摘要:
A non-volatile memory cell is provided that includes a low voltage CMOS storage transistor having a source region and a drain region that are commonly connected to ground. The low voltage storage transistor is programmed by applying a high programming voltage to its gate, thereby rupturing the gate oxide of the storage transistor. The high programming voltage is applied to the low voltage storage transistor through a high voltage p-channel transistor. The high voltage p-channel transistor has a thicker gate oxide than the storage transistor, thereby enabling the p-channel transistor to withstand higher voltages. The high voltage p-channel transistor also has a higher breakdown voltage than a high voltage n-channel transistor of the same size. Both the low voltage storage transistor and the high voltage p-channel transistor are fabricated in accordance with a standard sub 0.35 micron process. The state of the low voltage storage transistor can be read through the p-channel transistor, or through a dedicated high voltage n-channel transistor. In one embodiment, the programming voltage is generated by a charge pump circuit fabricated in accordance with a standard sub 0.35 micron process. In another embodiment, the decoder circuits that access the non-volatile memory cell use high voltage p-channel transistors to transmit the high programming voltage. Another embodiment of the present invention includes a system-on-a-chip structure that implements the non-volatile memory of the present invention.
摘要:
A method of testing of an embedded core of an integrated circuit (“IC”) is described. An IC has a hardwired embedded core and memory coupled to each other in the IC. The method includes writing a test vector to the memory while the embedded core is operative. The test vector is input from the memory to the embedded core to mimic scan chain input to the embedded core. A test result is obtained from the embedded core responsive in part to the test vector input.
摘要:
A method and apparatus are disclosed that simplify and reduce the time required for detecting faults in a programmable device such as a programmable logic device (PLD) by utilizing fault coverage information corresponding to a plurality of test patterns for the PLD to reduce the set of potential faults. For one embodiment, each test pattern is designated as either passing or failing, the faults that are detectable by at least two failing test patterns and the faults that are not detectable by any passing test patterns are eliminated, and the remaining faults are diagnosed. For another embodiment, the faults detectable by each failing test pattern are diagnosed to generate corresponding fault sets, and the faults not common to the fault sets and not detectable by one or more of the failing test patterns are eliminated.
摘要:
A new method to test short faults in a programmable logic device is described. The line segments under test are connected together to form a conducting chain. All the line segments neighboring to the conducting chain are tied to a known state. A test vector is applied to the programmable logic device. The state of the line under test is measured. If it is the same as the known state, the programmable logic device is likely to have faults.
摘要:
A Built-in Self Test (BIST) system is provided in a Field Programmable Gate Array (FPGA) that can adjust test signal patterns provided for testing after partial reconfiguration of the FPGA. The BIST system includes a decoder that monitors I/O signals and provides an output indicating when I/O signals change indicating partial reconfiguration has occurred. The decoder output is provided to a BIST test signal generator providing signals to an IP core of the FPGA as well as a BIST comparator for monitoring test results to change test signals depending on the partial configuration mode.
摘要:
Disclosed are methods for utilizing programmable logic devices that contain at least one localized defect. Such devices are tested to determine their suitability for implementing selected designs that may not require the resources impacted by the defect. If the FPGA is found to be unsuitable for one design, additional designs may be tested. The test methods in some embodiments employ test circuits derived from a user's design to verify PLD resources required for the design. The test circuits allow PLD vendors to verify the suitability of a PLD for a given user's design without requiring the PLD vendor to understand the user's design.
摘要:
A radiation hardened NMOS transistor structure suited for application to radiation hardened CMOS devices, and the method for manufacturing it is disclosed. The new transistor structure is characterized by "P" doped guard bands running along and immediately underlying the two bird's beak regions perpendicular to the gate. The transistor and the CMOS structure incorporating it exhibit speed and size comparable to those of conventional non-rad-hard CMOS structure, relatively simple manufacturing, and excellent total-dose radiation hardness.
摘要:
Methods and systems generate a manufacturing test of a programmable integrated circuit and optionally test the programmable integrated circuit with the manufacturing test. A netlist is generated that represents a specific user design implemented in programmable resources of the programmable integrated circuit. The netlist represents user registers that are implemented in a portion of the logic registers of the programmable logic resources. A virtual scan chain is added to the netlist. Scan-test vectors are generated from the netlist using automatic test pattern generation (ATPG). The scan-test vectors serially scan the portion of the logic registers via the virtual scan chain. The scan-test vectors are converted into access-test vectors that access the portion of the logic registers via a configuration port of the programmable integrated circuit. The programmable integrated circuit is optionally tested for a manufacturing defect with the access-test vectors.
摘要:
A CMOS integrated circuit structure is disclosed having a patterned nitride passivation layer, wherein the nitride is patterned such that it does not overlie the thin gate oxide portions of one or more of the MOS devices. When protection against the effects of external radiation is desired, the thin gate oxide areas of the PMOS devices are left uncovered by the patterned nitride passivation layer. When protection is desired against the effects of internally generated "hot electrons", the thin gate oxide areas of the NMOS devices are left uncovered by the patterned nitride passivation layer.
摘要:
A technique for improving the radiation hardness and hot-electron resistance of a CMOS integrated circuit is described whereby undesirable hydrogen ions may be vented through any holes, such as contact holes, in an overlying passivation layer by applying an elevated temperature and/or electrical bias to the integrated circuit die. The elevated temperature and electrical bias serve to accelerate the process by which hydrogen vents from the die. The elimination of unwanted hydrogen significantly reduces threshold shifts in the CMOS integrated circuit, providing greater radiation hardness and hot-electron resistance.