公开(公告)号：US06819179B2

公开(公告)日：2004-11-16

申请号：US10417318

申请日：2003-04-16

申请人： Muthusamy Kumarasamy Raja ,  Nuntha Kumar Krishnasamy Maniam

发明人： Muthusamy Kumarasamy Raja ,  Nuntha Kumar Krishnasamy Maniam

IPC分类号： H03G310

CPC分类号： H03F3/195 ,  H03F1/223 ,  H03F1/26 ,  H03F1/32 ,  H03F3/72 ,  H03F2200/243 ,  H03F2200/294 ,  H03F2200/372 ,  H03F2200/421 ,  H03F2200/501 ,  H03G1/0088 ,  H03G3/001

摘要： The load of the cascode amplifier is varied by connecting another (secondary) load in parallel with the original load. The secondary load is connected through a MOSFET switch. During the High Gain Mode the MOSFET switch is OFF and the secondary load is electrically isolated from the main load, whereas in the Low Gain Mode the switch is turned ON and the secondary load appears across the primary load, reducing the effective load impedance. The secondary load is AC coupled such that the DC bias current does not pass through the secondary load and hence the Noise Figure (NF) and linearity (IIP3) performance are better in the Low Gain Mode. A number of such switchable loads can be connected across the load to obtain programmability.

摘要翻译： 通过将另一个（次级）负载与原始负载并联连接来改变共源共栅放大器的负载。 次级负载通过MOSFET开关连接。 在高增益模式期间，MOSFET开关为OFF，次级负载与主负载电隔离，而在低增益模式下，开关导通，次级负载跨越主负载，降低有效负载阻抗。 次级负载是交流耦合的，使得DC偏置电流不通过次级负载，因此低增益模式下的噪声系数（NF）和线性度（IIP3）性能更好。 可以跨负载连接多个这种可切换负载以获得可编程性。

公开(公告)号：US06801089B2

公开(公告)日：2004-10-05

申请号：US10139141

申请日：2002-05-03

申请人： Damian Costa ,  Joseph Austin ,  John Groe ,  Michael Farias

发明人： Damian Costa ,  Joseph Austin ,  John Groe ,  Michael Farias

IPC分类号： H03G310

CPC分类号： H03G1/0023 ,  H03F1/22 ,  H03F2200/294 ,  H03F2200/372

摘要： Continuous variable-gain low-noise amplifier. The amplifier continuously adjusts its gain between well-defined high and low values by using a cascode current-steering circuit to partition signal current between two different nodes of an output loading network. A shunt feedback network connected from an intermediate node of the loading network to the input provides negative feedback that linearizes the amplifier as its gain is decreased. The circuit degrades the noise figure at lower gains considerably less than conventional circuits by varying the gain without directly dumping the signal current to the power supply. The circuit produces only small changes in input and output impedances and preserves an improved reverse-isolation cascode characteristic as the gain is controlled.

摘要翻译： 连续可变增益低噪声放大器。 放大器通过使用共源共栅电流转向电路在输出负载网络的两个不同节点之间分配信号电流，在明确的高电平和低电平值之间不断调整其增益。 从负载网络的中间节点连接到输入端的并联反馈网络提供负反馈，使得放大器随着其增益的减小而线性化。 该电路通过改变增益而以比常规电路低得多的噪声系数降低噪声，而不会将信号电流直接转储到电源。 该电路仅在输入和输出阻抗上产生小的变化，并且在增益受到控制时保持改进的反向隔离共源共栅特性。

公开(公告)号：US06784744B2

公开(公告)日：2004-08-31

申请号：US10259222

申请日：2002-09-26

申请人： Larry Martin Tichauer

发明人： Larry Martin Tichauer

IPC分类号： H03G310

CPC分类号： H03G1/0017 ,  H03G3/3036 ,  H03K2217/0018

摘要： Embodiments of the present invention provide an amplifier circuit and method that can be used to save power or reduce distortion in an electronic system, such as a wireless communication system. In one embodiment, the present invention includes an amplifier circuit comprising a transistor having a gate terminal, drain terminal, body terminal, and a load. An input signal has different signal envelopes during different time periods. A control signal coupled to the body terminal is used to change the voltage on the body terminal when the input receives different envelopes. Accordingly, the amplifier can be biased to use less power when lower envelopes are being received. Electronic systems, such as wireless communication systems, can realize advantageous performance enhancements by utilizing the amplifier and other techniques employed by embodiments of the present invention.

摘要翻译： 本发明的实施例提供一种放大器电路和方法，其可以用于节省电力或减少诸如无线通信系统之类的电子系统的失真。 在一个实施例中，本发明包括具有栅极端子，漏极端子，主体端子和负载的晶体管的放大器电路。 输入信号在不同时间段内具有不同的信号包络。 当输入接收到不同的信封时，耦合到身体终端的控制信号用于改变身体终端上的电压。 因此，当接收到较低的信封时，放大器可被偏置以使用更少的功率。 诸如无线通信系统的电子系统可以通过利用放大器和本发明的实施例采用的其它技术来实现有利的性能增强。

公开(公告)号：US06784742B2

公开(公告)日：2004-08-31

申请号：US10189140

申请日：2002-07-03

申请人： Shiro Tsunai ,  Akira Uemura

发明人： Shiro Tsunai ,  Akira Uemura

IPC分类号： H03G310

CPC分类号： H03G1/0088

摘要： A voltage amplifying circuit (100) that may have a selectable gain has been disclosed. Voltage amplifying circuit (100) may include a voltage amplifier (2) and a gain changing unit (7). A gain changing unit (2) may be capable of changing at least one of: a capacitance between a signal input terminal (6) and an input terminal of a voltage amplifier, the capacitance between an input terminal of a voltage amplifier and a ground (or reference potential), and a capacitance between an input and an output terminal (3) of a voltage amplifier. In this way, a gain from a signal input terminal (6) to an output terminal (3) of a voltage amplifier of a voltage amplifying circuit (100) may be changed.

摘要翻译： 已经公开了可以具有可选增益的电压放大电路（100）。 电压放大电路（100）可以包括电压放大器（2）和增益改变单元（7）。 增益改变单元（2）可以能够改变以下至少一个：信号输入端子（6）和电压放大器的输入端子之间的电容，电压放大器的输入端子与地的电容（ 或参考电位），以及电压放大器的输入端和输出端（3）之间的电容。 以这种方式，可以改变从电压放大电路（100）的电压放大器的信号输入端子（6）到输出端子（3）的增益。

公开(公告)号：US06750717B1

公开(公告)日：2004-06-15

申请号：US10222137

申请日：2002-08-15

申请人： Kevin Wesley Kobayashi ,  George W. McIver

发明人： Kevin Wesley Kobayashi ,  George W. McIver

IPC分类号： H03G310

CPC分类号： H03G3/3084

摘要： An apparatus comprising an amplifier and a coupling circuit. The amplifier may be configured to generate an amplified output signal in response to a first input signal and a second input signal. The coupling circuit may be configured to generate the second input signal in response to the first input signal. The coupling circuit may be configured to increase a speed of propagation of the first input signal.

摘要翻译： 一种包括放大器和耦合电路的装置。 放大器可以被配置为响应于第一输入信号和第二输入信号而产生放大的输出信号。 耦合电路可以被配置为响应于第一输入信号而产生第二输入信号。 耦合电路可以被配置成增加第一输入信号的传播速度。

公开(公告)号：US06621346B1

公开(公告)日：2003-09-16

申请号：US09314764

申请日：1999-05-19

申请人： Joseph T. Nabicht ,  Kazi I. Islam ,  Donald C. Richardson ,  Subahashish Mukherjee

发明人： Joseph T. Nabicht ,  Kazi I. Islam ,  Donald C. Richardson ,  Subahashish Mukherjee

IPC分类号： H03G310

CPC分类号： H04L27/0002 ,  H04B3/145 ,  H04B3/23 ,  H04L5/023 ,  H04L25/03878

摘要： Digital subscriber modems (8, 15) for use in Asynchronous Digital Subscriber Line (ADSL) communications are disclosed. The central office modem (8) includes a digital transceiver function (10) and an analog front end function (12), where the analog front end function (12) is integrated into a single integrated circuit. According to the disclosed embodiments, the analog front end function (12) includes a transmit and a receive side. On the receive side, an impedance matching circuit (56) is coupled to the input of a programmable gain amplifier (54C). The impedance matching circuit (56) is controlled by the same control signals (C1, C2, C3) as used to select the gain of the programmable gain amplifier (54C), so that a constant input impedance is presented to the signal input (RXP), independent of the selected gain.

摘要翻译： 公开了用于异步数字用户线（ADSL）通信的数字用户调制解调器（8,15）。 中央办公室调制解调器（8）包括数字收发器功能（10）和模拟前端功能（12），其中模拟前端功能（12）被集成到单个集成电路中。 根据所公开的实施例，模拟前端功能（12）包括发送和接收侧。 在接收侧，阻抗匹配电路（56）耦合到可编程增益放大器（54C）的输入端。 阻抗匹配电路（56）由用于选择可编程增益放大器（54C）的增益的相同的控制信号（C1，C2，C3）来控制，使得恒定的输入阻抗被呈现给信号输入端 ），独立于所选增益。

公开(公告)号：US06535066B1

公开(公告)日：2003-03-18

申请号：US09886597

申请日：2001-06-21

申请人： David Petsko

发明人： David Petsko

IPC分类号： H03G310

CPC分类号： H03F1/0261 ,  H03F1/0205 ,  H03F1/32 ,  H03F3/24 ,  H03F2201/3203 ,  H03G3/3042

摘要： An adaptive bias control scheme for an Orthogonal Frequency Division Multiplex (“OFDM”) transmitter. The transmitter chain is comprised of class A amplifiers. The amplifiers in the transmit chain are backed off from P1dB to ensure linear amplification of the signal. Amplifier back off is defined as (Amplifier P1dB) minus (Average Signal Power). Since the efficiency of the amplifier decreases in direct proportion, to the back off, it is desirable to minimize back off while maintaining linearity. The back off is dependent on the peak to average power ratio (“PAPR”) of the OFDM waveform. The PAPR is measured on a symbol by symbol basis and the amplifier P1dB is adjusted in proportion to the PAPR of the symbol, maintaining a P1dB sufficient to provide the required back off dictated by the maximum PAPR of the OFDM waveform, but can be lowered for symbols with PAPR below the maximum. The average operating point of the amplifiers is reduced by the adaptive bias control on a symbol-by-symbol basis.

摘要翻译： 用于正交频分复用（“OFDM”）发射机的自适应偏置控制方案。 发射机链由A类放大器组成。 发射链中的放大器从P1dB退出，以确保信号的线性放大。 放大器退避定义为（放大器P1dB）减（平均信号功率）。 由于放大器的效率以直接比例降低，因此在保持线性的同时，希望最小化退避。 退避取决于OFDM波形的峰值与平均功率比（“PAPR”）。 PAPR是按符号进行测量的，并且放大器P1dB与符号的PAPR成比例地调整，保持足够的P1dB以提供由OFDM波形的最大PAPR所规定的所需的反向，但可以降低 符号PAPR低于最大值。 通过基于逐个符号的自适应偏置控制来减小放大器的平均工作点。

公开(公告)号：US06184752B2

公开(公告)日：2001-02-06

申请号：US09413393

申请日：1999-10-06

申请人： Pierre Dautriche

发明人： Pierre Dautriche

IPC分类号： H03G310

CPC分类号： H03G1/0088 ,  G11B7/005 ,  G11B7/0941

摘要： The device has reference current sources (T71, T72, T7M) which are arranged in such a way that the sum of the currents flowing through each of the said sources is equal to the input current (IIN, I′IN) and output current sources (T81, T82, T8N), in each of which the current flowing through the reference sources is duplicated and which are arranged in such a way that the sum of the currents flowing through the output sources is equal to the output current (IOUT, I′OUT). The number of reference sources (T71, T72, T7M) and output sources (T81, T82, T8N) which are connected is controlled by the digital signal (200) and determines the gain of the device. Application to the circuit for processing the signals output by a read head of an optical disc reader apparatus.

摘要翻译： 该装置具有参考电流源（T71，T72，T7M），其以流过每个所述源极的电流之和等于输入电流（IIN，I'IN）和输出电流源 （T81，T82，T8N），其中流过参考源的电流是复制的，并且以使得流过输出源的电流之和等于输出电流（IOUT，I 'OUT）。 所连接的参考源（T71，T72，T7M）和输出源（T81，T82，T8N）的数量由数字信号（200）控制，并确定器件的增益。 应用于电路，用于处理由光盘读取器装置的读取头输出的信号。

公开(公告)号：US06819180B2

公开(公告)日：2004-11-16

申请号：US10460492

申请日：2003-06-12

申请人： Enver Krvavac

发明人： Enver Krvavac

IPC分类号： H03G310

CPC分类号： H03F1/301 ,  H03F1/0266 ,  H03F3/193 ,  H03F2200/18 ,  H03F2200/451 ,  H03G3/3042

摘要： An adaptive bias control circuit for use with a radio frequency (RF) power amplifier, the RF power amplifier having an input (112) for receiving an input signal having a varying amplitude, an output (116), a first transistor (110), and a plurality of operating performance characteristics responsive to a quiescent operating point established by a bias current in the RF power amplifier, the bias control circuit having: a first circuit (120) coupled to the RF power amplifier for receiving a portion of the input signal; and a second transistor (122) for generating a rectified signal from the portion of the input signal, the rectified signal for causing the bias current to be controlled as a function of the amplitude of the input signal, the second transistor having a first and second terminal connected together and coupled to the first circuit and a third terminal coupled to a fixed voltage.

公开(公告)号：US06762647B1

公开(公告)日：2004-07-13

申请号：US10215802

申请日：2002-08-09

申请人： Thomas R. Apel

发明人： Thomas R. Apel

IPC分类号： H03G310

CPC分类号： H03F1/52 ,  H03G3/3042

摘要： A peak detector detects an amplifier output overvoltage condition if the amplifier drives a mismatched load impedance. In response to the detected overvoltage condition, a clamping transistor lowers a reference DC bias voltage supplied by a bias circuit to the amplifier. The lowered reference DC bias voltage lowers amplifier gain and output power, thus protecting the amplifier.