Abstract: A programmable I/O cell with a multiplicity of configurations and data conversion options implemented through the use of antifuses. Increased logic utilization and reduced number of components necessary to implement such designs by using the registers in the I/O cell to implement data conversion functions thereby saving the logic and registers of the FPGA logic cells for implementation of other functions is achieved. Serial-to-parallel and parallel-to-serial data conversion operations utilize adjacent registers in adjacent cells to perform shift operations.

Abstract: The burst mode memory architecture using interleaved memory arrays provides even and odd EPROM arrays with data having even addresses stored in the even array and data having odd addresses stored in the odd array. A control circuit receives an initial address from a memory system controller and then accesses all data from the even and odd arrays within a burst address space containing the initial address. A pair of out-of-phase counters generate even and odd addresses, respectively, for accessing the even and odd arrays. Each counter increments addresses sequentially until a burst address space boundary is reached, then the counters wrap around to a beginning of a burst address space to generate any remaining addresses within a burst address space. The burst mode control circuitry is capable of processing a variety of burst sequencing modes. The burst address space size and the burst sequencing mode are selectable.

Abstract: An extender circuit provides a serial communication interface between an ATM layer and a PHY layer. The extender circuit includes a first circuit serially coupled to a second circuit. The first circuit is coupled to the ATM layer and communicates in parallel with the ATM layer. The first circuit is operable to receive a control signal from the ATM layer. The second circuit is coupled to the PHY layer and communicates in parallel with the PHY layer. The first circuit does not transmit the control signal to the second circuit. The second circuit regenerates the control signal at the PHY layer. The first circuit and the second circuit function in like manners. The first circuit receives a control signal generated by the ATM layer. The control signal may comprise a start of cell signal. The first circuit transmits a first sequence of signals to the second circuit.

Abstract: A protective circuit for protecting internal circuits of semiconductor integrated circuits (ICs) from ElectroStatic Discharges (ESD) into a voltage conduit of a semiconductor IC. The protective circuit is coupled in parallel with the internal circuit of the semiconductor IC such that the protective circuit and the internal circuit are each coupled to a first voltage conduit at a first reference voltage at one end and to a second voltage conduit at a second reference voltage at another end. The protective circuit includes an ESD protection device (or devices) for channeling an ESD discharge from the first voltage conduit through the protective circuit to the second voltage conduit. The protective circuit also includes a control circuit for turning "on" (e.g. operating in a low impedance state) the ESD protection device during the occurrence of the ESD discharge into the first voltage conduit.

Abstract: The presently preferred embodiment of the invention provides a memory structure that eliminates the thick gate associated with the offset of the FAMOS transistor and reduces the standard 225 angstrom offset to a 100 angstrom offset required for FN tunnelling. The 100 angstrom offset is realized uniformly underneath the entire area of the floating poly. The invention uses transistors each having a 100 angstrom offset to realize both erase and programming functions. The present invention realizes an erasing feature through an erase transistor and an ERL line. However, the programming of the cell will be realized through the programming transistor. As a result, a double poly flash cell will function like an EEPROM. This functioning eliminates the hot electron tunnelling required to program conventional double poly flash cells and results in a significant reduction in chip real estate. The reduction allows the present invention to be scaled to next generation architectures.

Abstract: A memory system includes a main memory and a memory controller, the main memory including at least one block which has a plurality of banks. The memory controller includes a plurality of data channels each of which can access at least one bank in the main memory. Each data channel comprises a write first-in-first-out (FIFO) buffer for efficiently supporting cache purge operations and normal write operations, and a reflective write FIFO buffer for efficiently supporting coherent read with simultaneous cache copyback operations. The memory controller selects the proper FIFO or FIFOs depending on the type of data transaction, and selects the proper channel or channels depending on the system bus size, the data transaction size, and the status of cache FIFO(s). The memory system can efficiently support data transactions having different data lengths or sizes from a byte to a long burst. The memory system can support different bus and processor systems and different data transactions in a highly efficient manner.

Abstract: An output buffer having a reduced-swing output includes a p-channel pullup transistor as the primary pullup device. A biasing circuit is provided so as to bias the gate terminal of the pullup p-channel transistor to a predetermined level. The predetermined level is effective to cause the p-channel pullup transistor to shut off when the output of the buffer reaches a reduced magnitude output level (V.sub.OH). In the disclosed embodiment, the biasing circuit includes an n-channel transistor connected between the gate and drain terminals of the p-channel pullup transistor. The biasing circuit also includes a p-channel transistor having a source terminal connected to V.sub.cc, and a drain terminal connected to the gate of the pullup transistor. When the output of the buffer is desired to be in a logic high state, both of the biasing transistors are "ON.

Abstract: A bit line driver circuit includes a first driver and a second driver. The first driver drives a bit line when the bit line driver is in a first state. The second driver drives the bit line when the bit line driver is in a second state. The first driver is configured to produce a slow slew rate for the bit line and the second driver is configured to produce a faster slew rate for the bit line. The first and second drivers may include a first and second pair of driver transistors which are each coupled to the bit line. The states of the bit line driver circuit may be defined by instruction signals applied to the driver circuit and the driver circuit includes decoder logic to interface the instruction to the first and second pairs of driver transistors.

Abstract: An internal tri-state bus is provided in a field programmable gate array (FPGA). The FPGA is comprised of an input/output interface which receives input data and generates output data. User-configurable logic cells are included within the FPGA and are coupled to the input/output interface through interconnect elements. The interconnect elements provide a number of conductive elements which supply input signals to the logic cells and receive output signals generated by the logic cells. At least one of the logic cells contains at least one output and multiple logic elements which typically include AND gates, multiplexers and registers. The logic elements receive input signals from the interconnect elements, perform digital functions on the input signals and generate output signals to the interconnect elements. At least one logic cell in the FPGA contains a tri-state buffer which is coupled to at least one output of the logic cell.

Abstract: The present invention concerns a method and apparatus for generating a global wordline signal without requiring a metal layer for the global wordline route across multiple arrays. The global wordline signal is generally cascaded between the various group arrays. A low voltage level is generally presented across the wordlines to the various arrays that are inactive to minimize the overall amount of current used by the circuit. Once a particular array is activated, the present invention boosts the signal to a high level which represents an active wordline for a selected array. The present invention uses a global wordline scheme that uses the local wordlines from the previous array to determine whether to bring the next array up to an active level.

Abstract: A method and system for removing an 8-inch semiconductor wafer from a final polishing pad of a Chemical Mechanical Polishing machine is disclosed. The polishing machine includes a rotating platen, and a polishing pad affixed thereto for rotation therewith. Moreover, the machine includes a generally-cylindrical carrier portion rotatable about an axis of rotation for receiving and retaining the semiconductor wafer. During normal operation, the platen and carrier both rotate about their respective axes of rotation, while, in addition, the carrier is oscillated by a mechanical arm along the surface of the polishing pad in a substantially radial path, relative to the axis of the platen. Prior to removing the wafer, the platen and carrier rotation is discontinued, while the radial movement of the carrier is allowed to continue for predetermined number of oscillations during a predetermined time to thereby dissipate adhesion forces inhibiting removal of the wafer.

Abstract: A synchronous contention prevention circuit for a bi-directional bus. The synchronous contention prevention circuit comprises a synchronous anticontention circuit coupled to a first input/output circuit. The synchronous anticontention circuit receives a driver select signal and a clock signal. The first input/output circuit has a first input coupled to the synchronous anticontention circuit and a first output. When the driver select signal is in a first logic state, the first input/output circuit is disabled from driving the first output. Subsequently, the driver select signal transitions from the first logic state to a second logic state. After the driver select signal transition to the second logic state, the synchronous anticontention circuit generates a first signal in response to a first transition of the clock signal. The synchronous anticontention circuit then generates a second signal in response to the first signal and a second transition of the clock signal.

Abstract: A multi-port memory device comprising a memory cell coupled to a first port and a second port. The second port receives write data for writing into the memory cell. The multi-port memory device further comprises an undo circuit coupled to the memory cell. The undo circuit invalidates the write data in response to receiving a busy signal. When the undo circuit invalidates the write data, the write data is not written into the memory cell. The busy signal indicates that the first port is enabled to access the memory cell at substantially the same time that the second port receives the write data. The busy signal may be generated by arbitration circuitry in the multi-port memory device or by arbitration circuitry in another device coupled to the multi-port memory device. For one embodiment, the busy signal may be generated by arbitration circuitry in a second multi-port memory device coupled in width expansion with the first multi-port memory device.

Abstract: A FIFO (First-In-First-Out) memory includes a main memory array and a main select circuit having a plurality of serially coupled shift registers, each selecting at least one memory location of the main memory array. The FIFO memory also includes a redundant memory array and a redundant select circuit having a plurality of redundant shift registers, each selecting at least one redundant memory location of the redundant memory array. A switching circuit is provided in the FIFO memory that is coupled to each of the shift registers and each of the redundant shift registers. When a memory location of the main memory is found defective, the switching circuit causes a corresponding shift register of the shift registers to be bypassed in the main select circuit and a redundant shift register of the redundant shift registers to be serially coupled into the main select circuit via a last one of the shift registers.

Abstract: A non-linear integrated phase locked loop circuit includes a phase detector for receiving a data signal and a clock pulse and for outputting a pump-up signal and a pump-down signal, a pulse divider connected to the phase detector for receiving the pump-up signal and the pump-down signal and producing a first output at predetermined multiples of the pump-up signal and a second output at predetermined multiples of the pump-down signal. A pulsed filter or integrator is connected to the pulse divider for receiving the first output and the second output and providing a frequency control signal for a voltage controlled oscillator. A three state amplifier is connected to the phase detector for receiving the pump-up signal and the pump-down signal and providing a phase control signal for a voltage controlled oscillator. The voltage controlled oscillator is connected to the pulsed filter and the amplifier for receiving the frequency control signal and the phase control signal and producing a corresponding output.

Abstract: A programmable logic device having a plurality of programmable elements includes a fast verify method and test circuit for programming the programmable logic device. The test circuit includes a serial input port and an address storage element which receives address information from the serial input port. The test circuit also incudes a data storage element which receives program data from the serial input port. The test circuit additionally includes control logic coupled to the address storage element and the data storage element. The control logic controls when the program data is provided to a memory location and read from a memory location as verify data. The test circuit further includes verify logic coupled to the data storage element and the memory location. The verify logic generates an output signal in response to a comparison of the verify data and the program data. The verify logic uses the program data as a mask in generating the output signal.

Abstract: A memory system includes a memory and a controller coupled to the memory and a system bus. The controller is configured to receive a bus clock and control signals over the system bus and to provide memory control signals with a predetermined timing resolution to the memory. The controller includes a bus clock frequency multiplication circuit for generating an internal clock signal which is used to generate the memory control signals, and a programmable timing register for storing timing intervals of the memory control signals. The bus frequency multiplication circuit generates the internal clock signal by multiplying the frequency of the bus clock by a bus frequency multiplication factor which is selectively chosen to set the predetermined timing resolution for the memory control signals to a nearly constant value independent of the frequency of the bus clock. The bus frequency multiplication circuit may comprise a phase locked loop.

Abstract: A circuit for latching inputs and enabling outputs on a bidirectional pin using a PLL lock detect circuit is disclosed. A PLL lock detect circuit generates an active lock control signal when an output reference signal is phase locked relative to an input reference signal applied to a phase locked loop (PLL) circuit. A latch and enable circuit is responsive to this lock control signal to latch the input signal (off of the pin), and, thereafter, enable output of an output signal onto the bidirectional pin. The latch and enable circuit includes a data latch to store the input signal when the lock control signal goes to an active state. The latch and enable circuit also includes a delay circuit to delay the lock control signal to produce a delayed lock control signal, and a tristateable output driver that is tristated when the delayed lock control signal is inactive, but, operates to pass (i.e., enable) the output signal to the bidirectional pin when the delayed lock control signal is active.

Abstract: A method is described for accessing data in a memory that has a first memory plane and a second memory plane. The method includes the step of sending a first plurality of data from the first memory plane to a data port. A second plurality of data from the second memory plane is pre-fetched only while the first plurality of data is sent from the first memory plane. The pre-fetching is performed a first plurality of clock cycles before the second plurality of data is sent to the data port.

Abstract: A method for generating an optimal serial test pattern for sequence detection. The serial test pattern comprises a first plurality of bits and is generated by a pattern generator. The method comprises generating a second plurality of bits having a first value and a least significant bit. The second plurality of bits includes less bits than the first plurality of bits. The first value of the second plurality of bits is then compared with at least one number. A next bit is then generated in the serial pattern. If the first value of the second plurality of bits is equal to the at least one number, the next bit has a same state as the least significant bit in the second plurality of bits. If the second plurality of bits is not equal to the at least one number, the next bit has a complement state of the least significant bit in the second plurality of bits. For one embodiment, the second plurality of bits comprises n bits, and the at least one number comprises one through 2.sup.n-1 inclusive.