Abstract: A debug circuit for a multi-mode circuit driven by a clock signal, with an input for a clock signal, and a debug signal generator arranged to generate for each of a subset of the modes of the multi-mode circuit a corresponding debug signal based on a clock signal provided at the input. The frequency of debug signals is dependent on the frequency of a clock signal provided at the input, and each debug signal selects its respective mode for a length of time longer than that of each other mode of the multi-mode circuit, or each debug signal selects its respective mode for a length of time shorter than that of each other mode of the multi-mode circuit.

Abstract: The present invention relates to controlling the timing of a clock signal in high speed circuits, such as an analogue-digital converter (ADC). In some high speed data transfer techniques, the incoming data is latched using a clock signal. Often, the delay between the incoming data being clocked into the circuit and being ready to use (referred to as the “clock-to-Q period”) is large enough to cause problems. In particular, the clock-to-Q period may be sufficient to result in the original clock signal being inappropriate to clock the latched signal.

Abstract: The present invention relates to controlling the timing of a clock signal in high speed circuits, such as an analogue-digital converter (ADC). In some high speed data transfer techniques, the incoming data is latched using a clock signal. Often, the delay between the incoming data being clocked into the circuit and being ready to use (referred to as the “clock-to-Q period”) is large enough to cause problems. In particular, the clock-to-Q period may be sufficient to result in the original clock signal being inappropriate to clock the latched signal.

Abstract: A debug circuit for a multi-mode circuit driven by a clock signal, with an input for a clock signal, and a debug signal generator arranged to generate for each of a subset of the modes of the multi-mode circuit a corresponding debug signal based on a clock signal provided at the input. The frequency of debug signals is dependent on the frequency of a clock signal provided at the input, and each debug signal selects its respective mode for a length of time longer than that of each other mode of the multi-mode circuit, or each debug signal selects its respective mode for a length of time shorter than that of each other mode of the multi-mode circuit.

Abstract: The present invention relates to the reduction in errors in the phase of quadrature clock signals and provides a correction circuit for signals which are required to have as close to that precise phase relationship as possible. The arrangement is based upon a circuit which aims to bring signals which should be 180 degrees apart closer to a 50% duty cycle.

Abstract: A digital system aligns a set of serial data receiver demultiplex circuits, thereby aligning the bits in the data words, while maintaining separate and optimally aligned data recovery clocks for each channel. The digital system generates a reference clock signal and one or more slave clock signals. Phase circuitry receives the slave clock signal and outputs a plurality of clock phase signals. A phase selection circuit receives the plurality of clock phase signals and selects an adjusted clock signal in response to a phase selection signal. A clock correlation circuit determines a phase difference between the reference clock signal and the adjusted clock signal and provides the phase selection signal to minimize the phase difference. The clock correlation circuit provides the phase selection signal from a counter.

Abstract: A digital system is provided with a means for achieving alignment between a set of serial data receiver demultiplex circuits, thereby achieving alignment of the bits in the data words, while maintaining the use of separate and therefore optimally aligned data recovery clocks for each channel signal. The digital system is provided with circuitry for generating a reference clock signal and clock circuitry for generating one or more slave clock signals. Phase circuitry is connected to receive the slave clock signal and has outputs for providing a plurality of clock phase signals. A phase selection circuit is connected to receive the plurality of clock phase signals. The phase selection circuit has an output for providing an adjusted clock signal selected from the plurality of clock phase signals in response to a phase selection signal.

Abstract: An asynchronous time division multiplex switching arrangement comprises a serial to parallel converter arranged to receive input packets of data which include routing information, in serial form and convert the packets of data to parallel form. A random access memory is provided in which each packet of data is entered at an addressed location into the memory, and the address is entered in a respective first-in first-out output queue at the tail. The address at the head of the queue is accessed and the packet of data is read from the random access memory into a parallel to serial converter and the packet of data is serially delivered to the associated output.

Abstract: A digital data interface for high speed asynchronous data transfer is described. The design is nominally intended for integration onto the component chips in communications systems. The system is described with respect to its realization in CMOS IC technology. The techniques involved, however, may easily be applied to other technologies. The interface employs Manchester Bi-Phase Mark encoding of the clock and data to allow extraction of the clock and data signals at the receiver. Furthermore, use of this Manchester code allows code violations to be easily employed as frame markers for synchronization means. The essence of the clock extraction and data detection circuit is the use of calibrated delay line elements to suppress data transitions within the coded input signal, thus allowing the clock transitions to be detected from which the clock is then generated.

Abstract: A method (FIG. 3) for producing MOS transistors of the type having shallow, lightly doped, source/drain structure. In this method sidewall fillets (7) of n-type doped dielectric material are defined adjacent to the sides of the oxide (1) and metal electrode (3) features. These fillets (7) are then employed to provide self aligned masking during implantation of heavy dopant of either n- or p- type (9; 13). In a subsequent rapid anneal step, the implant dopant is activated and n-type dopant diffused into the substrate (5) from the fillets (7) to provide lightly doped source/drain structures (11; 15).Examples of this method are described for producing phosphorus-arsenic n.sup.- /n.sup.+ are phosphorus-boron p.sup.- /p.sup.+ source/drain structures.