Abstract: A conducting trench in a dielectric layer can function as both (a) a plurality of contacts and (b) an interconnect in a semiconductor device. The conducting trench may be made by depositing a conductor in a trough formed in a dielectric layer of the device.
Abstract: A circuit and method for generating a global write enable signal for use in an SRAM partitioning scheme. The global write enable signal is generated by taking a combination of the individual write enable signals and presenting them as a global write control. The global write control signal allows all of the particular data groups to have common timing. The particular SRAM data groups may implement configuration dependent functionality which can be grouped with other data partitions in the array. A particular SRAM data group may share local decode and write control circuitry with other data groups. Particular SRAM data groups not selected for writing have their write data inputs driven to an inactive state during the WRITE.
Type:
Grant
Filed:
November 25, 1996
Date of Patent:
January 12, 1999
Assignee:
Cypress Semiconductor Corp.
Inventors:
George M. Ansel, Andrew L. Hawkins, James E. Kelly
Abstract: The present invention provides a look ahead architecture to satisfy the retransmit recovery time constraints in a mark and retransmit system while allowing a full bitline precharge. A number of sense amplifiers are provided in the look ahead architecture that may be equipped with a "shadow latch" to store the read data when the mark pointer is asserted. As a result, the data to be retransmitted will be retrieved from the shadow latches when the retransmit is asserted, allowing a full precharge cycle before reading from the memory array.
Type:
Grant
Filed:
December 18, 1996
Date of Patent:
January 12, 1999
Assignee:
Cypress Semiconductor Corp.
Inventors:
Pidugu L. Narayana, Daniel Eric Cress, Andrew L. Hawkins, Ping Wu
Abstract: A microprogrammable microprocessor that stores microprogramming instruction sets in a dual ROM configuration enhancing reusability of subroutine operations common between two or more instructions. A first ROM contains a look up table identifying the subroutine(s) utilized by each instruction. The second ROM contains the subroutines needed to implement the required operations for each instruction. The dual ROM microprogrammable microprocessor is used in a Universal Serial Bus microcontroller development system having a microprocessor, control circuit, and an interface to USB bus. The microprocessor system state and I/O registers are mapped to a system bus sharing the same lines with a control circuit. The control circuit provides an RS-232 interface to an attached computing device able to write and read data words to the system bus, thereby to control the microprocessor and associated hardware by setting the system state and writing/reading data from RAM.
Abstract: An associative processing memory system for concurrent data searching and concurrent data processing which includes content addressable memory (CAM) array having multiple CAM words; a multiplexer for executing one of the input devices and for passing an output of one of the input devices; an interface register logic block for storing instructions in a command register and control and status information in a control and status register; a match circuit for executing a match instruction for performing a masked comparison of data in every CAM word in the CAM array to a search pattern; a read circuit for executing a read instruction for reading one CAM word in the CAM array wherein the CAM word is selected using a response register A and a multiple response resolver (MRR); a write circuit for executing a write instruction for performing a masked write operation to every CAM word indicated by a bit set in a select vector; a shift circuit for executing a shift instruction for shifting the response register A up or
Type:
Grant
Filed:
August 1, 1994
Date of Patent:
January 12, 1999
Assignee:
Cypress Semiconductor Corporation
Inventors:
Charles D. Stormon, Edward Saleh, Nikos B. Troullinos, Raymond M. Leong
Abstract: The present invention provides an analog biased pre-driver and pad as well as a duty cycle adjustment cell prior to the pre-driver and pad. The pre-driver and pad may operate in either a 3 volt mode, a 5 volt mode or any voltage in between depending only on the power supply voltage present. No production configuration or post-production configuration is required. The present invention utilizes a special bias circuit to reduce the Vcc, temperature and other processing variations. A duty cycle cell produces a range of duty cycles when the circuit is operating between a 3 volt and 5 volt range.
Abstract: A host bus interface device is provided for interfacing a processor coupled to a host bus to XT/AT legacy I/O devices and a high speed bus. The legacy I/O devices include an interrupt controller, timer/counter and a real time clock. The host bus interface includes a host controller coupled between the host bus and the high speed bus, with the interrupt controller, the timer/counter and the real time clock coupled to the host controller. The host controller is configured to provide an interface between the processor coupled to the host bus and the interrupt controller, the timer/counter, the real time clock device and the high speed bus. The novel host bus interface device has the advantage of improving system performance of an XT/AT compatible personal computer by reducing access latency of the processor to the XT/AT legacy I/O devices.
Abstract: A semiconductor and/or integrated circuit is provided having reduced particulate count upon or within the circuit. During power ramp down post etch or deposition, particles which formed within the plasma used to effectuate etch or deposition are gradually swept from the region above the integrated circuit. Plasma, and more specifically, the field which forms the plasma is maintained but at reduced levels to allow gradual reduction of particles through a multitude of steps. The steps culminate in eliminating power to the electrodes and plasma between the electrodes. However, at the time at which power is absent, only a few of the original particles remain in the critical region above the integrated circuit. Residual particles can be removed in a purge step following the successive sequence of ramp down steps. Gap between the electrodes is increased to a final position early in the ramp down sequence so that additional electrode movement does not occur when the field is weakened.
Abstract: A Static Random Access Memory (SRAM) comprises an input/output pin and driver means connected to the input/output pin. The driver means are configured to drive the input/output pin to a voltage potential using a first current, and are further configured to hold the input/output pin at approximately the voltage potential using a second current. In one embodiment, the driver means may comprise a driver unit for driving the input/output pin to the voltage potential, a bus hold circuit for holding the input/output pin at the voltage potential and a control unit connected to the driver unit and the bus hold circuit. The control unit may activate and deactivate the driver unit and the bus hold circuit.
Type:
Grant
Filed:
June 19, 1997
Date of Patent:
December 22, 1998
Assignee:
Cypress Semiconductor Corporation
Inventors:
Mathew R. Arcoleo, Raymond M. Leong, Derek Johnson, Jonathan F. Churchill
Abstract: A semiconductor structure is provided having an improved oxide with minimal irregularities and charge trap densities. The oxide is formed by an oxidation process which controls temperature and ambient conditions during oxidation as well as prior to and after oxidation. The ambient conditions are chosen such that the silicon surface is more receptive to growing a high quality, relatively thin oxide. A post-oxidation anneal helps ensure any irregularities, dislocations, contaminants involved in trap formation are minimized after the oxide is grown. A post-oxidation anneal involving oxygen incorporated into the oxide is presumed to help minimize any defects which might result from the pre-existing oxidation cycle. A slow ramping of temperature and close control of that temperature helps minimize trap locations at or near the silicon surface on which oxide will be grown.
Abstract: The present invention provides a circuit for generating a programmable write-read word line equality signal in FIFO buffers. The present invention significantly reduces the gate delay associated in producing the write-read word line equality signal. The delay is reduced from a typical 30-50 gate delays, to as little as four gate delays. The present invention accomplishes this by processing several bit operations in parallel and making the general circuit architecture symmetric. The delay is constant in all of the parallel paths but amounts to only a short delay for the final WREQ output.
Type:
Grant
Filed:
December 29, 1995
Date of Patent:
December 22, 1998
Assignee:
Cypress Semiconductor Corp.
Inventors:
Andrew L. Hawkins, Pidugu L. Narayana, Roland T. Knaack
Abstract: A method for forming a gap in a silicon layer is described. A silicon layer is formed over a substrate. A nitride layer is formed over the silicon layer and an oxide layer is formed over the silicon layer, adjacent to the nitride layer. A portion of the oxide layer is then removed to form an exposed region of the silicon layer. Then an etchant is applied to the exposed region to form an gap of the silicon layer.
Abstract: The present invention provides an efficient design that can be used to generate a programmable almost empty or programmable almost full flags. The present invention accomplishes this by efficiently evaluating the read count minus write count plus a user programmed offset being greater than or equal to zero for the programmable almost empty flag generation. Similarly, evaluating write count minus the read count plus the user programmed offset minus the size of the FIFO is greater than or equal to zero for the programmable almost full flag generation. The counters in the FIFO count from 0 to twice the size of the FIFO minus one and the user programmed offset can be between 0 to the size of the FIFO minus one. The offset has one less bit than the read and write counters. The processing block masks out the higher order bits of the Offset input based on the size of the FIFO. The first stage performs the bit wise addition of the offset, read counter and write counter inputs without any carry chain propagation.
Abstract: An interruptible state machine includes a state machine and an interrupt processor. The interrupt processor minimizes the required total number of states for the state machine when it must return to its next "normal" state after an input or interrupt that may occur at any of its normal states. In response to the interrupt, the interrupt processor stores the next state, processes the interrupt, and restores the next state after processing the interrupt.
Abstract: The macrocell is configured to allow a single register to be employed either as a register for storing internal macrocell product terms (or logical combinatorial thereof) or as an input register for directly storing signals received from an input/output pin. One embodiment of the macrocell, described herein, includes the register and the input/output pin, along with three two-to-one multiplexers and an output enable logic unit. Feedback lines are also provided. The components are interconnected and appropriate multiplexer and output enable selection signals are provided to allow the macrocell to input and output a variety of combinations of signals including combinatorial and registered logic signals, buried combinatorial and buried registered logic signals, and input and output signals.
Type:
Grant
Filed:
December 26, 1995
Date of Patent:
December 8, 1998
Assignee:
Cypress Semiconductor Corporation
Inventors:
Richard L. Kapusta, Christopher W. Jones
Abstract: Methods for designing a programmable interconnect matrix having reduced connectivity to achieve maximum routability for the reduced connectivity. An array of multiplexors, each having a multiplexor width w.sub.mux that is less than number of input conductors for the programmable matrix, are coupled to the input conductors of the programmable interconnect matrix such that the number of input signals shared between any two multiplexors is less than the multiplexor width w.sub.mux and such that each input signal has approximately the same number of chances to route. To better ensure the successful routing of input signals by a programmable interconnect matrix designed according to the present methods, improved routing methods are also described. According to a first embodiment, routing is accomplished by swapping successfully routed input signals with a blocked input signal and determining whether the input signal that has been swapped out may be routed through available multiplexors.
Type:
Grant
Filed:
August 30, 1996
Date of Patent:
December 8, 1998
Assignee:
Cypress Semiconductor Corp.
Inventors:
Hagop A. Nazarian, Stephen M. Douglass, W. Alfred Graf, S. Babar Raza, Sundar Rajan, Shiva Sorooshian Borzin, Darren Neuman
Abstract: An internal clock signal disable circuit is disclosed for disabling an internal clock signal used in a synchronous static random access memory (SRAM). The reduced power mode is preferably a sleep mode commanded by assertion of a reduced power command signal, which may be a Jedec-standard "ZZ" signal. The disable circuit includes a pair of latch devices clocked by clock signals deriving from the external clock signal applied to the SRAM. The ZZ signal is applied to the input of the first latch, whose output is connected to the input of the second latch. The output of the second latch is processed to generate disable signals for disabling generation of the internal clock signal used on the device. The pair of latches insures that a delay is introduced prior to disabling the internal clock so that at least one clock pulse of the internal clock signal is generated before the internal clock is shut down.
Abstract: An anchor structure placed in an open field in corner areas of the semiconductor die and along die edges for preventing cracks in the die. In the corner areas, the anchor structure is placed perpendicular to a resultant vector force, which is approximately at a 45.degree. angle to an imaginary horizontal line passing through the die. This perpendicular placement of the anchor structure more uniformly distributes the stresses along the anchor preventing corner cracks in the die. Along the die edges, the anchor structures are placed approximately perpendicular to the resultant vector forces that impinge the die edges.
Abstract: A circuit for measuring the frequency difference between a reference clock and a second clock. The circuit presents a first output in response to a phase crossing between the two clocks. A second circuit presents a second output in response to the first output and the reference clock.
Abstract: The invention concerns an asynchronous state machine with a programmable tSKEW which may be used to generate a half-empty and half-full flags in a synchronous FIFO buffer. The present invention may reduce the delay associated in producing the half-full or half-empty flags from a typical eight gate delays, to as little as no gate delays. The reduction may be accomplished by using a first state machine which can make an internal flag go low, or active, and a second state machine which can make the internal flag go high, or inactive. The functioning of the first and second state machines may be controlled by a blocking logic. The output of each of the state machines may be stored in a latch. The output of the latch may be presented to an input of the blocking logic, which may be used by the blocking logic to control the activity of the state machines.