Design and Application of an Oscillator System Converts Temperature, Light, Force and Gamma Radiation to Time
S. M. El-Ghanam, H. A. Ashry, A. M. Swidan, F. A. S. Soliman and M. Morsi
The present paper is devoted on designing a three-phase symmetrical active-R oscillator circuit that can accurately converts different variables (temperature, light and force) into triangular waveform with excellent predictable time. The proposed oscillator circuit is based on using a quad operational amplifier in conjunction with the well-known non-linear resistances, namely: Temperature-Dependent Resistance (TDR), Light-Dependent Resistance (LDR), and Force-Dependent Resistance (FDR). The oscillation periods of the proposed oscillator system are shown to be 5.60 μsec, 3.53 μsec, and 2.15 μsec for room light intensity (200 lux), room temperature (27ºC), and a force value of 100 grams, respectively. On the other hand, a sensitivities value of 61.80 nsec/ºC, 10.60 nsec/lux, and 6.40 nsec/gm are obtained. Finally, in the field of radiation dosimetry, the proposed oscillator system shows an excellent application in gamma dose-and dose rate-measurements.
Keywords: Active-R oscillator, Temperature-Dependent Resistance (TDR), Light-Dependent Resistance (LDR), and Force-Dependent Resistance (FDR).