摘要:
A field programmable gate array (FPGA) and a decryption circuit are implemented within a common integrated circuit (IC) or within separate ICs enclosed within a common IC package. The decryption circuit decrypts an input FPGA program encrypted in accordance with a particular encryption key and then writes the decrypted FPGA program into the FPGA. Thus an FPGA program encrypted in accordance with a particular encryption key can be used to program only those FPGAs coupled with a decryption circuit capable of decoding the encrypted FPGA program in accordance with that particular encryption key. Since the decryption circuit and the FPGA are implemented in the same IC, or within the same IC package, the decrypted FPGA program the decryption circuit produces cannot be readily intercepted and copied.
摘要:
A flexible built-in self-test (BIST) circuit is incorporated into an integrated circuit (IC) for testing one or random access memories or other memories embedded in an integrated circuit regardless of the number, size or test requirements of the memories. Input data from a controller that may be conveniently partitioned among components internal and external to the IC, supplies data to the BIST circuit indicating the size of the embedded memories to be tested and selecting from among several modes of BIST operation.
摘要:
A built-in replacement analysis (BIRA) circuit allocates spare rows and columns of cells for replacing rows and columns of an array of memory cells in response to an input sequence of cell addresses, each identifying a row address and a column address of each defective cell of the cell array. The BIRA subsystem, including a row register corresponding each spare row and a column register corresponding to each spare column, responds to incoming cell addresses by writing their included row address into the row registers, by writing their column addresses into the column registers, and by writing link bits into the column registers. Each link bit links a row and a column register by storing row and column addresses of a defective cell. The BIRA subsystem also writes a “multiple cell” bit into each row register to indicate when the row address it stores includes more than one defective cell. The row and column addresses stored in these registers indicate the array rows and columns for which spare rows and columns are to be allocated. Each row and column register also includes a “permanent” bit the BIRA subsystem sets to indicate when the spare row or column allocation indicated by its stored row or column address is permanent. The BIRA subsystem efficiently allocates spare row and columns by manipulating the data stored in the row and column registers in response to a sequence of defective cell address.
摘要:
A carrier module that is able to adapt non-standard instrument cards to the architecture of a test system is disclosed. Instrument cards based on non-standard architectures may be combined on a single carrier module. The carrier module is then plugged into the test head of the test system. The carrier module provides circuitry, contained on a plug-in sub-module called an Application Interface Adapter (AIA), to interface between the instrument cards and the test head interface connector. Additionally, the AIA may also provide access from the instrument cards to ATE system calibration circuitry. The carrier module uses the standard data bus of the test system for housekeeping and control functions. A second bus provides the bus for the non-standard instrument cards. Software drivers provided with the instrument cards are encapsulated with an appropriate wrapper so that the cards run seamlessly in the software environment of the test system.
摘要:
The animal control tether comprises an elongated body, first and second handles, and a clasping device. The elongated body has a first end section and a second, opposite end section. The first handle is located at the first end section of the elongated body for providing relatively distant control over an animal. The clasping device is affixed to the second end section of the elongated body. The second handle is located at the second end section. The second handle is constructed so as to remain slack, regardless of any tension exerted on the elongated body by an animal during use, until the second handle is grasped by an animal handler desiring close control over the animal's movements.
摘要:
A carrier module that is able to adapt non-standard instrument cards to the architecture of a test system is disclosed. Instrument cards based on non-standard architectures may be combined on a single carrier module. The carrier module is then plugged into the test head of the test system. The carrier module provides circuitry, contained on a plug-in sub-module called an Application Interface Adapter (AIA), to interface between the instrument cards and the test head interface connector. Additionally, the AIA may also provide access from the instrument cards to ATE system calibration circuitry. The carrier module uses the standard data bus of the test system for housekeeping and control functions. A second bus provides the bus for the non-standard instrument cards. Software drivers provided with the instrument cards are encapsulated with an appropriate wrapper so that the cards run seamlessly in the software environment of the test system.
摘要:
A method and circuit are provided for generating a minimum-sized address filter to detect when the address space of an embedded memory having a smaller address space than another larger embedded memory is being exceeded. The method includes decomposing a maximum address into alternating sequences of consecutive binary ones (1's) and zeros (0's), discarding a final sequence if it contains binary 1's, and generating a filter circuit from a filter function formed from the alternating sequences of consecutive binary 1's and 0's. A built-in self test (BIST) circuit incorporating the address filter provides the ability to test a plurality of embedded memories at full speed in parallel. A computer system including a computer program for generating the filter circuit may also be provided.
摘要:
A carrier module that is able to adapt non-standard instrument cards to the architecture of a test system is disclosed. Instrument cards based on non-standard architectures may be combined on a single carrier module. The carrier module is then plugged into the test head of the test system. The carrier module provides circuitry, contained on a plug-in sub-module called an Application Interface Adapter (AIA), to interface between the instrument cards and the test head interface connector. Additionally, the AIA may also provide access from the instrument cards to ATE system calibration circuitry. The carrier module uses the standard data bus of the test system for housekeeping and control functions. A second bus provides the bus for the non-standard instrument cards. Software drivers provided with the instrument cards are encapsulated with an appropriate wrapper so that the cards run seamlessly in the software environment of the test system.
摘要:
A BIST function is provided in which both the routing area devoted to the test signals and the area devoted to the circuits required to implement the BIST routines are minimized, while also including the ability to test a plurality of embedded memories at full speed in parallel. Testing the memories at full speed both reduces test time and improves the quality of the testing.
摘要:
A BIST function is provided in which both the row address and the column address of a memory to be tested may be selected independently. The present invention provides flexibility in selecting addresses to be tested, improves transition time between rows, and allows determination of which memory address passes or fails the test.