We included a designing of low power tunable analog circuits built using independently driven FinFETs devices, where the controlling of the back gate provide the output on the front gate. We show that this could be an effective solution to conveniently tune the output of bulk CMOS analog circuits particularly for Schmitt trigger and operational transconductance amplifier circuits. FinFET devices can be used to increase the performance by reducing the leakage current and power dissipation, because front and back gates both are independently controlled. FinFET device has a higher controllability, resulting relatively high Ion/Ioff ratio. In this paper, we proposed a tunable analog circuit such as CMOS amplifier circuit, Schmitt trigger circuit, and operational transconductance amplifier circuit, these circuit blocks are necessary for low noise high performance ICs for analog applications. Gain, phase, group delay, and output response of analog tunable circuits have been discussed in this paper. The proposed FinFET based analog tunable circuits have been designed using Cadence Virtuoso tool at 45 nm.