Operational Amplifiers(运算放大器)A person working with an op-amp does not ordinarily need to be concerned with its internal construction. It is helpful ,however,to have some general understanding of what the internalcircuitry accomplishes. This permits the user to see how the device performs and indicates some of its limitations as a function unit.一个人与一个运算放大器工作并非通常需要与它的内部结构有关。
这是有帮助的，不过，有一些什么样的内部电路完成大致的了解。
这允许用户看到如何执行，并指出该设备作为一个功能单位，它的一些局限性。
The internal circuitry of an op-amp can be divided into three functional units, Figure 8.4 shows a simplified diagram of the internal functional or an op-amp .Notice that each function is enclosed in a triangle .Electronic schematics use the triangel to denote the amplification function, This diagram shows that the op-amp has three basic amplification functions. These functions are general called stages of amplification. A stage of amplification contains one or more active devices and all the associated components needed to achieve amplification .一个运算放大器的内部电路可以分为三个功能单元，图8.4显示了一个简化的内部功能图或一个运算放大器。
