Selective implementation of power management schemes based on detected computer operating environment
    1.
    发明授权
    Selective implementation of power management schemes based on detected computer operating environment 有权
    基于检测到的计算机操作环境选择性实施电源管理方案

    公开(公告)号:US07055047B2

    公开(公告)日:2006-05-30

    申请号:US10410089

    申请日:2003-04-09

    IPC分类号: G06F1/32

    摘要: Detecting a radio frequency (RF) environment around a computer and using a power management scheme for an RF user input device being used by the computer system. If the computer system is in a single user environment, a power management scheme may be used to conserve power on the RF user input device. If the computer system is in a multi-user environment, a power management scheme may be used to minimize interference between neighboring computer systems by minimizing the signal strength of the RF signal from the RF user input device and the RF signal from the computer system.

    摘要翻译: 检测计算机周围的射频(RF)环境,并为计算机系统正在使用的RF用户输入设备使用电源管理方案。 如果计算机系统处于单个用户环境中,则可以使用电源管理方案来节省RF用户输入设备上的功率。 如果计算机系统处于多用户环境中,则可以使用功率管理方案来最小化来自RF用户输入设备的RF信号的信号强度和来自计算机系统的RF信号来最小化相邻计算机系统之间的干扰。

    Crystal oscillator with control feedback to maintain oscillation
    2.
    发明授权
    Crystal oscillator with control feedback to maintain oscillation 有权
    晶振与控制反馈保持振荡

    公开(公告)号:US06819196B2

    公开(公告)日:2004-11-16

    申请号:US10366177

    申请日:2003-02-13

    IPC分类号: H03B532

    CPC分类号: H03B5/36 H03L5/00

    摘要: An oscillator circuit. In one embodiment, the oscillator includes a gain circuit, an envelope detector, and an amplitude comparison circuit. The trans-conductance circuit is configured to amplify a periodic signal produced by a crystal. Amplitude peaks of the periodic signal may be detected in the envelope detector, which may determine an average amplitude value based on the detected peaks. The average amplitude value may be compared to a DC voltage value in an amplitude comparison circuit. The DC voltage value may include both a DC average of the periodic signal as well as a predetermined DC offset value. The gain circuit may adjust the level of amplification of the periodic signal based on a feedback signal in order to ensure that the oscillator produces a periodic output signal at a desired level so as to insure oscillation and the minimum use of current to achieve oscillations.

    摘要翻译: 振荡电路。 在一个实施例中,振荡器包括增益电路,包络检测器和振幅比较电路。 跨导电路被配置为放大由晶体产生的周期信号。 可以在包络检测器中检测周期信号的幅度峰值,其可以基于检测到的峰值来确定平均振幅值。 平均振幅值可以与幅度比较电路中的直流电压值进行比较。 DC电压值可以包括周期信号的DC平均值以及预定的DC偏移值。 增益电路可以基于反馈信号来调节周期信号的放大电平,以便确保振荡器产生期望电平的周期性输出信号,从而确保振荡和电流的最小使用以实现振荡。

    Self calibrating VCO correction circuit and method of operation
    3.
    发明授权
    Self calibrating VCO correction circuit and method of operation 有权
    自校准VCO校正电路及操作方法

    公开(公告)号:US6133797A

    公开(公告)日:2000-10-17

    申请号:US363221

    申请日:1999-07-30

    摘要: A PLL system (10) includes a PFD (24) that receives a reference clock signal (REF CLK) and a feedback clock signal (FBK CLK). The PFD (24) generates an analog signal (TUNE) based on the phase and frequency relationship of the reference and feedback clock signals. The PFD (24) also generates a clock signal based on two PI phase slips for clocking a counter (70). The analog signal is compared against an upper and lower reference voltage in a threshold detect circuit (34) and the signals UP and DOWN supplied to the counter (70). The counter (70) provides a count value that controls the resonant frequency generated by a tank circuit (73). The tuning range of an oscillator (18) is extended by changing the capacitance of the tank circuit (73).

    摘要翻译: PLL系统(10)包括接收参考时钟信号(REF CLK)和反馈时钟信号(FBK CLK)的PFD(24)。 PFD(24)基于参考和反馈时钟信号的相位和频率关系产生模拟信号(TUNE)。 PFD(24)还基于用于对计数器(70)计时的两个PI相位差产生时钟信号。 将模拟信号与阈值检测电路(34)中的上限和下限参考电压以及提供给计数器(70)的信号UP和DOWN进行比较。 计数器(70)提供控制由电路(73)产生的谐振频率的计数值。 振荡器(18)的调谐范围通过改变储能电路(73)的电容来延长。

    Amplifier circuit with amplitude and phase correction and method of
operation
    5.
    发明授权
    Amplifier circuit with amplitude and phase correction and method of operation 有权
    放大器电路具有幅度和相位校正和操作方法

    公开(公告)号:US6150881A

    公开(公告)日:2000-11-21

    申请号:US317924

    申请日:1999-05-25

    IPC分类号: H03F3/45

    摘要: A correction circuit (10) includes a transistor (30) that generates a feedback signal for equalizing the amplitude and adjusting the phase of the output signals (V.sub.OUT- and V.sub.OUT+) that are provided at the output of the variable gain amplifier (10). The base terminal of the transistor (30) receives a summed value of the output signals (V.sub.OUT- and V.sub.OUT+). The summed value is inverted and fed back to the differential transistors (12 and 14) and combined with the output signals (V.sub.OUT- and V.sub.OUT+). The output signals (V.sub.OUT- and V.sub.OUT+) have a proper amplitude and phase relationship when the summed value is substantially zero.

    摘要翻译: 校正电路(10)包括晶体管(30),其产生用于均衡振幅并且调整在可变增益放大器(10)的输出处提供的输出信号(VOUT-和VOUT +)的相位的反馈信号。 晶体管(30)的基极端子接收输出信号(VOUT-和VOUT +)的相加值。 相加的值被反相并反馈到差分晶体管(12和14),并与输出信号(VOUT-和VOUT +)组合。 当总和值基本为零时,输出信号(VOUT-和VOUT +)具有适当的幅度和相位关系。

    Circuit and method of extending the linear range of a phase frequency
detector
    6.
    发明授权
    Circuit and method of extending the linear range of a phase frequency detector 有权
    扩展相位频率检测器的线性范围的电路和方法

    公开(公告)号:US6100721A

    公开(公告)日:2000-08-08

    申请号:US241669

    申请日:1999-02-01

    摘要: A wireless communication system (10) uses a phase detector (28) having a first pair of flip-flops (50, 56) for detecting the phase difference between an input frequency and a reference frequency. The first pair of flip-flops control current sources (66, 70) in the charge pump of the phase detector to modulate the error signal. A second pair of flip-flops (52, 58) detect when the input frequency is more than 2.pi. ahead of or behind the reference frequency. The second pair of flip-flops increment and decrement a counter (54) which in turn controls additional current sources (78-88) in the charge pump. The additional current sources extend the linear operating range of the error signal when the phase error exceeds .+-.2.pi..

    摘要翻译: 无线通信系统(10)使用具有用于检测输入频率和参考频率之间的相位差的第一对触发器(50,56)的相位检测器(28)。 第一对触发器控制相位检测器的电荷泵中的电流源(66,70),以调制误差信号。 第二对触发器(52,58)检测输入频率何时超过参考频率之前或之后的2π。 第二对触发器增加和减少计数器(54),反过来控制电荷泵中的附加电流源(78-88)。 当相位误差超过+/- 2 pi时,额外的电流源扩展了误差信号的线性工作范围。

    Variable phase shifter and method
    7.
    发明授权
    Variable phase shifter and method 失效
    可变移相器和方法

    公开(公告)号:US5926052A

    公开(公告)日:1999-07-20

    申请号:US908827

    申请日:1997-08-08

    CPC分类号: H03H11/20 H03D7/165

    摘要: A circuit and method for producing a phase shifted quadrature signal (VOUT) from an in-phase signal (VIN). The in-phase signal (VIN) is applied to the control electrode of a voltage follower (121). The voltage follower (121) has a variable output resistance which combines with a capacitor (123) to delay the input signal (VIN) in accordance with the time constant formed by the variable output resistance and the capacitor (123). The variable output resistance is controlled by adjusting the bias current of the voltage follower (121) with a control signal.

    摘要翻译: 用于从同相信号(VIN)产生相移正交信号(VOUT)的电路和方法。 同相信号(VIN)被施加到电压跟随器(121)的控制电极。 电压跟随器(121)具有可变输出电阻,其与电容器(123)组合以根据由可变输出电阻和电容器(123)形成的时间常数来延迟输入信号(VIN)。 通过用控制信号调节电压跟随器(121)的偏置电流来控制可变输出电阻。

    RF mixer circuit and method of operation
    8.
    发明授权
    RF mixer circuit and method of operation 有权
    射频混频电路及其操作方法

    公开(公告)号:US6104227A

    公开(公告)日:2000-08-15

    申请号:US277867

    申请日:1999-03-29

    IPC分类号: H03D7/14 G06F7/44

    摘要: An RF mixer (10) provides signal gain in a transconductor block (12). A first transistor (36) is sized M times larger than a second transistor (18) to generate the desired signal gain. The gain of the RF mixer (10) is the value M times an output impedance Z.sub.OUT divided by an input impedance Z.sub.IN. A first current (I.sub.40) conducted by the first transistor (36) is matched to a sum of the second current (I.sub.24) conducted by the second transistor (18) and a third current (I.sub.28). The first current is supplied to a first differential transistor pair (46, 48) and the summed current is supplied to a second differential transistor pair (56, 58) to provide balance in switching circuit (50).

    摘要翻译: RF混频器(10)在跨导体块(12)中提供信号增益。 第一晶体管(36)的尺寸大于第二晶体管(18)的M倍,以产生期望的信号增益。 RF混频器(10)的增益是输出阻抗ZOUT除以输入阻抗ZIN的值M。 由第一晶体管(36)传导的第一电流(I40)与由第二晶体管(18)传导的第二电流(I24)和第三电流(I28)的和相匹配。 将第一电流提供给第一差分晶体管对(46,48),并将求和的电流提供给第二差分晶体管对(56,58),以在开关电路(50)中提供平衡。

    Amplifier and method of canceling distortion by combining hyperbolic
tangent and hyperbolic sine transfer functions
    9.
    发明授权
    Amplifier and method of canceling distortion by combining hyperbolic tangent and hyperbolic sine transfer functions 失效
    通过组合双曲正切和双曲正弦传递函数来消除失真的放大器和方法

    公开(公告)号:US5942939A

    公开(公告)日:1999-08-24

    申请号:US88002

    申请日:1998-06-01

    CPC分类号: H03F1/3211

    摘要: A differential amplifier (10) receives a differential input signal (V.sub.IN). The input signal is attenuated by a first attenuator (12) and applied to a tan h amplifier (16). The input signal is also attenuated by a second attenuator (14) and applied to a sin h amplifier (18). The input signals to the tan h amplifier and sin h amplifier are independently attenuated. The transfer functions of the tan h amplifier and the sin h amplifier each have a linear region and a non-linear region. The output of the tan h amplifier and the sin h amplifier are summed (26) so that the non-linear region of the tan h amplifier cancels with the non-linear region of the sin h amplifier. The overall transfer function of the differential amplifier is linear over a wide range of input signal amplitudes by the cancellation of the non-linear regions.

    摘要翻译: 差分放大器(10)接收差分输入信号(VIN)。 输入信号由第一衰减器(12)衰减并施加到tanh放大器(16)。 输入信号也被第二衰减器(14)衰减并施加到sinh放大器(18)。 到tanh放大器和sin h放大器的输入信号被独立衰减。 tanh放大器和sinh放大器的传递函数各具有线性区域和非线性区域。 tanh放大器和sinh放大器的输出相加(26),使得tanh放大器的非线性区域与sinh放大器的非线性区域抵消。 通过非线性区域的消除,差分放大器的整体传递函数在宽范围的输入信号幅度上是线性的。

    Circuit and method for correcting phase error in a multiplier circuit
    10.
    发明授权
    Circuit and method for correcting phase error in a multiplier circuit 失效
    用于校正乘法器电路中的相位误差的电路和方法

    公开(公告)号:US5659263A

    公开(公告)日:1997-08-19

    申请号:US622536

    申请日:1996-03-25

    摘要: A circuit and method for reducing a phase error at the output terminal (48) of a multiplier circuit (41) is provided. The phase error arises when first and second input signals having asymmetric signal paths are multiplied in the multiplier circuit (41). A second multiplier circuit (42) multiplies the in-phase and quadrature signals and produces an output signal at an output terminal (49) which contains the phase error but with the opposite polarity as the phase error produced by the first multiplier circuit (41). The signals at the output terminals (48) and (49) are summed in a summing circuit (43) to produce a third output signal in which the phase error is canceled.

    摘要翻译: 提供了一种用于减小乘法器电路(41)的输出端(48)的相位误差的电路和方法。 当具有不对称信号路径的第一和第二输入信号在乘法器电路(41)中相乘时,产生相位误差。 第二乘法电路(42)将同相和正交信号相乘,并在包含相位误差但具有与第一乘法器电路(41)产生的相位误差相反的极性的输出端子(49)产生输出信号, 。 输出端子(48)和(49)上的信号在求和电路(43)中相加,以产生消除相位误差的第三输出信号。