut-down capability. The device includes a semiconductor substrate (typically p-type) with a deep well region (typically n-type) below its surface, a first surface well region (typically n-type) on the surface of the substrate that circumscribes the deep well region, and a narrow channel region (typically p-type) separating the deep well region from the first surface well region. The device also includes a first contact region for connecting the first surface well region to the analog circuit, and a second contact region for connecting a substrate region above the deep well to the analog circuit. The configuration provides a variable-width vertical resistor current path capable of starting an analog circuit and then being automatically shut-down by application of a potential to the first contact region sufficient to produce a depletion region that pinches-off the narrow channel region. A process for forming the starter current source device is also provided. The process includes first providing a semiconductor substrate (e.g. p-type), then forming a deep well region (e.g. n-type) below its surface. This is followed by the formation of a first surface well region (e.g. n-type) on the surface of the substrate such that the first surface well region circumscribes the deep well region, thereby producing a narrow channel (e.g. p-type) therebetween. Finally, a first contact region is formed on the surface of the first surface well region, while a second contact region is formed on the surface of semiconductor substrate above the deep well region.
摘要:
A non-volatile memory (NVM) cell structure comprises a PMOS program transistor having source, drain and bulk region electrodes and a gate electrode that is connected to a data storage node; an NMOS control transistor having source, drain and bulk region electrodes that are commonly-connected to receive a control voltage and a gate electrode that is connected to the data storage node; a PMOS erase transistor having source, drain and bulk region electrodes that are commonly-connected to receive an erase voltage and a gate electrode that is connected to the data storage node; and an NMOS read transistor having source, drain and bulk region electrodes and a gate electrode connected to the data storage node.
摘要:
A non-volatile memory (NVM) cell structure comprises an NMOS control transistor having source, drain and bulk region electrodes that are commonly-connected to receive a control voltage and a gate electrode that is connected to a data storage node; a PMOS erase transistor having source, drain and bulk region electrodes that are commonly-connected to receive an erase voltage and a gate electrode that is connected to the data storage node; and an NMOS data transistor having source, drain and bulk region electrodes and a gate electrode connected to the data storage node.
摘要:
A 4-transistor non-volatile memory (NVM) cell includes a static random access memory (SRAM) cell structure. The NVM cell utilizes a reverse Fowler-Nordheim tunneling programming technique that, in combination with the SRAM cell structure, allows an entire array to be programmed at one cycle. Equalize transistors are utilized to obtain more uniform voltage on the floating gates after an erase operation. Utilization of decoupling pas gates during a read operation results in more charge difference on floating gates of programmed and erased cells.