摘要:
A method for generating charge sharing test vectors for a circuit is provided that includes providing an automatic test pattern generator operable to generate a first test vector (120) and a second test vector (122). The method further includes providing a test model (98) including a logic cell of a circuit and an auxiliary test circuit (100) where the auxiliary test circuit (100) includes a discharge AND gate (102) and a charge sharing AND gate (104). The method next provides for selecting an output of the discharge AND gate (104) as a target for a falling transition fault test vector generation by the automatic test pattern generator (124). The method next provides for generating a first test vector (120) for the test model (98) using the automatic test pattern generator (124) where the first test vector (120) provides an input pattern to discharge nodes of the logic cell. In addition, the discharge AND gate (102) evaluates to a logic level 1 for the first test vector (120). The method next provides for generating a second test vector (122) for the test model (98) using the automatic test pattern generator (124) where the second test vector (122) provides an input pattern to evoke the worst charge sharing behavior for the logic cell. In addition, the charge sharing AND gate (104) evaluates to a logic level 1 for the second test vector (122).
摘要:
A data storage circuit (30). The data storage circuit comprises a data input (12') for receiving a data voltage (D') and a node (17') for receiving an interim voltage in response to the data voltage. The data storage circuit also comprises an output enable circuit (32) for providing at least one conditional path coupled to the node and for coupling the interim voltage to the node. The output enable circuit comprises a transistor (32p) having a first threshold voltage and operable to provide a conductive path along the at least one conditional path. The data storage circuit also comprises a data output (19') for providing an output voltage in response to the interim voltage at the node and a data retention circuit coupled between the node and the data output. The data retention circuit (18' and 20') comprises at least one transistor having a second threshold voltage higher in magnitude than the first threshold voltage.
摘要:
In a preferred logic circuit embodiment (10), there is a precharge node (14) coupled to be precharged to a precharge voltage (V DD ) during a precharge phase and operable to be discharged during an evaluate phase. The circuit also includes a conditional series discharge path (22, 24, and 16) connected to the precharge node and operable to couple the precharge node to a voltage different than the precharge voltage. The conditional series discharge path includes a low threshold voltage transistor (22 or 24) having a first threshold voltage, and a high threshold voltage transistor (16) having a second threshold voltage higher in magnitude than the first threshold voltage, wherein a voltage connected to a gate of the high threshold voltage transistor is disabling during the precharge phase.
摘要:
A computer system uses microcode subroutines to execute complex macroinstruction. Each macroinstruction is used to index a table (18). Simple macroinstructions have a single microinstruction counterpart in the table (18), and such microinstruction is performed directly in order to execute that macroinstruction. The table entry corresponding to more complex macroinstructions is a jump microinstruction, with the target of the microcode jump being an appropriate subroutine in microcode memory (16).
摘要:
A cache memory addressable by both physical and virtual addresses includes a cache data memory (64) and a tag memory (66). The tag memory (66) is comprised of a virtual tag memory (68) and a physical tag memory (70). The physical and virtual tag memories are both addressable by the least significant bits (LSB) of the address signal to output tag portions of addresses associated with data stored in the cache data memory (64). A switch (78) selects between the outputs from the memories (68) and (70) under control of an arbitration unit (88). The arbitration unit (88) distinguishes between virtual or physical addresses input thereto. A comparator (100) compares the selected tag portion with the tag portion of the received address to determine if a match exists. If a match exists, the output of the cache data memory is selected with a switch (84).
摘要:
A dynamic logic circuit (30). The dynamic logic circuit comprises a precharge node (30 PN ) to be precharged to a precharge voltage (V DD ) during a precharge phase and a conditional discharge path (30 L , 30 DT ) connected to the precharge node. The conditional discharge path is operable, during an evaluate phase, to conditionally couple the precharge node to a voltage different than the precharge voltage. The dynamic logic circuit also comprises an output (OUT 3 ) for providing a signal in response to a state at the precharge node. Lastly, the dynamic logic circuit comprises voltage maintaining circuitry (30 KT1 , 30 KT2 ), coupled to the output, for coupling the precharge voltage to the precharge node during a portion of an instance of the evaluate phase when the conditional discharge path is not enabled during the instance of the evaluate phase.
摘要:
A processor (50) operable in response to an instruction set comprising a plurality of instructions. The processor comprises a functional unit (52) comprising an integer number S of sub-units (54 1 , 54 2 , 54 3 ), wherein S is greater than one. Each of the sub-units is operable to execute, during an execution cycle, at least one of the instructions in the instruction set in response to at least two data arguments (A, B). The processor further comprises circuitry (58 A1 , 58 A2 , 58 A3 , 58 B1 , 58 B2 ) for providing an updated value of the at least two data arguments to less than all S of the sub-units for a single execution cycle.
摘要:
A domino logic circuit (18) comprising a first phase domino logic circuit (20) operable in a precharge phase and an evaluate phase. The first phase domino logic circuit comprises a precharge (20 PN ) node operable to change states. The domino logic circuit also comprises a second phase domino logic circuit (22) operable in a precharge phase and an evaluate phase, wherein the precharge phase and the evaluate phase of the first phase domino logic circuit are out of phase with respect to the precharge phase and an evaluate phase of the second phase domino logic circuit. Further, the second phase domino logic circuit comprises a precharge node (22 PN ) operable to change states in response to the states of the first phase domino logic circuit. Each of the first and second phase domino logic circuits further comprises a coupling device (20 PT , 22 PT ) which when conducting couples the precharge node to a precharge voltage during a precharge phase and a discharge path (20L, 20DT; 22L, 22DT) connected to the precharge node which when conducting couples the precharge node to a voltage different than the precharge voltage during an evaluate phase, wherein the discharge path comprises logic circuitry. The first phase domino logic circuit is operable such that the precharge node of the first phase domino logic circuit is charged to a first state during the precharge phase of the first phase domino logic circuit, and the precharge node of the first phase domino logic circuit conditionally changes to a second state during the evaluate phase of the first phase domino logic circuit. The second phase domino logic circuit is operable such that the state of the precharge node of the second phase domino logic circuit may change in the evaluate phase of the second phase domino logic circuit and in response to the first phase domino logic circuit only when the state of the precharge node of the first phase domino logic circuit did not change in an immediately preceding evaluate phase of the first phase domino logic circuit.