Patent classifications
H03K5/15
Deskew circuit for differential signal
A deskew circuit for a differential signal is provided. A first common mode voltage generating circuit generates a first common mode voltage signal according to first and second differential input signals. A voltage buffer circuit is coupled to the first common mode voltage generating circuit and has an input impedance higher than a preset value, and buffers the first common mode voltage signal and the first and second differential input signals to generate a second common mode voltage signal, a third differential input signal, and a fourth differential input signal. A second common mode voltage generating circuit is coupled to the voltage buffer circuit and generates a third common mode voltage signal according to the third and fourth differential input signals. An output circuit generates a deskew output signal according to the third and fourth differential input signals and the second and third common mode voltage signals.
Deskew circuit for differential signal
A deskew circuit for a differential signal is provided. A first common mode voltage generating circuit generates a first common mode voltage signal according to first and second differential input signals. A voltage buffer circuit is coupled to the first common mode voltage generating circuit and has an input impedance higher than a preset value, and buffers the first common mode voltage signal and the first and second differential input signals to generate a second common mode voltage signal, a third differential input signal, and a fourth differential input signal. A second common mode voltage generating circuit is coupled to the voltage buffer circuit and generates a third common mode voltage signal according to the third and fourth differential input signals. An output circuit generates a deskew output signal according to the third and fourth differential input signals and the second and third common mode voltage signals.
CLOCK SPINE WITH TAP POINTS
Apparatuses and methods to relay a clock signal to clock loads are presented. An apparatus includes a clock spine to conduct a clocking signal. The clock spine includes multiple taps points distributed unevenly on the clock spine. The apparatus further includes multiple clock buffers. Each of the multiple clock buffers is connected to a corresponding one of the multiple tap points. The method includes conducting a clocking signal on a clock spine having multiple taps points. The multiple tap points are distributed unevenly on the clock spine. The method further includes buffering the clocking signal at each of the multiple tap points. Another method includes forming a clock spine to conduct a clocking signal. The clock spine includes multiple taps points. The multiple tap points are distributed unevenly on the clock spine. The method further includes forming multiple clock buffers.
Direct synchronization of synthesized clock
The Direct Synchronization of Synthesized Clock (DSSC) contributes a method, system and apparatus for reliable and inexpensive synthesis of inherently stable local clock synchronized to a referencing signal received from an external source. Such local clock can be synchronized to a referencing frame or a data signal received from wireless or wired communication link and can be utilized for synchronizing local data transmitter or data receiver. Such DSSC can be particularly useful in OFDM systems such as LTE/WiMAX/WiFI or Powerline/ADSL/VDSL, since it can secure lower power consumption, better noise immunity and much more reliable and faster receiver tuning than those enabled by conventional solutions.
Distributed multi-phase clock generator having coupled delay-locked loops
Multiple, distributed, clock generating delay-locked loop (DLL) elements are interconnected/coupled in such a way as to reduce the amount of phase error present in the clocks output by these DLL elements. A plurality of DLL elements are interconnected/coupled such that a root input clock is successively relayed down a series of DLL elements. The output clocks from each of these DLL elements are interconnected/coupled to phase-corresponding output clocks from DLL elements in the series. This reduces the amount of phase error on these output clocks when compared to DLL elements that do not have outputs coupled to each other.
System and method for reducing cross coupling effects
A device includes a first driver circuit coupled to a first bus line, where the first driver circuit includes a first delay element. The first delay element is configured to receive a first input signal and generate a first output signal. The first output signal transitions logic levels after a first delay period when the first input signal transitions from a logic high level to a logic low level. The first output signal transitions logic levels after a second delay period when the first input signal transitions from the logic low level to the logic high level. The first delay element includes a sense amplifier. The first driver circuit is configured to transmit the first output signal over the first bus line. The device also includes a second driver circuit configured to transmit a second output signal over a second bus line.
System and method for reducing cross coupling effects
A device includes a first driver circuit coupled to a first bus line, where the first driver circuit includes a first delay element. The first delay element is configured to receive a first input signal and generate a first output signal. The first output signal transitions logic levels after a first delay period when the first input signal transitions from a logic high level to a logic low level. The first output signal transitions logic levels after a second delay period when the first input signal transitions from the logic low level to the logic high level. The first delay element includes a sense amplifier. The first driver circuit is configured to transmit the first output signal over the first bus line. The device also includes a second driver circuit configured to transmit a second output signal over a second bus line.
METHOD FOR SYNCHRONOUSLY DISTRIBUTING A DIGITAL SIGNAL OVER N IDENTICAL ADJACENT BLOCKS OF AN INTEGRATED CIRCUIT
The invention proposes a method for distributing a signal to each block B.sub.j of a series of N adjacent blocks of identical design in an electronic circuit. It proposes, in an identical fashion for each of the N blocks, placing a timing delay circuit MUX-DEL.sub.j on the path for conveying a signal S.sub.c from the input INc.sub.j of the block to an internal electrical node Nd.sub.j of the block for this signal S.sub.c; providing for the timing delay circuit to supply N delayed signals corresponding to N different timing delays Δf.sub.1 , . . . Δf.sub.j, . . . Δf.sub.N separated by an increment of elementary duration Δt that corresponds to the elementary delay Δt for transit of a block introduced into a conductive line; and selecting the delayed signal corresponding to the applicable timing delay according to the block in question, by means of an index signal propagated through the N blocks, and which is incremented or decremented on passage through each block.
Arbitrary Delay Buffer
A signal may be arbitrarily delayed in discrete steps by an arbitrary delay buffer having an analog delay and a digital delay. An analog delay may have a number of selectable delay stages (e.g. ring oscillator with VCDL stages). A digital delay may have rising and falling edge detectors, resettable ring oscillators that oscillate in response to rising or falling edges and counters to count oscillations and generate rising and falling edge delay signals when oscillation counts reach rising and falling edge delay counts. A resettable ring oscillator may have a resettable stage (e.g. VCDL) that may be enabled and disabled. Selection of one or both digital and analog delays and respective delay times may be based on one or more characteristics. For example, an analog delay may delay an input signal or a delayed input signal received from the digital delay based on input signal frequency or total delay.
DEVICE FOR CORRECTING MULTI-PHASE CLOCK SIGNAL
A device for correcting a multi-phase clock signal includes a first duty ratio adjusting circuit (DRAC) to adjust a duty ratio of a first clock signal; a variable delay line (VDL) delaying a second clock signal; a second DRAC adjusting a duty ratio of the VDL output; first and second differential clock generating circuits (DFCGs) generating differential signals from first and second DRAC outputs, respectively; an edge combining circuit combining edges of outputs from the DFCGs; a duty ratio detecting circuit (DRDC) detecting a duty ratio of a first DRAC output or a first DFCG output in a first mode and of an edge combining circuit output in a second mode; a first control circuit controlling the first and second DRACs using a DRDC output in the first mode; and a second control circuit controlling the VDL using the DRDC output in the second mode.