基于PIC16C72的水位水温控制器的设计

为满足落水式太阳能热水器自动控制的要求,设计了一个基于PIC16C72单片机的水温水位控制器。以NTC热敏电阻作为测温传感器,用PIC16C72内置的多路8位A/D转换器把NTC热敏电阻上的压降转换为数字量实现测温。通过非对称多谐振荡器电路把水位传感器的等效电阻转换为振荡信号的频率,然后用PIC16C72内置的计数器测量频率的高低,实现对水位的测量。介绍了控制器的工作原理、完整的硬件电路和功能。该设计省去了温度测量信号调理电路、专用A/D转换和输出译码驱动芯片,具有硬件系统组成简单、可靠性好的特点。

Design of water level and temperature controller based on PIC16C72

To satisfy the control demand of solar water heater,a controller of water temperature and water level was designed based on PIC16C72.With NTC thermistor as temperature sensor,water temperature and water tube temperature were measured by a multi-channel 8-bit A/D convertor embedded in PIC16C72.An unsymmetrical oscillator was utilized to convert the equivalent resistance of the water level sensor to oscillating frequency which was measured by a counter embedded in PIC16C72.In this paper,the work principle,hardware circuit and function of the controller were given.It only utilized single microchip directly to realize the function of measuring and control.The circuit is very simple in structure and it can satisfy the accuracy of measuring temperature,so it can not only decrease the cost of the entire system,but also increase the reliability of the system.