Design of operational amplifier, analog to digital converter for the measurement of bone strain using CMOS technology

Abstract

Measurement of bone strain is the key factor in the bone biology studies to understand the changes in the structure of bone mass. This will be helpful in the improvement of treatment process for the patients suffered due to bone diseases. The system for the design of bone strain requires the components which include sensors, amplifiers, analog to digital converters (ADC), filter and the processing unit. Whenever the bone is loaded, it creates a small adjustment in the bone mass. The measurement of bone strain system requires more accuracy because of this very minimum variation in the structure of bone mass. Strain gauge sensors are used to sense the change in interconnected plates of bone mass (strain). The strain is a minimum value and in the range of micros, it desires to be processed to get the original value of strain. The processing of the signal is easier if it is a digital signal when compared to analog signal. Hence the voltage signal from the sensor measuring the strain is transmitted. Then the transmitted signal is amplified through operational amplifier and the analog signal is converted to digital using the comparator circuit. These operational amplifier and comparator circuit are designed using Complementary Metal Oxide Semiconductor (CMOS) technology to reduce the power consumption and simulated with the help of Mentor graphics. The system takes long time to measure the strain so that the system power consumption should be low. Thus the analysis of strain is useful in the treatment of orthopedic diseases.