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1.发明授权Programmable voltage-controlled oscillator having control current generating and compensating circuits 失效具有控制电流产生和补偿电路的可编程压控振荡器
公开(公告)号：US5399994A
公开(公告)日：1995-03-21
申请号：US129713
申请日：1993-09-30
CPC分类号： H03K3/03 , Y10S331/03
摘要： A programmable VCO circuit (300, 700) and method of use are provided whereby a current proportional to the strength of the NMOS process used to fabricate the circuit may be subtracted from the control current derived at the circuit's input, to compensate for process variations. Also, a programmable VCO circuit (300) and method of use are provided whereby a current developed from one-half the supply voltage for the VCO circuit may be subtracted from the control current derived at the circuit's input, in order to cause programmed gain changes to occur about the center of the control voltage range, and minimize output "jitter" when the VCO is used in a phase-locked loop. A gain compensation circuit (800) is also provided to linearize the gain of the programmable VCO circuit (300) for higher control voltage levels and thereby extend the VCO's effective operating range.
摘要翻译： 提供了一种可编程VCO电路（300,700）和使用方法，其中可以从在电路输入端导出的控制电流中减去与用于制造电路的NMOS工艺的强度成比例的电流，以补偿工艺变化。 此外，提供了一种可编程VCO电路（300）和使用方法，由此可以从在电路输入端导出的控制电流中减去用于VCO电路的电源电压的一半产生的电流，以便产生编程的增益变化 发生在控制电压范围的中心，并且当VCO用于锁相环时，输出“抖动”最小化。 还提供增益补偿电路（800）以使可编程VCO电路（300）的增益线性化，以实现更高的控制电压电平，从而扩展VCO的有效工作范围。
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2.发明授权Apparatus and method for accurately establishing a cut-off frequency in an electronic filter 失效在电子滤波器中精确建立截止频率的装置和方法
公开(公告)号：US5650950A
公开(公告)日：1997-07-22
申请号：US455867
申请日：1995-05-31
CPC分类号： H03H17/0294
摘要： A programmable, electronic filter (10) includes a memory device such as a Read Only Memory ROM (22) for storing specific cut-off frequency adjustment data corresponding to various cut-off frequencies. The ROM (22) receives a ROM address (28) corresponding to a cut-off frequency signal (26). The ROM (22) generates a specific cut-off frequency adjustment value (30) for a digital-to-analog convertor (20) to produce an output reference current (34). A reference voltage (40), an error amplifier (14), a master transconductance element (16), and a capacitor (18) serve as a tuning loop and ultimately produce a control signal (38) in response to the output reference current (34). Control signal (38) serves as an input to slave filter (12) along with the cut-off frequency signal (26). The slave filter (12) may then serve as an electronic filter having the desired frequency-response characteristic. The slave filter (12) may then receive a slave filter input signal (44) and provide a filtered output signal (46) having an accurate frequency-response characteristic at the desired cut-off frequency.
摘要翻译： 可编程电子滤波器（10）包括诸如只读存储器ROM（22）的存储器件，用于存储对应于各种截止频率的特定截止频率调节数据。 ROM（22）接收对应于截止频率信号（26）的ROM地址（28）。 ROM（22）产生用于数模转换器（20）的特定截止频率调整值（30）以产生输出参考电流（34）。 参考电压（40），误差放大器（14），主跨导元件（16）和电容器（18）用作调谐回路，并且响应于输出参考电流（38）最终产生控制信号（38） 34）。 控制信号（38）与截止频率信号（26）一起用作从滤波器（12）的输入。 然后，从滤波器（12）可以用作具有期望的频率响应特性的电子滤波器。 然后，从滤波器（12）可接收从滤波器输入信号（44），并提供具有所需截止频率的精确频率响应特性的滤波输出信号（46）。
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公开(公告)号：US5528179A
公开(公告)日：1996-06-18
申请号：US455815
申请日：1995-05-31
CPC分类号： H03G1/0023 , H03H11/0433 , H03H11/0472
摘要： A constant capacitance programmable transconductance input stage (36) includes a first transconductance device (50), second transconductance device (52), and first switch (44) for providing a programmable input stage with a constant input capacitance. The first transconductance device (50) has two inputs and the second transconductance device (52) has two inputs. A first positive input (22) couples directly to one input of the first transconductance device (50) while a first negative input (23) couples directly to one input of the second transconductance device (52). The first positive input (22) and the first negative input (23) are switchably coupled to the remaining inputs of first transconductance device (50) and second transconductance device (52). Depending on the configuration of the first switch (44), either both transconductance devices contribute to the overall transconductance of constant capacitance programmable transconductance input stage (36) or neither does. In either event, the input capacitance remains constant.
摘要翻译： 恒定电容可编程跨导输入级（36）包括第一跨导器件（50），第二跨导器件（52）和用于向可编程输入级提供恒定输入电容的第一开关（44）。 第一跨导器件（50）具有两个输入端，第二跨导器件（52）具有两个输入端。 第一正输入端（22）直接耦合到第一跨导器件（50）的一个输入端，而第一负输入端（23）直接耦合到第二跨导器件（52）的一个输入端。 第一正输入（22）和第一负输入（23）可切换地耦合到第一跨导器件（50）和第二跨导器件（52）的剩余输入。 根据第一开关（44）的配置，两个跨导器件都有助于恒定电容可编程跨导输入级（36）的整体跨导，或者也不参与。 在任一情况下，输入电容保持恒定。
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4.发明授权Circuit and method for programmably changing the transconductance of a transconductor circuit 失效用于可编程地改变跨导电路的跨导的电路和方法
公开(公告)号：US5994926A
公开(公告)日：1999-11-30
申请号：US838300
申请日：1997-04-16
CPC分类号： H03G1/0023 , H03F3/45076
摘要： A programmably variable transconductance circuit (10) and method for varying its transconductance includes first and second current control input devices (16, 18), each having an input (17,19) to which a differential input voltage may be applied. A pair of current steering circuits (26, 28, 30, 32) are each connected in series with a respective one of the first and second current control devices (16, 18) for dividing respective currents in the first and second current control devices (16, 18) between a differential output current path (12, 14) and another current flow path, and a programmable voltage source (90) supplying V.sub.CONTROL is connected to control the current division by the current steering circuits (26, 28, 30, 32). The programmable voltage, V.sub.CONTROL, is provided by a programmable current control loop (90), which incorporates a master transconductance circuit, to establish a constant transconductance independently of temperature variations. A dynamically controllable resistance, such as an MOS transistor (24), or the like, is connected between the first and second current control input devices (16, 18), and a second voltage source (V.sub.GATE) is connected to the dynamically controllable resistance (24) to maintain the dynamically controllable resistance (24) at a constant value.
摘要翻译： 用于改变其跨导的可编程可变跨导电路（10）和方法包括第一和第二电流控制输入装置（16,18），每个具有可以施加差动输入电压的输入端（17,19）。 一对电流转向电路（26,28,30,32）各自与第一和第二电流控制装置（16,18）中的相应一个串联连接，用于分开第一和第二电流控制装置（ 16,28,30,30,40,30,40,30,40,30,40,30,40,30,40,30,40,40,30,40,30,40,40,40,40,43,40,40,40,40,40,40,40,40,40,40,40,40,40,62,62,62,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64 32）。 可编程电压VCONTROL由可编程电流控制回路（90）提供，可编程电流控制回路（90）包含主跨导电路，以独立于温度变化建立恒定跨导。 诸如MOS晶体管（24）等的动态可控电阻连接在第一和第二电流控制输入装置（16,18）之间，第二电压源（VGATE）连接到动态可控电阻 （24）以将所述动态可控电阻（24）保持在恒定值。
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5.发明申请公开(公告)号：US20120044020A1
公开(公告)日：2012-02-23
申请号：US12861621
申请日：2010-08-23
IPC分类号： H03F3/217
CPC分类号： H03F3/2173
摘要： Recently, there has been an increased desire to measure load currents of class-D amplifiers to improve performance. The traditional solution has been to include one or more discrete components in series with the load, but this degrades performance. Here, however, circuit is provided (which includes sample-and-hold circuit) that accurately measures load currents without inhibiting performance and that is not inhibited by the phase differences between the load voltage and load current.
摘要翻译： 近来，已经越来越希望测量D类放大器的负载电流以提高性能。 传统的解决方案是将一个或多个独立组件与负载串联，但这会降低性能。 然而，这里提供了电路（其包括采样和保持电路），其精确地测量负载电流而不抑制性能，并且不受负载电压和负载电流之间的相位差的阻碍。
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公开(公告)号：US07323793B2
公开(公告)日：2008-01-29
申请号：US10740998
申请日：2003-12-19
CPC分类号： H03F3/21 , H03F1/02 , H03F1/34 , H03F1/56 , Y10T307/422
摘要： A system and method for driving a load at a desired operating level. A driver is connected to a load. The load can be selected from a plurality of loads by a selection system, such as a multiplexer, or a single load can be utilized. Feedback from the load is provided to the driver for achieving the desired operating level. A zero temperature coefficient resistance formed by two resistors having different resistances can be used so that the driver emulates an ideal resistor having a substantially zero temperature coefficient, providing a temperature independent current to the load.
摘要翻译： 一种用于以期望的操作水平驱动负载的系统和方法。 驱动器连接到负载。 可以通过诸如多路复用器之类的选择系统从多个负载中选择负载，或者可以使用单个负载。 来自负载的反馈被提供给驾驶员以实现期望的操作水平。 可以使用由具有不同电阻的两个电阻器形成的零温度系数电阻，使得驱动器模拟具有基本为零的温度系数的理想电阻器，为负载提供与温度无关的电流。
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公开(公告)号：US07061332B2
公开(公告)日：2006-06-13
申请号：US10954932
申请日：2004-09-30
CPC分类号： H03L7/0891 , H03L7/10
摘要： A control voltage window generator that tracks process, voltage supply, and temperature variations for a voltage controlled oscillator includes: a first transistor of a first conductivity type coupled between a supply voltage node and an upper control voltage node; and a second transistor of a second conductivity type coupled to the upper control voltage node to compensate for process variations in devices of the first conductivity type. Additionally, a target pull-in voltage generator includes circuitry for providing a pull-in control voltage that will always be inside the control voltage window, and also tracks process, voltage supply, and temperature variations.
摘要翻译： 跟踪压控振荡器的过程，电压供应和温度变化的控制电压窗口发生器包括：耦合在电源电压节点和上部控制电压节点之间的第一导电类型的第一晶体管; 以及耦合到上部控制电压节点的第二导电类型的第二晶体管，以补偿第一导电类型的器件中的工艺变化。 此外，目标引入电压发生器包括用于提供总是在控制电压窗口内部的引入控制电压的电路，并且还跟踪过程，电压供应和温度变化。
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公开(公告)号：US06985045B2
公开(公告)日：2006-01-10
申请号：US10791937
申请日：2004-03-02
IPC分类号： H03L5/00
摘要： A gain controlled voltage controlled oscillator. A current controlled oscillator is adapted to provide an output signal oscillating at a frequency controllable by controlling a current applied thereto. A first current source provides a first control current controllable by controlling a voltage applied thereto that has a predetermined range. A first current mirror is adapted to mirror the control current to the current controlled oscillator. A second current source is adapted to provide a second control current for mirroring to the current controlled oscillator by the first current mirror when the control voltage is in a low portion of the range.
摘要翻译： 增益控制压控振荡器。 电流控制振荡器适于提供以通过控制施加到其上的电流可控的频率振荡的输出信号。 第一电流源通过控制施加到其上的具有预定范围的电压来提供可控制的第一控制电流。 第一电流镜适于将控制电流镜像到当前受控振荡器。 当控制电压处于该范围的低部分时，第二电流源适于提供用于通过第一电流镜将电流控制振荡器镜像的第二控制电流。
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公开(公告)号：US06927719B1
公开(公告)日：2005-08-09
申请号：US10794864
申请日：2004-03-04
CPC分类号： H03M1/0604 , H03M1/687 , H03M1/745 , H03M1/747
摘要： A segmented current mode DAC (200) is disclosed herein having a current matching circuit (260) that compensates for the current mismatch produced by the transistors of each current source. This segmented current mode DAC (200) includes an input stage (210), a first and second controllable current source (270, 220), a current matching circuit (260), and an output switching network (272–274, 222–236). The first controllable current source (270) couples to receive a mirrored current as provided by the input stage (210) to provide a current source output controllable in current increments responsive to the M least significant bits for converting of the digital signal to analog form, where M is less than N. The second controllable current source (220) couples to receive the mirrored current to provide a current source output controllable in current increments responsive to the N−M most significant bits for converting of the digital signal to analog form. The current matching circuit (260) couple between the first and second controllable current sources (270,220) to match the current of the first controllable current source (270) and the second controllable current source (220). Specifically, the current matching circuit (260) connects between each sub-DAC (270,220) to force the drain-to-source voltage of a transistor (252) representing the first bit of the MSB binary weighted sub-DAC (220) to be the same as the drain-to-source voltage of the transistor (278) representing the LSB thermometer decoded sub-DAC (270).
摘要翻译： 本文公开了分段电流模式DAC（200），其具有补偿由每个电流源的晶体管产生的电流失配的电流匹配电路（260）。 该分段电流模式DAC（200）包括输入级（210），第一和第二可控电流源（270,220），电流匹配电路（260）和输出交换网络（272-274,222-236 ）。 第一可控电流源（270）耦合以接收由输入级（210）提供的镜像电流，以响应于用于将数字信号转换为模拟形式的M个最低有效位来提供以当前增量可控的电流源输出， 其中M小于N.第二可控电流源（220）耦合以接收镜像电流，以响应于用于将数字信号转换为模拟形式的NM最高有效位来提供以当前增量可控的电流源输出。 电流匹配电路（260）耦合在第一和第二可控电流源（270,220）之间，以匹配第一可控电流源（270）和第二可控电流源（220）的电流。 具体地，电流匹配电路260连接在每个子DAC（270,220）之间，以将表示MSB二进制加权子DAC（220）的第一位的晶体管（252）的漏 - 源电压强制为 与表示LSB温度计解码子DAC（270）的晶体管（278）的漏极 - 源极电压相同。
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公开(公告)号：US6011418A
公开(公告)日：2000-01-04
申请号：US988545
申请日：1997-12-10
CPC分类号： H03H11/0422 , G11B5/012 , G11B5/09
摘要： A hard disk drive system (10) has a read/write head (12) coupled to a read channel circuit (23) in an integrated circuit (13). The read channel circuit includes a bipolar transconductance-C filter (26) having at least one capacitor (27) with a capacitance value that may vary from an intended value. A temperature compensating voltage (VPTAT) is converted to a first current, a programming circuit (51) produces a second current (IPROG) as a function of the first current and a digital compensating input (54), and the second current is converted to a voltage (61) and used to control characteristics of the filter circuit. A trimming circuit (46) shunts away from the programming circuit a portion of the current generated by the voltage-to-current converter circuit, which portion is defined by a digital trim input (48).
摘要翻译： 硬盘驱动器系统（10）具有耦合到集成电路（13）中的读通道电路（23）的读/写头（12）。 读通道电路包括具有至少一个电容器（27）的双极跨导C滤波器（26），电容值可以从预期值变化。 温度补偿电压（VPTAT）被转换为第一电流，编程电路（51）产生作为第一电流和数字补偿输入（54）的函数的第二电流（IPROG），并且第二电流被转换为 电压（61），用于控制滤波电路的特性。 微调电路（46）将由电压 - 电流转换器电路产生的电流的一部分与编程电路分开，该部分由数字微调输入（48）限定。
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