基于AD603程控增益大功率宽带直流放大器的设计

采用低噪声增益可程控集成运算放大器AD603和高频三极管2N2219和2N2905等器件设计了宽带直流放大器，该放大器具有增益可程控、功率高、频带宽、带宽可选择等特点。输入级采用两级AD603级联，以提高增益控制范围；中间级采用分立元件制作了高输出功率放大器，输出级设计了两路通频带分别为0～5MHz以及0～10MHz的低通滤波器实现带宽的可预置，通过51单片机可以对放大器增益和带宽进行控制。此外对提高直流放大器的各种性能指标提出了多种具体措施，在自动化要求较高的系统中具有很好的实用性。

Design based on AD603 programmable-gain high-power broadband DC amplifier

In this paper, a broadband DC amplifier was designed with an low-noise integrated programmable gain op-amp AD603 and high-frequency transistor 2N2219 and 2N2905 and other devices. The amplifier has features of programmable gain, high-frequency power, broad bandwidth, and selectable bandwidth. The input stage adapts two cascaded AD603 to increase gain controlling range~ middle-class composed of discrete components produces a high-output power amplifier. The output stage was designed to use low-pass filter with two bandwidth individually ranges from 0 to 5 MHz and from 0 to 10 MHz to achieve the preset of bandwidth, and both the gain of amplifier and the bandwidth can be controlled by the microcontroller 51. In addition, the context introduces a number of specific measures to improve the performance indicators of the DC amplifier. This amplifier has very good practicability in the system of higher automation.