Therefore, when selecting an optoco

Therefore, when selecting an optocoupler, the designer must make sure the rise and fall times
are fast enough for the required signaling rate.
The current transfer ratio (CTR) is the ratio of output current to input current and relates to the
drive capabilities and logic thresholds of the circuit. The optocoupler must be efficient enough to
switch to valid logic levels under all conditions. Typical values of CTR range from 75% to 300%.
The pullup resistors (R2, R3, and R5) limit the current through the LED. A value of R2 that is too
large does not allow enough current for reliable switching. A value too low saturates the output
stage of the driving logic stage. A value of 330 Ω for R2 allows an LED current of approximately
10 mA, which is appropriate for most optocouplers.
The phototransistor biasing resistors (R1, R4, and R6) set the voltage levels for the isolated
logic outputs. For a typical optocoupler with CTR greater than 50% and LED current of 10 mA, a
value of 5.1 kΩ has abundant margin for switching logic levels.
Another implementation of the isolated interface is shown in Figure 3. In this Illustration,
optocouplers are used to transmit the digital signals across the isolation barrier. Optocouplers
are commonly used in applications where the superior performance of digital isolators is not
needed.

結果 (中文) 1:

因此，当选择光电耦合器，设计器必须确保上升和下降时间是为所需的信号速率不够快。电流传输比 (CTR) 是输出电流与输入电流的比值，涉及驱动器功能和电路的逻辑阈值。光耦必须足够有效的切换到在所有条件下有效的逻辑电平。点击率范围从 75%到 300%的典型值。上拉电阻 （R2、 R3 和 R5） 限制通过 LED 电流。R2 也是一个值大不可靠切换允许足够的电流。一个值太低饱和输出驾驶的逻辑阶段的阶段。R2 为 330 Ω 值允许的 LED 电流约10 马，是适合大多数光电耦合器。光敏三极管偏置电阻 （R1、 R4 和 R6） 设置为隔离电压等级逻辑的产出。典型的光电耦合器与点击率大于 50%和 LED 电流的 10 马，5.1 k ω 值有裕丰切换逻辑电平。另一个实施例的孤立的界面如图 3 所示。在此图中，光电耦合器用于通过隔离屏障传输的数字信号。光电耦合器常用的应用程序性能优越的数字隔离器在哪里不需要。

結果 (中文) 3:

因此，当选择一个光耦，设计者必须确保的上升和下降时间对所需的信号速率足够快。电流传输比（CTR）是输出电流对输入电流的比值和涉及的电路的驱动能力和逻辑阈值。光耦必须有效在所有条件下切换到有效的逻辑电平。CTR的范围从75%到300%的典型值。上拉电阻（R2，R3和R5，限制流过LED的电流）。R2的值太大不允许有足够的电流进行可靠的开关。值太低饱和输出驱动逻辑阶段。一个价值330ΩR2允许LED电流约10毫安，这是适合大多数光电耦合器。三极管的偏置电阻（R1、R4和R6，）孤立的设定电压水平逻辑输出。一个典型的点击率大于50%和LED电流10毫安光耦，一5.1 K值有Ω切换逻辑层次丰富的边缘。隔离接口的另一个实现如图3所示。在这个例子中，光电耦合器是用来跨越隔离屏障传输数字信号。光耦元件通常在应用程序中使用了数字隔离器的优越性能，不需要.