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公开(公告)号：US5451903A
公开(公告)日：1995-09-19
申请号：US264871
申请日：1994-06-24
申请人： Desmond R. Armstrong
发明人： Desmond R. Armstrong
摘要： An output driver (100) for driving an external impedance load (160) comprising an output stage (110) and an impedance element (120). An input signal to the output stage (110) is controlled to provide an output signal that then drives the external impedance load (160).The output stage (110) comprises an input controller (112) that couples to a current generator (114) and a current replicator (116). A voltage reference source (150) determines a quiescent output current level of the current generator (114). The impedance element (120) comprises a current modulating resistor (230) that couples a two polarity voltage supply (130) to the output stage (110).Operations of the output driver (100) depends on the external load impedance (160). For a high external impedance load, the output driver (100) functions as a simple voltage follower. For a low external impedance load, the output driver (100) functions as a single-ended push-pull circuit and provides a low distortion output signal under low voltage supply conditions.
摘要翻译： 一种用于驱动外部阻抗负载（160）的输出驱动器（100），包括输出级（110）和阻抗元件（120）。 控制到输出级（110）的输入信号，以提供输出信号，该输出信号然后驱动外部阻抗负载（160）。 输出级（110）包括耦合到电流发生器（114）和当前复制器（116）的输入控制器（112）。 电压参考源（150）确定电流发生器（114）的静态输出电流电平。 阻抗元件（120）包括将两极性电压源（130）耦合到输出级（110）的电流调制电阻（230）。 输出驱动器（100）的操作取决于外部负载阻抗（160）。 对于高外部阻抗负载，输出驱动器（100）用作简单的电压跟随器。 对于低外部阻抗负载，输出驱动器（100）用作单端推挽电路，并在低电压供电条件下提供低失真输出信号。
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2.发明授权Tachogenerator processing circuits and motor speed control systems including such circuits 失效TACHOGERERATOR加工电路和包括这种电路的电机速度控制系统
公开(公告)号：US4117384A
公开(公告)日：1978-09-26
申请号：US790700
申请日：1977-04-25
申请人： Desmond R. Armstrong
发明人： Desmond R. Armstrong
CPC分类号： H02P25/10 , H02P23/16 , Y10S388/915 , Y10S388/917
摘要： A circuit for processing the a.c. output of a tachogenerator whose frequency is proportional to the speed of a rotor of the tachogenerator, said circuit including voltage level detection means responsive to said a.c. output, key pulse producing means responsive to at least one output of the detection means to produce a key pulse whose duration is inversely proportional to the rotational speed, first gating means responsive to an output of the detection means and an output of the key pulse producing means to produce a reset pulse after a predetermined period in the interval between each key pulse, and a voltage generator responsive to each reset pulse to provide a predetermined output level and responsive to each key pulse to ramp that output level at a predetermined rate for the duration of that key pulse, whereby the output level of the voltage generator during each said predetermined period is a predetermined function of the rotational speed.
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公开(公告)号：US4920321A
公开(公告)日：1990-04-24
申请号：US289650
申请日：1988-12-22
申请人： Desmond R. Armstrong
发明人： Desmond R. Armstrong
CPC分类号： H03F1/302
摘要： An amplifier circuit wherein the output signal of an npn long-tailed transistor pair amplifier stage (1) is referenced to a first power supply point (5). In order to transfer this signal to the input of a second npn stage without using pnp transistors and without noise on the first supply point becoming superimposed on the signal, an intermediate stage (2) is provided. The intermediate stage comprises a current mirror (10) to the input and output of which are coupled the respective collectors of the pair transistors (3,4) via respective emitter followers (13,15) and respective resistors (14,16). The values of these resistors, the load resistors (6,7) of the pair transistors, and the current gains of the emitter followers and the current mirror are chosen such that any change in the potential on the output (17) of the intermediate stage (2) relative to a second power supply point (8), which would otherwise result from a change in the potential on the first supply point (5) relative to that on the second supply point, is compensated for by a change in the mirror output current, thus producing changes in the currents through two of the resistors (7,16).
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公开(公告)号：US4771223A
公开(公告)日：1988-09-13
申请号：US40910
申请日：1987-04-21
CPC分类号： H02P25/145 , H02P23/0077 , Y10S388/912
摘要： A speed control system for an a.c. electric motor (1) comprises a microcomputer (6) having an interrupt signal input (INT/TO) to which is coupled the outputs of a detector (10) for detecting zero-crossings of the a.c. supply voltage and a tachogenerator (11) driven by the motor. The microcomputer supplies firing pulses to a triac (2), connected in series with the motor, in response to an overflow of a clocked counter (CT). This counter is suitably preloaded at each zero-crossing. The counter is read each time a tachogenerator pulse occurs and the time which this reading indicates has elapsed since the immediately preceding zero-crossing is stored. A record is also kept in a register (ZCSLTA) of how many zero-crossings occur between each tachogenerator pulse and the next and from this, and the stored times relating to the relevant pulses, the period of the tachogenerator pulses and hence the actual speed of the motor is calculated. The preloading value for the counter is calculated from this and the required speed.
摘要翻译： 一种速度控制系统。 电动机（1）包括具有中断信号输入（INT / TO）的微计算机（6），耦合到检测器（10）的输出端，用于检测交流的过零点。 电源电压和由电机驱动的测速发电机（11）。 微计算机响应时钟计数器（CT）的溢出，向与电动机串联连接的三端双向可控硅开关元件（2）提供点火脉冲。 该计数器在每个过零点处适当预加载。 每当发生测速发电机脉冲并且从紧接在前的过零点开始经过该读取指示的时间之后，读取计数器。 记录也保存在一个登记册（ZCSLTA）中，每个测速发电机脉冲和下一个测速发生器脉冲之间发生多少过零点，以及与相关脉冲相关的存储时间，测速发电机脉冲的周期以及因此的实际速度 的电机计算。 计数器的预加载值由此和所需速度计算。
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5.发明授权Differential amplifier and current sensing circuit including such an amplifier 失效差分放大器和电流检测电路包括这样的放大器
公开(公告)号：US4885477A
公开(公告)日：1989-12-05
申请号：US203404
申请日：1988-06-06
CPC分类号： H03F3/45076
摘要： A differential amplifier includes first and second matched field-effect transistors (FETs) (21,22) having their source electrodes connected together and to a current source (2), and their drain electrodes connected respectively to an input and an output of a current mirror circuit (3). The FETs (21,22) are depletion-mode FETs, and the current source comprises parallel-connected third and fourth depletion-mode FETs (25,26) matched to the first and second FETs (21,22). The current source (2) and current mirror (3) act to constrain the first and second FETs (21,22), to operate over a predetermined operating curve, for which they are optimally matched to one another. The differential amplifier may be constructed as an integrated circuit, and may form part of a circuit for sensing current in a power semiconductor device.
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公开(公告)号：US4150303A
公开(公告)日：1979-04-17
申请号：US814282
申请日：1977-07-11
申请人： Desmond R. Armstrong
发明人： Desmond R. Armstrong
CPC分类号： D06F37/304 , Y02B40/52 , Y10T307/944 , Y10T307/951
摘要： A motor speed control circuit for use in a washing machine includes a timer which in normal operation accelerates the motor from a wash speed to a distribution speed before a fast acceleration to the spin dry speed. The control circuit includes speed measurement means for maintaining the motor at spin speed in the event of a power interruption during a spin cycle provided the drum speed remains above a given critical speed when the power returns. If not, a redistribution cycle takes place before the motor is accelerated to its spin speed.
摘要翻译： 用于洗衣机的电动机速度控制电路包括定时器，其在正常操作中，在快速加速到旋转干燥速度之前将电动机从洗涤速度加速到分配速度。 控制电路包括速度测量装置，用于在旋转循环期间电源中断的情况下将电动机保持在旋转速度，只要转速保持高于给定临界转速时的功率返回。 如果没有，则在马达加速到其旋转速度之前进行再分配循环。
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公开(公告)号：US5039878A
公开(公告)日：1991-08-13
申请号：US434759
申请日：1989-11-09
CPC分类号： G01K7/01 , G01K3/005 , Y10S323/907
摘要： In order to sense the temperature of an integrated circuit chip, a semiconductor junction device (D1) integrated on the chip is used to generate a first signal (V.sub.1) having a known variation with temperature. A second signal (V.sub.2) is generated by passing a PTAT current (I.sub.2) through a resistor (R1) so that the second signal (V.sub.2) has a known variation with temperature which is opposite in sign to that of the first signal (V.sub.1). The two signals are compared (42) to generate an output signal (OT) which is dependent on whether the temperature of the chip is below or above a predetermined threshold temperature. The current (I.sub.1) through the junction device (D1) is also PTAT, which provides a more accurate definition of the threshold temperature in terms of integrated circuit parameters.
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