Abstract: The present invention provides a tunable circuit for quickly optimizing an electrical field generated by the F-N tunneling operation. To optimize this electrical field, the charging of the positive charge pump is begun after the charging of the negative charge pump. The tunable circuit of the present invention provides a means to detect the optimal negative voltage at which pumping of the positive voltage should begin. The tunable circuit includes a resistor chain coupled between a first reference voltage and a negative voltage from a negative charge pump. When charging of the negative charge pump begins, a comparator compares the voltage at a node within the resistor chain to a second reference voltage. In accordance with the present invention, the node voltage within the resistor chain is equal to the second reference voltage when the negative voltage is equal to the voltage to be detected.

Abstract: A PLD can be manufactured to include power supply lines from two sources so that a portion of the PLD can be backed up with a battery when power to the PLD is removed. A switch that supplies power to the backed up portion of the PLD receives power from both an external power supply and from the battery, and detects voltage level of the external power supply, switching to battery power when voltage from the external power supply is not sufficient.

Abstract: A field programmable gate array (FPGA) includes a first non-volatile memory cell and a second non-volatile memory cell. Each of the two non-volatile memory cells is capable of storing at least one bit of information. The second non-volatile memory cell provides redundant storage of the information stored in the first non-volatile memory cell. A read circuit is coupled to the first non-volatile memory cell and the second non-volatile memory cell. The read circuit simultaneously reads the information stored in the first and second non-volatile memory cells, The read circuit reads the information stored in the first non-volatile memory cell even if the second non-volatile memory cell is defective or is not programmed properly. The FPGA may include a third non-volatile memory cell coupled to the read circuit, which provides redundant storage of the information stored in the first non-volatile memory cell.

Abstract: A system and method for evolving configuration bitstreams for a programmable logic device are disclosed. A plurality of data structures having respective sets of data are established. From the sets of data, respective configuration bitstreams are generated, wherein the sets of data are mapped to positions in the bitstreams. The configuration bitstreams are then evaluated for relative suitability to meet predetermined criteria when deployed on a progammable logic device. From the relative suitability of the configuration bitstreams, next-generation data for the data structures are generated using a genetic algorithm applied to sets of data. In the various embodiments, the configuration bitstreams eliminate resource contentions, selectively eliminate asynchronous behavior, include built-in test circuits, and are relocatable. Multiple populations of configuration bitstreams can evolve in parallel over a network.

Abstract: A system and method for evolving configuration bitstreams for a programmable logic device are disclosed. A plurality of data structures having respective sets of data are established. From the sets of data, respective configuration bitstreams are generated, wherein the sets of data are mapped to positions in the bitstreams. The configuration bitstreams are then evaluated for relative suitability to meet predetermined criteria when deployed on a programmable logic device. From the relative suitability of the configuration bitstreams, next-generation data for the data structures are generated using a genetic algorithm applied to sets of data. In the various embodiments, the configuration bitstreams eliminate resource contentions, selectively eliminate asynchronous behavior, include built-in test circuits, and are relocatable. Multiple populations of configuration bitstreams can evolve in parallel over a network.

Abstract: A system and method for evolving configuration bitstreams for a programmable logic device are disclosed. A plurality of data structures having respective sets of data are established. From the sets of data, respective configuration bitstreams are generated, wherein the sets of data are mapped to positions in the bitstreams. The configuration bitstreams are then evaluated for relative suitability to meet predetermined criteria when deployed on a programmable logic device. From the relative suitability of the configuration bitstreams, next-generation data for the data structures are generated using a genetic algorithm applied to sets of data. In the various embodiments, the configuration bitstreams eliminate resource contentions, selectively eliminate asynchronous behavior, include built-in test circuits, and are relocatable. Multiple populations of configuration bitstreams can evolve in parallel over a network.

Abstract: A RAM block includes a circuit for causing the RAM to provide a reset value on the output or a previously captured output value from the RAM when a Reset signal is active. The Reset signal does not change the RAM contents but causes all outputs of the block RAM to be either a reset value or a capture value, as selected by the user. This is useful when the RAM block is configured as a state machine. Thus, in an FPGA or other programmable device, an application can start the state machine in a known state with all address bits equal to 0 and can reset the state machine to this startup state. When the reset signal is active, the state machine can feed back the reset value or capture value to the address inputs of the RAM block that receive state feedback data, regardless of the data actually in those locations.

Abstract: In an FPGA having four-input lookup tables (LUTs) with parallel two-input AND gates receiving two of the four LUT input signals, associated registers, and a carry chain receiving one input signal from the AND gate output, a loadable up-down counter is formed by connecting the register output to one of the terminals serving as both a LUT input terminal and an AND gate input terminal. A load control signal is connected to another input terminal common to the LUT and the AND gate. Thus the AND gate disables the carry chain during loading of the counter and applies the count value to the carry chain during counting.

Abstract: A RAM block includes a circuit for causing the RAM to provide all 0's on the output when a Reset signal is active. The Reset signal does not change the RAM contents but causes all outputs of the block RAM to be 0. This is useful when the RAM block is configured as a state machine. Thus, in an FPGA or other programmable device, an application can start the state machine in a known state with all address bits equal to 0 and can reset the state machine to this startup state. When the reset signal is active, the state machine feeds back the state of 0 to the address inputs of the RAM block that receive state feedback data, regardless of the data actually in those locations.

Abstract: A heterogeneous integrated circuit device comprising a field programmable gate array (FPGA) programmably connected to a mask-defined application specific logic area (ASLA) on an integrated circuit thus providing a flexible low cost alternative to a homogeneous device of one type or the other. By integrating both on a single monolithic IC, the user benefits from both low cost and flexibility. Routing of signals between gate arrays and between the gate arrays and input/output (I/O) circuits is also implemented as a combination of mask-defined and programmably-configured interconnections.