Abstract:
A circuit for providing a control signal for a load includes a first switch having a first and a second state, a second switch having a first and a second state coupled to said first switch, a load connected to said first and second switches, protection circuitry for protecting said load from excessive voltage and circuitry for switching said first switch. The circuit is arranged so that when the first switch is in the first state current flows from the load to the first switch and the switching circuitry is arranged to switch the first switch to the second state when the voltage across the load reaches a predetermined value.
Abstract:
An method of arranging address decoders in an improved manner in an integrated circuit memory is discussed. In the integrated circuit memory the address lines extending from the address circuitry of the integrated circuit memory are connected to address decoders, each word line of the memory being connected to an address decoder. The address decoders are connected to the address lines in a certain combination such that only one f the address lines is connected to adjacent address decoders. When connected in this manner the average propagation delay of each address line is substantially uniform. By reducing the maximum propagation delay in comparison with previously known arrangements of address decoders the speed at which the memory can be operated is increased.
Abstract:
A method is described for verifying the output from an analogue simulation model of a hardware circuit. The method comprises the steps of stimulating the analogue model by applying a preselected voltage to an input pin of the analogue model, driving one or more selected output pins of the analogue model with a test voltage having a selected drive strength different from an expected output drive strength, measuring the output voltage of each output pin, comparing the measured output voltage and the expected output voltage and responsive to said comparison, providing a verifying output if the measured and expected voltages are not in contradiction.
Abstract:
An executable program is prepared from a plurality of object code modules, each module including relocation instructions having an instruction format which includes a classification field for holding a relocation class indicator and a set of relocation fields for holding relocation data. The meaning of the relocation data depends on the class indicator. The instruction format is common to first and second classes of relocations. The executable program is prepared by reading the relocation instructions and determining from the relocation class indicator the class of the relocation instruction and executing the relocation operations on section data in dependence on the class of relocation instruction indicated by the relocation class indicator. A linker is provided for preparing the executable program from object code modules containing the relocation instructions. A computer program may be provided to control the linker.
Abstract:
A level shifter uses a current mirror as a current switch connected to the drains of two oppositely-driven FETs. A switch selectively connects the current mirror to its power supply so that no quiescent DC current flows.
Abstract:
An apparatus and method for determining the minimum clock delay first of all determines the response time of the overall circuit by varying the application instant of an external clock until the circuit output is just valid. Then an external senseamp clock is substituted for the internal senseamp clock and the instant of application of the external clock is again varied until the circuit output is just valid.
Abstract:
A fixed frequency dual downconversion receiver, comprises: an analog first downconversion (10) and IF filter stage (20); means for one-bit coding (24) of the downconverted signal; and means for second downconversion by digital subsampling (26,28). The receiver is particularly suitable for use in GPS applications.
Abstract:
A communication interface for interconnecting a computer with at least one other device has a link output circuit and a link input circuit. A link output on one device is connected to a link input on another device by a data line 25 and a parallel strobe line 26. Data is transmitted on the data line 25 in serial bit strings forming a succession of tokens of predetermined lengths. Signal transitions are provided on the parallel strobe line 26 where no signal transition occurs on the data line 25. Each token includes a bit indicating the length of the token and a parity bit providing a check on bits in a preceding token.