Voltage-current converter
    1.
    发明授权
    Voltage-current converter 失效
    电压电流转换器

    公开(公告)号:US4682098A

    公开(公告)日:1987-07-21

    申请号:US880854

    申请日:1986-07-01

    CPC分类号: H03F1/3211

    摘要: A voltage-current converter includes a first current-source (I.sub.1) coupled by means of a diode-arranged first transistor (T.sub.1) to a first terminal (1) at reference potential and by means of a diode-arranged second transistor (T.sub.2) to a second terminal (2). The bases of a third (T.sub.3) and a fourth (T.sub.4) transistor are coupled to the first (1) and the second (2) terminal, respectively. The emitters of these transistors (T.sub.3,T.sub.4) are coupled to a second current source (I.sub.2). A voltage source (V) and a resistor (R.sub.1) for converting the voltage (V) into a signal current are arranged between the first (1) and the second (2) terminal. The signal current is amplified by the translinear-circuit of the first, second, third and fourth transistors (T.sub.1 -T.sub.4) and fed to the outputs (30,40) via cascode transistors (T.sub.9,T.sub.10). To correct the non-linearity in the voltage-current conversion due to the non-linear emitter resistors of the first (T.sub.1) and the second (T.sub.2) transistor, a correction circuit (5) having a negative input resistance is coupled to the first (1) and the second (2) terminal.

    摘要翻译: 电压 - 电流转换器包括通过二极管布置的第一晶体管(T1)与参考电位的第一端子(1)耦合的第一电流源(I1),并且借助于二极管布置的第二晶体管(T2) 到第二端子(2)。 第三(T3)和第四(T4)晶体管的基极分别耦合到第一(1)和第二(2)端子。 这些晶体管(T3,T4)的发射极耦合到第二电流源(I2)。 在第一(1)和第二(2)端子之间布置有用于将电压(V)转换成信号电流的电压源(V)和电阻器(R1)。 信号电流由第一,第二,第三和第四晶体管(T1-T4)的跨导线路放大,并通过共源共栅晶体管(T9,T10)馈送到输出端(30,40)。 为了校正由于第一(T1)和第二(T2)晶体管的非线性发射极电阻引起的电压 - 电流转换中的非线性,具有负输入电阻的校正电路(5)耦合到第一 (1)和第二(2)端子。

    Amplifier arrangement
    2.
    发明授权
    Amplifier arrangement 失效
    放大器布置

    公开(公告)号:US4628280A

    公开(公告)日:1986-12-09

    申请号:US764142

    申请日:1985-08-09

    摘要: An amplifier that supplies a bias current (I.sub.t) which is dependent on an input signal (V.sub.i) to a junction point (2) of the source electrodes of first and second transistors (T.sub.1, T.sub.2). The amplifier comprises a control circuit that limits the bias current so it cannot increase more than is necessary to obtain a high slew rate, thereby minimizing dissipation by the amplifier. This control circuit comprises a third and a fourth transistor (T.sub.3, T.sub.4) arranged in parallel with the first transistor (T.sub.1) and the second transistor (T.sub.2), respectively, and which carry currents (I.sub.3, I.sub.4) which are proportional to the currents (I.sub.1, I.sub.2) in the first and the second transistor. A selection circuit (5) applies the smaller of the two currents (I.sub.3, I.sub.4) in the third and the fourth transistor to an output (8) where this current is compared with a reference current (I.sub.o) from a current source (9). The difference between these currents is applied to a current amplifier ( 10), which supplies an increasing bias current (I.sub.t) until the smaller of the two currents (I.sub.3, I.sub.4) in the third and the fourth transistor equals the reference current.

    摘要翻译: 向第一和第二晶体管(T1,T2)的源电极的接合点(2)提供取决于输入信号(Vi)的偏置电流(It)的放大器。 放大器包括限制偏置电流的控制电路,因此不能增加获得高压摆率所必需的电流,从而使放大器的耗散最小化。 该控制电路包括分别与第一晶体管(T1)和第二晶体管(T2)并联布置的第三和第四晶体管(T3,T4),并且它们与电流成比例的载流电流(I3,I4) (I1,I2)在第一和第二晶体管中。 选择电路(5)将第三和第四晶体管中的两个电流(I3,I4)中的较小的一个电路与来自电流源(9)的参考电流(Io)进行比较的输出(8) 。 这些电流之间的差异被施加到电流放大器(10),其提供增加的偏置电流(It),直到第三和第四晶体管中的两个电流(I3,I4)中的较小的一个等于参考电流。

    Differential amplifier having rail-to-rail input capability and
square-root current control
    3.
    发明授权
    Differential amplifier having rail-to-rail input capability and square-root current control 失效
    具有轨到轨输入能力和平方根电流控制的差分放大器

    公开(公告)号:US5371474A

    公开(公告)日:1994-12-06

    申请号:US197656

    申请日:1994-02-17

    IPC分类号: H03F3/45

    摘要: A differential amplifier contains a pair of differential portions (10 and 12) that together provide representative signal amplification across the full amplifier power-supply voltage range. Each differential portion normally contains a pair of like-polarity differentially coupled FETs (Q1 and Q2, Q3 and Q4) that divide a tail current (I.sub.N, I.sub.P) into a pair of main currents (I.sub.1 and I.sub.2, I.sub.3 and I.sub.4). The two FET pairs are complementary. A square-root circuit (24) controls the tail currents in such a way that the sum of their square roots is largely constant. Consequently, the amplifier transconductance is largely constant.

    摘要翻译: 差分放大器包含一对在整个放大器电源电压范围内提供代表性信号放大的差分部分(10和12)。 每个差分部分通常包含一对将尾电流(IN,IP)分成一对主电流(I1和I2,I3和I4)的类似极性的差分耦合FET(Q1和Q2,Q3和Q4)。 两个FET对是互补的。 平方根电路(24)以这样的方式控制尾电流,使得它们的平方根的总和大部分恒定。 因此,放大器跨导在很大程度上是恒定的。