Abstract: In one aspect, apparatus and method are provided for communicating data in the form of transmission symbols conveyed in a carrier signal, wherein each transmission symbol is from a symbol set comprising a plurality of symbols which are collectively capable of representing any combination of values for at least three bits of data, wherein each symbol of the symbol set is defined with at most one transition of signal level in the carrier signal. In another aspect, apparatus and method are provided for communicating any combination of values for at least three data bits in the form of a respective transmission symbol conveyed in a carrier signal, wherein the transmission symbol is uniquely defined by a respective combination of a signal level transition, a lack of signal level transition, a signal region, and a cross-over between signal regions in the carrier signal.

Abstract: A synchronous bus system includes a clock line having a forward direction clock segment and a reverse direction clock segment connected to each of a plurality of devices. The forward direction clock segment carries a forward direction clock signal, and the reverse direction clock segment carries a reverse direction clock signal. Synchronization clock circuitry, provided in each device, receives the forward direction clock signal and the reverse direction clock signal. Using the received clock signals, the synchronization clock circuitry derives a universal synchronization clock signal which is synchronous throughout all devices. Skew correction circuitry, provided in at least a portion of the devices, corrects for skew between the universal synchronization clock signal and one or more data signals for transferring data between devices.

Abstract: An apparatus for providing multi-symbol signaling includes a multi-symbol encoder circuit. The multi-symbol encoder circuit is operable to encode data into a plurality of symbols, each symbol uniquely defined by a signal transition and a signal region in a carrier signal. A driver circuit, coupled to the multi-symbol encoder circuit, is operable to drive the carrier signal.

Abstract: A synchronous bus system includes a clock line having a forward direction clock segment and a reverse direction clock segment connected to each of a plurality of devices. The forward direction clock segment carries a forward direction clock signal, and the reverse direction clock segment carries a reverse direction clock signal. Synchronization clock circuitry, provided in each device, receives the forward direction clock signal and the reverse direction clock signal. Using the received clock signals, the synchronization clock circuitry derives a universal synchronization clock signal which is synchronous throughout all devices. Skew correction circuitry, provided in at least a portion of the devices, corrects for skew between the universal synchronization clock signal and one or more data signals for transferring data between devices.

Abstract: An I/O interface circuit includes an output buffer circuit and an input buffer circuit. The output buffer circuit can receive a first stream of data elements for output from the semiconductor chip, add a separate reference element for each data element in the first stream, and generate a first data transmission signal representing the data elements of the first stream and the respective reference elements. The input buffer circuit can receive a second data transmission signal representing data elements of a second stream and respective reference elements for the data elements of the second stream, sample the second data transmission signal to obtain voltage values for each data element of the second stream and the respective reference element, and interpret the voltage value for each data element of the second stream against the voltage value for the respective reference element in order to recover the data elements of the second stream.

Abstract: An advanced input/output interface is provided for an integrated circuit memory having a memory storage array accessible by signals formatted in a two-level protocol. The advanced input/output interface includes a bit compression circuit for receiving a first plurality of signals formatted in the two-level protocol and generated within the integrated circuit memory. The bit compression circuit converts the first plurality of two-level protocol signals into a first signal formatted in a multi-level protocol. A bit decompression circuit receives a second signal formatted in the multi-level protocol. The bit decompression circuit converts the second multi-level protocol signal into a second plurality of signals formatted in the two-level protocol. In one embodiment, the advanced input/output interface allows for high speed/bandwidth memory accesses while reducing the pin count and operating frequency required for operation.

Abstract: A frame buffer including a memory array, circuitry for accessing the array, a plurality of latches each capable of storing a plurality of pixel values equivalent to a large portion of a row of pixels in the array which may be read simultaneously from the array, and circuitry for writing simultaneously to the memory cells of a row of the array the data stored in the latches whereby a row of pixels may be read and written back to the array bus in a minimum time period.

Abstract: A frame buffer designed to allow frame buffer operations which do not involve new row addresses to be accomplished without the need for a RAS cycle. The elimination of RAS cycles for address loading and similar functions substantially accelerates the operation of the frame buffer both as to functions which do not involve memory array addresses and those which do involve memory array addresses.

Abstract: An intermediate Dc voltage generator providing low standby current. The present invention is a CMOS-based integrated circuit that generates a reference voltage level. The present invention accomplishes this task while also minimizing power consumption allowing application for portable computers or other battery-operated devices. The present invention replaces the second stage transistors of the prior art with transistors that have channel lengths greater than the channel lengths of the first stage transistors. This increases the turn on voltage of the second stage transistors. In addition, the channel width of the second stage transistors is less than the channel width of the first stage transistors further increasing turn on voltage. In this way, the second stage transistors are off, reducing the switching current and standby current contributed by the driver transistors at second stage, and providing intermediate level voltage references.

Abstract: A power-on reset circuit. The reset circuit provides an automatic reset pulse immediately after power-up. The supply voltage is provided to the reset circuit. An RC filter with a variable time constant provides a "hump" waveform which is coupled to a waveform shaper. The waveform shaper converts the hump voltage output from the RC filter into a reset signal. Latching mechanisms are included to prevent refiring of the reset signal.

Abstract: The present invention implements a static inverter-type TTL/CMOS level translator. The present invention utilizes a pair of transistors to suppress hot electron effects. The transistor pair limits maximum VDS to VCC-VTN at the first and second gain stages. A pair of resistors serve as a virtual VCC modulator to minimize voltage variations, stabilizing the VIL/VIH trip point. The resistors also minimize standby current so that the translator of the present invention can be used in a low standby current environment. The translator of the present invention provides faster speed, wider process margins, better reliability and lower standby current than prior art translators.