Minimum Component Based Sinusoidal Oscillator Using Single OTRA

In this paper a new Operational transresistance amplifier (OTRA) based sinusoidal oscillator is proposed. It uses two resistors, two capacitors and a single OTRA. Sensitivity analysis and non-ideality analysis behavior of OTRA on oscillator operation is also investigated. The proposed oscillator circuit is designed using PSPICE simulation and 0.18µm AGILENT CMOS process parameters. PSPICE simulation results agree well with the theoretical analysis of the proposed circuit

New Electronic Interface Circuits for Humidity Measurement Based on the Current Processing Technique

The paper describes a new electronic conditioning circuit based on the current-processing technique for accurate and reliable humidity measurement, without post-processing requirements. Pseudobrookite nanocrystalline (Fe2TiO5) thick film was used as capacitive humidity transducer in the proposed design. The interface integrated circuit was realized in TSMC 0.18 mu m CMOS technology, but commercial devices were used for practical realization. The sensing principle of the sensor was obtained by converting the information on environment humidity into a frequency variable square-wave electric current signal. The proposed solution features high linearity, insensitivity to temperature, as well as low power consumption. The sensor has a linear function with relative humidity in the range of Relative Humidity (RH) 30-90 %, error below 1.5 %, and sensitivity 8.3 x 10(14) Hz/F evaluated over the full range of changes. A fast recovery without the need of any refreshing methods was observed with a change in RH. The total power dissipation of readout circuitry was 1 mW