Abstract: The compact C-multiplier includes four MOSFETs operating in the subthreshold region using the translinear principle. The multiplier is controllable to meet designer requirements. A Tanner Tspice simulator is used to confirm the functionality of the design in 0.13 pm CMOS Technology. The circuit operates from a ±0.75 supply voltage. Simulation results indicate that the multiplication factor is large compared to existing designs.

Abstract: The compact CMOS current-mode analog multifunction circuit is based on an implementation using MOSFETs operating in a sub-threshold region and forming two overlapping translinear loops capable of performing multiplication, division, controllable gain current amplifier, current mode differential amplifier, and differential-input single-output current amplifier.

Abstract: The system for monitoring a liquid level in an underground storage tank provides an external visual indication of a liquid level, such as water level, within a sealed underground storage tank. The system includes an ultrasonic transducer for generating regularly pulsed ultrasonic signals and for receiving reflected ultrasonic signals, which are reflected from a surface of the liquid stored in the underground storage tank. A pulser connected to a timer is in communication with the ultrasonic transducer for generating regularly pulsed ultrasonic signals. The timer is further used to measure the time period between generation of one of the pulsed ultrasonic signals and reception of the corresponding reflected ultrasonic wave. The height between the ultrasonic transducer and the liquid surface is then calculated based upon the measured time period. The liquid level is then displayed to the user on an external display.