1. Niš, November 4 th – 7 th, 2012 - 1 - M. Sc. Zivko Kokolanski Ph.D. Student kokolanski@feit.ukim.edu.mk

2. Niš, November 4 th – 7 th, 2012 - 2 - OUTLINE

3. Niš, November 4 th – 7 th, 2012 - 3 - SIGNAL CONDITIONING A/D SensorOscillator CC Programmable measurement system with A/D converter Programmable measurement system with oscillator Simple, low cost Direct digital interface Wider dynamic range Lower electromagnetic interference CC Relaxation oscillator C ref,R ref Sensor Direct Sensor-to-microcontroller interface ADVANTAGES: Programmable signal cond. circ. Sensor CC

4. Niš, November 4 th – 7 th, 2012 - 4 - MULTIVIBRATOR

5. Niš, November 4 th – 7 th, 2012 - 5 - MEASUREMENT UNCERTAINTY

6. Niš, November 4 th – 7 th, 2012 - 6 - MONOSTABLE MULTIVIBRATOR (555) FAMILY ???

7. Niš, November 4 th – 7 th, 2012 - 7 - MONOSTABLE MULTIVIBRATOR WITH SINGLE POINT CALIBRATION

8. Niš, November 4 th – 7 th, 2012 - 8 - SYSTEMATIC ERRORS Offset GainNonlinearity For  R x <1/2LSB The condition limits the measurement range

9. Niš, November 4 th – 7 th, 2012 - 9 - TRANSFER CHARACTERISTIC

10. Niš, November 4 th – 7 th, 2012 - 10 - TEMPERATURE VARIATION TEST Rapid temperature rise increased Tx and Tc for 2% Rx decreased 0.2% Single point calibration reduce the temperature effects nearly 10 times

11. Niš, November 4 th – 7 th, 2012 - 11 - CONCLUSIONS