This research proposes a novel, more efficient bulk-driven current differential transconductance amplifier (BDCDTA) for low-voltage, low-power applications. The proposed design consists of a current difference unit followed by a transconductance amplifier, which utilizes a split transistor network approach to obtain high transconductance. In the biasing circuit, a current source and a split network are also incorporated, allowing the BDCDTA characteristics to be tuned as needed by properly selecting its value and the number of transistors. To demonstrate the capabilities of the proposed BDCDTA, a biquad filter is constructed. Furthermore, as a new BDCDTA application, frequency agile filters are also implemented. The frequency-agile filter, which has only three active elements, is simple to integrate, and the center frequency can easily be electronically adjusted by changing the bias current amount. The simulations are performed using PSPICE 180 nm CMOS technology parameters. All calculations and simulated outcomes validate the overall performance and potential of the presented circuit and its applications.