Programmable Floating Gate Transistor Operating as a Resistor for Analog Applications

This paper presents a programmable resistor using two-input floating gate MOS transistor (FGMOST). One of the two-input gates is connected to the drain and the other is connected to a tuned voltage to control the floating gate transistor resistance. A wide range of the programmable resistance is achieved by controlling the tuned voltage. The resistance is changed by 33% by varying the tuned voltage by 0.4 V. Three applications based on FGMOST operated as a resistor are proposed. These are tunable filter, tunable triangular oscillator and tunable amplifier. The cut-off frequency of the low-pass filter is tuned from 21.4 kHz to 32.1 kHz by controlling the tuned voltage by 0.4 V. The oscillation frequency of the triangular oscillator is varied from 336.18 kHz to 540.2 kHz by varying the tuned voltage by 0.4. Also, the gain of the amplifier is changed by 50% by changing the tuned voltage by 0.4 V.