摘要:
A method provides a bidirectional communication protocol for data communication between a first device and a second device. The method includes: during a first time interval, transmitting data from the first device to the second device; and during a second time interval, (a) after the occurrence of a first event, (i) suspending data transmission from the first device to the second device; and (ii) transmitting control data from the second device to the first device; and (b) after the occurrence of a second event, transmitting control data from the first device to the second device.
摘要:
In a transceiver, a transmitter circuit is provided substantially the same common-mode voltage regardless of whether the transceiver is in a transmitting or receiving mode. In one embodiment, the transmitter circuit includes a driver circuit which, in the transmission mode of the transceiver, drives an output differential signal, and which, in the receiving mode of the transceiver, provides a termination circuit for an input differential signal. A variable resistor is provided to connect between a supply voltage and the driver circuit, the resistance of the variable resistor is selected such that the common-mode voltage of the output differential signal of the transmission mode substantially equals the common-mode voltage in the input differential signal of the receiving mode.
摘要:
A spread spectrum clock signal generator and an accompanying method provide a spread spectrum clock signal of a reduced electromagnetic interference. The spread spectrum clock signal generator includes (a) a state machine, which maintains a current state of the spread spectrum clock signal generator, receives as input value a next state of the spread spectrum clock signal generator and generates a clock phase selection signal based on the current and next states; (b) a random number generator for generating the next state; and (c) a waveform generation circuit for generating a spread spectrum clock signal based on the clock phase selection signal.
摘要:
The performance of the main regulatory transistor of an on-chip voltage regulator circuit is enhanced when the main transistor is appropriately biased during start up. In an example embodiment, a voltage regulator circuit includes a thin gate oxide transistor as the main regulatory transistor and an operational amplifier that is referenced to a midlevel operating voltage. During start-up, the potential voltage difference is large enough to necessitate the disconnection of the main transistor from the operational amplifier. A voltage divider ladder circuit is used to maintain the gate voltage of the main transistor at the midlevel voltage while a smaller thick gate oxide transistor is used to maintain loop stability and to withstand voltage transients.
摘要:
In a transceiver, a transmitter circuit is provided substantially the same common-mode voltage regardless of whether the transceiver is in a transmitting or receiving mode. In one embodiment, the transmitter circuit includes a driver circuit which, in the transmission mode of the transceiver, drives an output differential signal, and which, in the receiving mode of the transceiver, provides a termination circuit for an input differential signal. A variable resistor is provided to connect between a supply voltage and the driver circuit, the resistance of the variable resistor is selected such that the common-mode voltage of the output differential signal of the transmission mode substantially equals the common-mode voltage in the input differential signal of the receiving mode.
摘要:
A system comprising a first serializer/deserializer coupled to a first electronic device and a second serializer/deserializer couple to a second electronic device is provided. The first serializer/deserializer comprises a forward channel driver and the second serializer/deserializer comprises a reverse channel driver. A communication medium is coupled between the first and second serializer/deserializers, and the first and second serializer/deserializers are AC coupled to the communication medium to provide a high frequency forward channel and are DC coupled to the communication medium to provide a low frequency reverse channel.
摘要:
Multiple data streams are distributed using conventional data cables and multiplexing circuits by taking advantage of a technique that allows reliable high speed transmission of digital data. In one example, a number of parallel data streams (e.g., video data streams) are serialized to allow them to be economically and reliably transmitted over conventional data cables (e.g., category 5 or category 6 twisted pair cables, and automotive data transmission cables) over long distance. The parallel data streams are recovered by deserializing from the transmitted signal using a data recovery technique that recovers a clocking signal from the transmitted signal. In another example, multiple data streams from multiple asynchronous sources are multiplexed to provide an input data stream to a display device. The multiple data stream may be provided through, for example, conventional connection cables (e.g., DVI, LEONI, CATS or CAT6 cables).
摘要:
The performance of the main regulatory transistor of an on-chip voltage regulator circuit is enhanced when the main transistor is appropriately biased during start up. In an example embodiment, a voltage regulator circuit includes a thin gate oxide transistor as the main regulatory transistor and an operational amplifier that is referenced to a midlevel operating voltage. During start-up, the potential voltage difference is large enough to necessitate the disconnection of the main transistor from the operational amplifier. A voltage divider ladder circuit is used to maintain the gate voltage of the main transistor at the midlevel voltage while a smaller thick gate oxide transistor is used to maintain loop stability and to withstand voltage transients.
摘要:
A data retiming system for retiming incoming data and eliminating jitter is described. The data retiming system includes a local clock; a phase aligner for receiving the incoming data and producing a recovered clock from the incoming data, and then producing retimed incoming data by retiming the incoming data with the recovered clock; and a buffer memory for removing jitter from the retimed incoming data by storing the retimed incoming data to the buffer memory in accordance with the recovered clock and reading the stored data from the buffer memory in accordance with the local clock. The data retiming system provides reliable operation even at very high data rates. A freezeable voltage-controlled oscillator for producing a clock signal in accordance with a freeze signal and a frequency control signal is also disclosed. Using current steering techniques, the freezeable voltage-controlled oscillator is able to freeze its output very quickly.