Abstract:
A transceiver system with reduced latency uncertainty is described. In one implementation, the transceiver system has a word aligner latency uncertainty of zero. In another implementation, the transceiver system has a receiver-to-transmitter transfer latency uncertainty of zero. In yet another implementation, the transceiver system has a word aligner latency uncertainty of zero and a receiver-to-transmitter transfer latency uncertainty of zero. In one specific implementation, the receiver-to-transmitter transfer latency uncertainty is eliminated by using the transmitter parallel clock as a feedback signal in the transmitter phase locked loop (PLL). In one implementation, this is achieved by optionally making the transmitter divider, which generates the transmitter parallel clock, part of the feedback path of the transmitter PLL. In one implementation, the word aligner latency uncertainty is eliminated by using a bit slipper to slip bits in such a way so that the total delay due to the word alignment and bit slipping is constant for all phases of the recovered clock. This allows for having a fixed and known latency between the receipt and transmission of bits for all phases of parallelization by the deserializer. In one specific implementation, the total delay due to the bit shifting by the word aligner and the bit slipping by the bit slipper is zero since the bit slipper slips bits so as to compensate for the bit shifting that was performed by the word aligner.
Abstract:
A multiplexer includes a first input device that receives a first input signal and a first select signal. When the first select signal has a first state, the first input device generates a first voltage at a first node in response to the first input signal. When the first select signal has a second state, the first input device generates a first reference voltage at the first node. A second input device receives a second input signal and a second select signal related to the first select signal. When the second select signal has a first state, the second input device generates a second voltage at a second node in response to the second input signal. When the second select signal has a second state, the second input device generates a second reference voltage at the second node. A first output buffer has an input terminal coupled to the first node and an output terminal coupled to an output node. The first output buffer tracks the first voltage at the output terminal, and presents a high impedance at the output terminal when the first reference voltage is present at the first node. A second output buffer has an input terminal coupled to the second node and an output terminal coupled to the output node. The second output buffer tracks the second voltage at the output terminal, and presents a high impedance at the output terminal when the second reference voltage is present at the second node.
Abstract:
An interface is disclosed that formats a first link (a source link--e.g., a T1 link) having N channels to fit into a second link (a source link--e.g., a PCM-30 or a doubled T1 link) having N+M channels. Each of the first and second links are implemented with primary rate carrier links, and have a standard payload portion and a standard overhead portion. A mechanism is disclosed for routing information between the first link and the second link, so that information being transported over the first link can also be transported over the second link. An adding mechanism is also disclosed for routing supplemental overhead information to at least one added overhead channel within the second link, wherein the added overhead channel occupies a standard payload portion of the second link. An overhead information bit is disclosed, which transmits information within a (k)th bit of an (l)th channel of each frame of the second link. An information bit signal is formed with at least five consecutive of the (k)th bits. Using the formed information bit signal, information is conveyed regarding the communications link. A path overhead byte is provided for transportation within the added overhead channel of the second link, and includes various overhead bits, including, e.g., the information bit noted above, for performing several maintenance and performance monitoring functions. Four of the bits within the path overhead byte are essentially equivalent to bits within an overhead byte provided for SONET networks.
Abstract:
An ultra low cost electric vehicle heating apparatus, components thereof, and related method are herein described. A driver circuit operates a switching device at an intermediate state between fully-turned-off and fully-turned-on, in a high power dissipation heating mode, to efficiently produce heat energy for heating a passenger compartment, or energy storage system, of an electric vehicle. The driver circuit operates the switching device to have a fully-turned-off state and a fully-turned-on state in a main function mode for a traction inverter or an energy storage system charger of the electric vehicle. The driver circuit is operable to cycle the heating mode and the main function mode for combining such heating and such main function operation of the traction inverter, or the charger, without compromising the operation of the traction motor, or charger, while simultaneously eliminating many of the expensive resistive heating components in use by practitioners of the art.
Abstract:
A data transmission method and apparatus provides for transmitting lower data rate information in a higher data transmission rate environment. Information entities to be transmitted are broken into smaller entitles called nyblets. Higher data transmission rates are accomodated by accelerating a clock and clocking nyblets from memory at rate that allows the nyblets to be serially assembled into expected bit length words. Lower data rate information, which in conventional systems was transmitted redundantly to achieve compatibility with higher data rate systems, is now transmitted without duplication as a plurality of nyblets in series until the expected bit length is achieved. The result is that more information can be transmitted over a communication medium, since duplicate or redundant transmission of lower data rate information is avoided.
Abstract:
A lamp is provided. The lamp includes at least one light emitting diode (LED) and an electronic circuit configured to provide power to the at least one LED. The lamp includes at least one flat circuit board having mounted thereto the at least one LED and the electronic circuit. The at least one flat circuit board acts as a heatsink to dissipate heat from the at least one LED and acts as a plurality of circuit paths for the electronic circuit and the at least one LED.
Abstract:
One or two Serializer/Deserializer (SerDes) modules are used to measure the time between two pulses with high resolution. A PLL inside a SerDes block is locked to a reference clock and an input signal is passed through a storage element to create a serial data stream that is converted into a parallel data stream by a demultiplexer inside the SerDes. The parallel data is stored in a bit logic unit that compares the parallel data to a second parallel data obtained in similar fashion in another SerDes from a second input signal. The time between the two pulses is then calculated as the number of cycles in the serial data stream that corresponds to the number of bits between the positions of the two events.
Abstract:
A light-emitting device includes a GaAs substrate, a light-emitting structure disposed above the substrate and capable of emitting light having a wavelength of about 1.3 microns to about 1.55 microns, and a buffer layer disposed between the substrate and the light-emitting structure. The composition of the buffer layer varies through the buffer layer such that a lattice constant of the buffer layer grades from a lattice constant approximately equal to a lattice constant of the substrate to a lattice constant approximately equal to a lattice constant of the light-emitting structure. The light-emitting device exhibits improved mechanical, electrical, thermal, and optical properties compared to similar light-emitting devices grown on InP substrates.
Abstract:
An improved phase-locked loop circuit includes a variable-frequency oscillator that generates a first oscillator signal, a reference signal source that generates a second oscillator signal, a control block that generates a select signal, and a frequency divider that receives as an input signal one of the first and second oscillator signals. The frequency divider also receives the select signal from the control block. The frequency divider generates a plurality of frequency-divided signals in response to the input signal, and passes through a selected one of the plurality of frequency-divided signals as an output signal in response to the select signal. The frequency divider also synchronizes its output signal to its input signal. The phase-locked loop also includes a frequency comparator that receives the output signal of the frequency divider and a signal derived from one of the first and second oscillator signals. The frequency comparator compares the output signal of the frequency divider to the signal derived from one of the first and second oscillator signals, and provides a feedback signal to the variable-frequency oscillator reflecting this comparison. In this phase-locked loop circuit, the number of signal regenerators introduced by the programmable frequency divider is effectively limited to one, thereby reducing the jitter introduced by the frequency divider.
Abstract:
A lamp is provided. The lamp includes at least one light emitting diode (LED) and an electronic circuit configured to provide power to the at least one LED. The lamp includes at least one flat circuit board having mounted thereto the at least one LED and the electronic circuit. The at least one flat circuit board acts as a heatsink to dissipate heat from the at least one LED and acts as a plurality of circuit paths for the electronic circuit and the at least one LED.