Techniques relating to oscillators
    1.
    发明授权
    Techniques relating to oscillators 有权
    与振荡器有关的技术

    公开(公告)号:US08035453B1

    公开(公告)日:2011-10-11

    申请号:US12577568

    申请日:2009-10-12

    IPC分类号: H03K3/03 H03L1/00 H03L7/099

    摘要: An oscillator circuit includes differential variable delay circuits coupled together to form a ring oscillator. Each of the differential variable delay circuits has first and second inputs and first, second, third, and fourth transistors. A constant supply voltage is provided to sources of the first and the second transistors in each of the differential variable delay circuits. A variable supply voltage is provided to sources of the third and the fourth transistors in each of the differential variable delay circuits. Gates of the first and the third transistors are coupled to the first input. Gates of the second and the fourth transistors are coupled to the second input. The oscillator circuit generates a periodic output signal having a frequency that varies based on changes in the variable supply voltage.

    摘要翻译: 振荡器电路包括耦合在一起以形成环形振荡器的差分可变延迟电路。 每个差分可变延迟电路具有第一和第二输入以及第一,第二,第三和第四晶体管。 在每个差分可变延迟电路中,向第一和第二晶体管的源极提供恒定的电源电压。 可变电源电压被提供给每个差分可变延迟电路中的第三和第四晶体管的源极。 第一和第三晶体管的栅极耦合到第一输入端。 第二和第四晶体管的栅极耦合到第二输入端。 振荡器电路产生具有基于可变电源电压的变化而变化的频率的周期性输出信号。

    Increased sensitivity and reduced offset variation in high data rate HSSI receiver
    2.
    发明授权
    Increased sensitivity and reduced offset variation in high data rate HSSI receiver 有权
    在高数据速率HSSI接收机中增加灵敏度和减少偏移变化

    公开(公告)号:US07777526B2

    公开(公告)日:2010-08-17

    申请号:US12134777

    申请日:2008-06-06

    IPC分类号: H03K19/094

    摘要: Signal offset variation caused by transistor variation/mismatch in integrated circuits may be reduced. In one embodiment, a buffer circuit has variable-valued circuit elements. Offset variation measurements are made and the variable-valued circuit elements are calibrated to reduce the measured offset variation. In another embodiment, each amplifying stage of a multi-stage buffer provides variable gain. The total DC gain of the cascade is distributed unevenly across the stages, with more DC gain being provided by amplifier stages at the beginning of the cascade than at the end. An additional pre-amplifier stage can also be provided at the beginning of the cascade.

    摘要翻译: 集成电路中晶体管变化/失配引起的信号偏移变化可能会降低。 在一个实施例中,缓冲电路具有可变值电路元件。 进行偏移变化测量,并校准可变值电路元件以减少测量的偏移变化。 在另一个实施例中,多级缓冲器的每个放大级提供可变增益。 级联的总直流增益不均匀地分布在整个级中,在级联开始时比放大器级提供更多的直流增益。 在级联开始时也可以提供一个额外的前级放大器级。

    Programmable receiver equalization circuitry and methods
    3.
    发明授权
    Programmable receiver equalization circuitry and methods 有权
    可编程接收机均衡电路和方法

    公开(公告)号:US07697600B2

    公开(公告)日:2010-04-13

    申请号:US11182658

    申请日:2005-07-14

    IPC分类号: H03H7/30

    摘要: Data signals transmitted over transmission media suffer from attenuation caused by the transmission media. Equalization circuitry may be provided to compensate for attenuation caused by the transmission media. Equalization circuitry may include multiple stages arranged in series to allow the frequency responses of the stages to aggregate together. Each stage may be programmable to insert a zero, which causes the frequency response of the stage to increase in magnitude by 20 dB/decade. The frequency location of the zero may also be programmable to allow each stage to contribute a certain amount of gain for a specific frequency. Each stage may also be programmable to determine the location of poles for reduction of high frequency noise and cross-talk cancellation.

    摘要翻译: 通过传输介质传输的数据信号遭受由传输介质引起的衰减。 可以提供均衡电路以补偿由传输介质引起的衰减。 均衡电路可以包括串联布置的多个级,以允许级的频率响应聚合在一起。 每个级可以是可编程的,以插入一个零,这使得该级的频率响应在幅度上增加20dB /十倍。 零的频率位置也可以是可编程的,以允许每个级对特定频率贡献一定量的增益。 每个阶段也可以被编程以确定用于降低高频噪声和串扰取消的极点的位置。

    Programmable receiver equalization circuitry and methods
    4.
    发明申请
    Programmable receiver equalization circuitry and methods 有权
    可编程接收机均衡电路和方法

    公开(公告)号:US20070014344A1

    公开(公告)日:2007-01-18

    申请号:US11182658

    申请日:2005-07-14

    IPC分类号: H03H7/30

    摘要: Data signals transmitted over transmission media suffer from attenuation caused by the transmission media. Equalization circuitry may be provided to compensate for attenuation caused by the transmission media. Equalization circuitry may include multiple stages arranged in series to allow the frequency responses of the stages to aggregate together. Each stage may be programmable to insert a zero, which causes the frequency response of the stage to increase in magnitude by 20 dB/decade. The frequency location of the zero may also be programmable to allow each stage to contribute a certain amount of gain for a specific frequency. Each stage may also be programmable to determine the location of poles for reduction of high frequency noise and cross-talk cancellation.

    摘要翻译: 通过传输介质传输的数据信号遭受由传输介质引起的衰减。 可以提供均衡电路以补偿由传输介质引起的衰减。 均衡电路可以包括串联布置的多个级,以允许级的频率响应聚合在一起。 每个级可以是可编程的,以插入一个零,这使得该级的频率响应在幅度上增加20dB /十倍。 零的频率位置也可以是可编程的,以允许每个级对特定频率贡献一定量的增益。 每个阶段也可以被编程以确定用于降低高频噪声和串扰取消的极点的位置。

    Voltage-controlled oscillator methods and apparatus
    5.
    发明授权
    Voltage-controlled oscillator methods and apparatus 有权
    压控振荡器的方法和装置

    公开(公告)号:US08120429B1

    公开(公告)日:2012-02-21

    申请号:US12787722

    申请日:2010-05-26

    IPC分类号: H03L7/00 H03K3/03

    摘要: Methods and apparatus are provided for generating a clock signal with relatively high bandwidth and relatively low phase noise. A circuit of the invention can include a pair of transistors serially coupled between a signal of relatively high voltage and a source of relatively low voltage, where a voltage of the signal of relatively high voltage can vary according to a voltage of a variable control signal. A gate of one of the pair of transistors can be coupled to an input clock signal, and an output node between the pair of transistors can be coupled to an output clock signal. The circuit can also include a third transistor, whose drain and source are coupled to the output clock signal, and whose gate can be coupled to a gear input signal. This circuit can advantageously operate under at least two different gears, each with different bandwidth and phase noise characteristics.

    摘要翻译: 提供了用于产生具有相对较高带宽和相对较低相位噪声的时钟信号的方法和装置。 本发明的电路可以包括串联耦合在相对高电压的信号和相对低电压的源之间的一对晶体管,其中相对高电压的信号的电压可以根据可变控制信号的电压而变化。 一对晶体管中的一个的栅极可以耦合到输入时钟信号,并且该对晶体管之间的输出节点可以耦合到输出时钟信号。 电路还可以包括第三晶体管,其漏极和源极耦合到输出时钟信号,并且其栅极可以耦合到齿轮输入信号。 该电路可以有利地在至少两个不同的齿轮下运行,每个齿轮具有不同的带宽和相位噪声特性。

    Signal amplitude detection circuitry without pattern dependencies for high-speed serial links
    6.
    发明授权
    Signal amplitude detection circuitry without pattern dependencies for high-speed serial links 有权
    信号幅度检测电路,无高速串行链路的模式相关性

    公开(公告)号:US07576570B1

    公开(公告)日:2009-08-18

    申请号:US11508607

    申请日:2006-08-22

    IPC分类号: H03K5/153

    CPC分类号: H03K5/153 H03K5/24

    摘要: Precision amplitude detection circuitry without pattern dependencies is provided that includes rectifier circuitry to output a rectified voltage signal and delay circuitry to send one or more delayed or phase-shifted versions of a differential signal input to the rectifier circuitry. The delayed versions of the differential signal input may be delayed in order to reduce or eliminate the dips in the input seen by the rectifier. This may help correct for low rectified voltage levels. The signal amplitude detection circuitry of the present invention may be incorporated on the input pin of any programmable logic resource and may be included in communication circuitry of a PLD. The precision amplitude detection circuitry may operate in the Gbps (gigabit per second) range.

    摘要翻译: 提供了没有图形相关性的精密幅度检测电路,其包括整流电路,用于输出整流电压信号和延迟电路,以将一个或多个差分信号输入的延迟或相移版本发送到整流器电路。 可以延迟差分信号输入的延迟版本,以便减少或消除由整流器看到的输入中的下降。 这可能有助于校正低整流电压电平。 本发明的信号幅度检测电路可以结合在任何可编程逻辑资源的输入引脚上,并且可以被包括在PLD的通信电路中。 精度幅度检测电路可以以Gbps(千兆位/秒)范围工作。

    Digital adaptation circuitry and methods for programmable logic devices
    7.
    发明授权
    Digital adaptation circuitry and methods for programmable logic devices 有权
    用于可编程逻辑器件的数字适配电路和方法

    公开(公告)号:US07920621B2

    公开(公告)日:2011-04-05

    申请号:US11522284

    申请日:2006-09-14

    IPC分类号: H03H7/30

    CPC分类号: H04L25/03885

    摘要: Equalization of an incoming data signal can be controlled by sampling that signal at times when data values in that signal should be stable (“data samples”) and when that signal should be in transition between successive data values that are different (“transition samples”). A transition sample that has been taken between two successive differently valued data samples is compared to a reference value (which can be one of those two data samples). The result of this comparison can be used as part of a determination as to whether to increase or decrease equalization of the incoming data signal.

    摘要翻译: 输入数据信号的均衡可以通过在该信号中的数据值应当稳定(“数据采样”)的时候对该信号进行采样来控制,并且当该信号应该在不同的连续数据值(“转换样本” )。 将已经在两个连续的不同值数据样本之间拍摄的转换样本与参考值(可以是这两个数据样本之一)进行比较。 该比较的结果可以用作关于是否增加或减少输入数据信号的均衡的确定的一部分。

    Adaptive equalization methods and apparatus for programmable logic devices
    8.
    发明授权
    Adaptive equalization methods and apparatus for programmable logic devices 有权
    用于可编程逻辑器件的自适应均衡方法和装置

    公开(公告)号:US07773668B1

    公开(公告)日:2010-08-10

    申请号:US10762864

    申请日:2004-01-21

    IPC分类号: H03H7/30 H03H7/40

    摘要: A programmable logic device is provided with adaptive equalization circuitry that is programmable in one or more respects. Examples of the programmable aspects of the equalization circuitry are (1) the number of taps used, (2) whether integer or fractional spaced taps are used, (3) what starting values are used in the computation of coefficient values, (4) whether satisfactory coefficient values are computed only once or on an on-going basis, (5) whether an error signal is generated using a decision directed algorithm or using a training pattern, (6) what training pattern (if any) is used, and/or (7) the location of the sampling point in the bit period of the signal to be equalized.

    摘要翻译: 可编程逻辑器件设置有可在一个或多个方面可编程的自适应均衡电路。 均衡电路的可编程方面的示例是(1)使用的抽头数量,(2)是否使用整数或分数间隔抽头,(3)在系数值的计算中使用什么起始值,(4)是否 (5)是否使用决策导向算法或使用训练模式生成错误信号,(6)使用何种训练模式(如果有的话)和/ 或者(7)要被均衡的信号的位周期内的采样点的位置。

    Programmable digital equalization control circuitry and methods
    9.
    发明授权
    Programmable digital equalization control circuitry and methods 失效
    可编程数字均衡控制电路和方法

    公开(公告)号:US07760799B2

    公开(公告)日:2010-07-20

    申请号:US11238365

    申请日:2005-09-28

    IPC分类号: H03H7/30 H03H7/40 H03K5/159

    CPC分类号: H03G3/3089 H04L25/03885

    摘要: Equalization circuitry may be used to compensate for the attenuation of a data signal caused by a transmission medium. The control circuitry for the equalization circuitry may generate control inputs for equalization stages that control the amount of gain provided to the data signal. A comparator may determine whether the gain from the equalization circuitry is less than or more than the desired amount of gain. A programmable up/down counter may adjust the counter value based on the output of the comparator. The counter value may be converted into one or more analog voltages using one or more digital-to-analog converters. These analog voltages may be provided to the equalization stages as control inputs. The control circuitry may also include hysteresis circuitry that prevents the counter value from being adjusted when the gain produced by the equalization stages is close to the desired amount of gain.

    摘要翻译: 均衡电路可用于补偿由传输介质引起的数据信号的衰减。 用于均衡电路的控制电路可以产生用于控制提供给数据信号的增益量的均衡级的控制输入。 比较器可以确定来自均衡电路的增益是否小于或大于期望的增益量。 可编程上/下计数器可以根据比较器的输出来调整计数器值。 可以使用一个或多个数模转换器将计数器值转换成一个或多个模拟电压。 这些模拟电压可以作为控制输入提供给均衡级。 控制电路还可以包括滞后电路,当由均衡级产生的增益接近期望的增益量时,阻止计数器值被调整。

    High-speed serial interface circuitry for programmable logic device integrated circuits
    10.
    发明授权
    High-speed serial interface circuitry for programmable logic device integrated circuits 有权
    用于可编程逻辑器件集成电路的高速串行接口电路

    公开(公告)号:US07688106B1

    公开(公告)日:2010-03-30

    申请号:US11712609

    申请日:2007-02-27

    IPC分类号: H03K19/173

    CPC分类号: H03K19/17744

    摘要: High-speed serial interface (“HSSI”) transceiver circuitry (e.g., on a programmable logic device (“PLD”) integrated circuit) includes input buffer circuitry with adaptive equalization capability. The transceiver circuitry also includes an output driver, which may include pre-emphasis capability (preferably controllably settable). Selectively usable loop-back circuitry is provided for allowing the output signal of the input buffer to be applied substantially directly to the output driver. The loop-back circuitry may include a loop-back driver, which may be turned on substantially only when needed for loop-back operations.

    摘要翻译: 高速串行接口(“HSSI”)收发器电路(例如,在可编程逻辑器件(“PLD”)集成电路上)包括具有自适应均衡能力的输入缓冲器电路。 收发器电路还包括输出驱动器,其可以包括预加重功能(优选可控地设置)。 提供了可选择的环回电路,用于使输入缓冲器的输出信号基本上直接施加到输出驱动器。 环回电路可以包括环回驱动器,其可以基本上仅在环回操作需要时被导通。