一种高性能机车速度数模转换装置的设计

The design of a high-performance locomotive speed digital-to-analog converter

为了适应铁路机车运行高性能、高可靠性要求,设计了一种高性能的机车速度数模转换装置.其作用是将机车轮对上的DF16型光电速度传感器传输来的数字脉冲信号,转换成0～6 V,0～20 mA两种模拟信号.该装置仅用2块IC芯片LM331和AD694及少量外围电路.其中LM331是将输入的数字脉冲信号转换成一定幅值的电压信号,然后由AD694将输出的电压信号转换成标准0～20 mA电流和0～6 V电压两种信号输出.该装置具有转换速度快、精度高（0.1％）、温度漂移小（100 ppm/℃）性能可靠等优点,是一款高性能的数模转换装置.

In order to adapt to the railway locomotive running high-performance, high-reliability requirements, the article describes a high-performance locomotive speed digital to analog conversion, Its role is to be stalled on the wheels of the DFl6-type photoelectric speed sensor digital pulse signal, converted into 0~6V ,0-20 mA two kinds of analog signals. The device only two IC chip LM331 and AD694 and a small amount of peripheral circuits. Wherein the LM331 is a digital input pulse signal is converted into a voltage signal of a certain amplitude, the output will then be provided by the AD694 voltage signal is converted into a standard 0~20mA current and voltage of 0~6V two signal outputs. The device has the advantages of fast conversion speed and high accuracy as 0.1%, small temperature drift as 100ppm/℃ and reliable performance, is a high-precision digital-to-analog conversion device.