Ultrasonic Distance Measurement Circuit based on ADuC7126 ARM7TDMI Processor

Application Circuit is a completely self-contained distance sensor that utilizes an ultrasonic transmitter and sensitive analog receiver in conjunction with a precision analog micro-controller to provide distance measurements. Unlike complicated PLL-based receivers, the sensor uses a sensitive window comparator circuit, thereby minimizing real estate and cost. The approximate range is from 50 cm to 10 m with a resolution of about 2 cm. Temperature compensation is provided by the integrated temperature sensor and ADC contained in the microcontroller. In industrial applications, distance measurement is a common requirement, such as fluid level sensing or sensing the distance between solids