专利快速检索-快速检索全球专利，免费商用专利数据库-IPRDB

1. 发明授权

US08704559B2 Method and system for synchronizing the phase of a plurality of divider circuits in a local-oscillator signal path 有权
标题翻译：用于使本地振荡器信号路径中的多个分频器电路的相位同步的方法和系统
公开(公告)号：US08704559B2
公开(公告)日：2014-04-22
申请号：US13401706
申请日：2012-02-21
申请人： Keng Leong Fong , John Wong , Jenwei Ko
发明人： Keng Leong Fong , John Wong , Jenwei Ko
IPC分类号： H03L7/00
CPC分类号： H03L7/00 , H03K23/425 , H03K23/665
摘要： A method and system for synchronizing the output signal phase of a plurality of frequency divider circuits in a local-oscillator (LO) or clock signal path is disclosed. The LO path includes a plurality of frequency divider circuits and a LO buffer for receiving a LO signal coupled to the plurality of frequency divider circuits. The method and system comprise adding offset voltage and setting predetermined state to each of the frequency divider circuits; and enabling the frequency divider circuits. The method and system includes enabling the LO buffer to provide the LO signal to the frequency divider circuits after they have been enabled. When the LO signal drives each of the frequency divider circuits, each of the frequency divider circuits starts an operation. Finally the method and system comprise removing the offset voltage from each of the frequency divider circuits to allow them to effectively drive other circuits.
摘要翻译：公开了一种用于使本地振荡器（LO）或时钟信号路径中的多个分频器电路的输出信号相位同步的方法和系统。 LO路径包括多个分频器电路和LO缓冲器，用于接收耦合到多个分频器电路的LO信号。该方法和系统包括增加偏移电压并将预定状态设置到每个分频器电路; 并启用分频器电路。该方法和系统包括使得LO缓冲器在它们被使能之后向分频器电路提供LO信号。当LO信号驱动每个分频器电路时，每个分频器电路开始一个操作。最后，该方法和系统包括从每个分频器电路去除偏移电压，以允许它们有效地驱动其它电路。

2. 发明授权

US08022740B2 Fast-response phase-locked loop charge-pump driven by low voltage input 有权
标题翻译：由低电压输入驱动的快速响应锁相环电荷泵
公开(公告)号：US08022740B2
公开(公告)日：2011-09-20
申请号：US12718935
申请日：2010-03-05
申请人： I-chang Wu , Chungwen Lo , Keng Leong Fong
发明人： I-chang Wu , Chungwen Lo , Keng Leong Fong
IPC分类号： H03L7/06
CPC分类号： H03L7/0896
摘要： Phase-locked loop charge pump driven by low voltage input. In one aspect, a phase-locked loop circuit includes a phase frequency detector operating at a low voltage and providing low-voltage sourcing control signals and low-voltage sinking control signals at the low voltage. A charge pump operates at a high voltage and includes a sourcing control circuit coupled to the low-voltage sourcing control signals and selectively causing the charge pump to source the sourcing current to an output of the charge pump based on the low-voltage sourcing control signals. The charge pump also includes a sinking control circuit that receives the low-voltage sinking control signals and selectively causes the charge pump to sink the sinking current from the output of the charge pump based on the low-voltage sinking control signals.
摘要翻译：锁相环电荷泵由低电压输入驱动。一方面，锁相环电路包括在低电压下工作的相位频率检测器，并在低电压下提供低电压源控制信号和低电压吸收控制信号。电荷泵以高电压工作，并且包括耦合到低电压源控制信号的源极控制电路，并且基于低电压源控制信号选择性地使电荷泵将源电流源源于电荷泵的输出。电荷泵还包括一个吸收控制电路，其接收低电压吸收控制信号，并且基于低压吸收控制信号选择性地使电荷泵从电荷泵的输出吸收吸收电流。

3. 发明授权

US07348861B1 Method and apparatus for a crystal oscillator to achieve fast start-up time, low power and frequency calibration 有权
标题翻译：用于晶体振荡器的方法和装置，以实现快速启动时间，低功率和频率校准
公开(公告)号：US07348861B1
公开(公告)日：2008-03-25
申请号：US11095630
申请日：2005-03-31
申请人： I-chang Wu , Chung Wen Lo , Keng Leong Fong
发明人： I-chang Wu , Chung Wen Lo , Keng Leong Fong
IPC分类号： H03B5/32 , H03L5/00
CPC分类号： H03B5/366 , H03L3/00
摘要： One embodiment of the present invention includes a frequency generation circuit including a control module, an oscillator circuit coupled to the control module, the oscillator circuit having a start-up time defined by the time required to reach a desired frequency. The oscillator circuit includes an amplifier having an input and an output and being programmably-alterable by the control module, a first capacitor coupled to the input of the amplifier and being programmably-alterable, in capacitance, by the control module, a second capacitor coupled to the output of the amplifier, a crystal resonator coupled to the first and second capacitors for generating an output signal having a desired frequency, wherein fast start-up time is achieved.
摘要翻译：本发明的一个实施例包括频率产生电路，其包括控制模块，耦合到控制模块的振荡器电路，振荡器电路具有由达到期望频率所需的时间所限定的启动时间。振荡器电路包括具有输入和输出的放大器，并且可由控制模块编程地改变;第一电容器，耦合到放大器的输入端，并且可由控制模块以电容方式可编程地改变第二电容器耦合耦合到放大器的输出，耦合到第一和第二电容器的晶体谐振器，用于产生具有期望频率的输出信号，其中实现了快速启动时间。

4. 发明授权

US07816983B2 Fast switch for controlling a differential-pair amplifier 有权
标题翻译：用于控制差分对放大器的快速开关
公开(公告)号：US07816983B2
公开(公告)日：2010-10-19
申请号：US12013312
申请日：2008-01-11
申请人： Keng Leong Fong
发明人： Keng Leong Fong
IPC分类号： H03F1/14
CPC分类号： H03F3/45085 , H03F3/72 , H03F2203/45506 , H03F2203/7203
摘要： A differential-pair amplifier comprising a transistor pair. The differential-pair amplifier includes a current source coupled to the transistor pair for providing a bias current to the transistor pair. The differential-pair amplifier also includes a switching mechanism coupled to the transistor pair for steering the bias current away from the transistor pair when disabling the amplifier operation. A system and method in accordance with the present invention allows fast enabling and disabling of a differential-pair amplifier. This fast switching technique can be used in the signal paths where the switching time is critical.
摘要翻译：一种包括晶体管对的差分对放大器。差分对放大器包括耦合到晶体管对的电流源，用于向晶体管对提供偏置电流。差分对放大器还包括耦合到晶体管对的开关机构，用于在禁用放大器操作时将偏置电流转移离开晶体管对。根据本发明的系统和方法允许差分对放大器的快速启用和禁用。这种快速切换技术可用于切换时间至关重要的信号路径。

5. 发明授权

US07705641B2 Fast response phase-locked loop charge-pump driven by low voltage input 有权
标题翻译：由低电压输入驱动的快速响应锁相环电荷泵
公开(公告)号：US07705641B2
公开(公告)日：2010-04-27
申请号：US12108329
申请日：2008-04-23
申请人： I-chang Wu , Chungwen Lo , Keng Leong Fong
发明人： I-chang Wu , Chungwen Lo , Keng Leong Fong
IPC分类号： H03L7/06
CPC分类号： H03L7/0896
摘要： Phase-locked loop charge pump driven by low voltage input. In one aspect, a charge pump for a phase-locked loop circuit includes a sourcing current transistor providing a sourcing current, wherein the sourcing current transistor is coupled to a high-voltage operating voltage supply. A sourcing control circuit uses low-voltage sourcing control signals to selectively cause the charge pump to source the sourcing current to an output of the charge pump, and a sinking control circuit uses low-voltage sinking control signals to selectively cause the charge pump to sink the sinking current from the output.
摘要翻译：锁相环电荷泵由低电压输入驱动。一方面，用于锁相环电路的电荷泵包括提供源极电流的源极电流晶体管，其中所述源极电流晶体管耦合到高压工作电压源。源控制电路使用低电压源控制信号来选择性地使电荷泵将源电流源源于电荷泵的输出，并且下沉控制电路使用低电压吸收控制信号来选择性地使电荷泵吸收来自输出的下沉电流。

6. 发明授权

US06211737B1 Variable gain amplifier with improved linearity 有权
标题翻译：具有改善线性度的可变增益放大器
公开(公告)号：US06211737B1
公开(公告)日：2001-04-03
申请号：US09354603
申请日：1999-07-16
申请人： Keng Leong Fong
发明人： Keng Leong Fong
IPC分类号： H03G312
CPC分类号： H03F3/72 , H03F1/22 , H03F1/223 , H03F1/32 , H03F3/19 , H03F2200/294 , H03F2200/372 , H03G1/0023 , H03G1/0088
摘要： A circuit includes a transconductance stage which converts an input signal power into a signal current and supplies it to an output of the circuit. A current diverting circuit branch is coupled to selectively divert the current from the transconductance stage away from the output. A feedback network feeds back a portion of the current diverted away from the output to the input of the transconductance stage. When implemented as a variable gain amplifier, the current diverting branch functions to change a gain of the circuit from a high level to one or more lower levels. The feeding back of a portion of the diverted current to the input improves the linearity of the circuit in the lower gain mode(s).
摘要翻译：电路包括将输入信号功率转换为信号电流并将其提供给电路的输出的跨导级。耦合电流转向电路支路以选择性地将来自跨导级的电流转移离开输出。反馈网络将从输出端转移的电流的一部分反馈到跨导级的输入端。当实现为可变增益放大器时，电流转移支路用于将电路的增益从高电平改变到一个或多个较低电平。将一部分转向电流反馈到输入端改善了较低增益模式下电路的线性度。

7. 发明授权

US6147559A Noise figure and linearity improvement technique using shunt feedback 失效
标题翻译：使用分流反馈的噪声系数和线性度改进技术
公开(公告)号：US6147559A
公开(公告)日：2000-11-14
申请号：US126242
申请日：1998-07-30
申请人： Keng Leong Fong
发明人： Keng Leong Fong
IPC分类号： H03D7/14 , H03F1/22 , H03F1/26 , H03F1/32 , H03F1/34 , H03F3/68
CPC分类号： H03F1/22 , H03F1/32 , H03F2200/294 , H03F2200/372
摘要： A shunt-feedback technique is provided for improving noise figure and linearity of electronic circuits, such as amplifiers and mixers. An input common-emitter transconductance stage of an electronic circuit has a transistor, and a degeneration impedance provided between the emitter of the transistor and a ground terminal. A feedback capacitor is connected between the collector and the base of the transistor. A feedback resistor is coupled between the collector of the transconductance stage transistor and the emitter of a transistor in the next stage of the electronic circuit. The feedback capacitor and the feedback resistor form a shunt-feedback network.
摘要翻译：提供了分流反馈技术，用于改善诸如放大器和混频器之类的电子电路的噪声系数和线性度。电子电路的输入共 - 发射极跨导级具有晶体管，以及设置在晶体管的发射极与接地端子之间的退化阻抗。反馈电容器连接在晶体管的集电极和基极之间。反馈电阻器耦合在跨导级晶体管的集电极和电子电路的下一级中的晶体管的发射极之间。反馈电容器和反馈电阻器形成分流反馈网络。

8. 发明授权

US5999056A Variable gain amplifier using impedance network 失效
标题翻译：可变增益放大器采用阻抗网络
公开(公告)号：US5999056A
公开(公告)日：1999-12-07
申请号：US107523
申请日：1998-06-30
申请人： Keng Leong Fong
发明人： Keng Leong Fong
IPC分类号： H03F1/08 , H03G1/00 , H03G1/04 , H03G3/10
CPC分类号： H03F1/22 , H03G1/0023 , H03G1/0088
摘要： A circuit includes a transconductance device which converts an input signal voltage to a signal current. An output terminal is coupled to receive signal current from the transconductance device. A gain-control circuit has an impedance network coupled to the output terminal to maintain a constant impedance at the output terminal and selectively steers current from the transconductance device through at least first and second different nodes of the impedance network to vary the current supplied to the output terminal. The circuit has reduced noise figure degradation as compared to known current steering circuits by controlling gain without dumping signal current directly to the supply and without changing the impedance at the output terminal. The circuit is particularly useful in the RF section of radio receivers and transmitters, such as in cellular phones.
摘要翻译：电路包括将输入信号电压转换为信号电流的跨导装置。输出端子被耦合以从跨导装置接收信号电流。增益控制电路具有耦合到输出端子的阻抗网络，以在输出端子处保持恒定的阻抗，并且选择性地引导来自跨导器件的电流通过阻抗网络的至少第一和第二不同节点，以改变提供给输出端子。与已知的电流转向电路相比，通过控制增益而不将信号电流直接转换到电源并且不改变输出端子处的阻抗，该电路降低了噪声系数。该电路在诸如蜂窝电话中的无线电接收机和发射机的RF部分中特别有用。

你已经成功收藏专利！

检索式保存成功!

IPRDB

热门服务

关于我们

友情链接

联系方式