Design of High-Speed Current Comparator using SSF-Based CC-II

With shrinking feature size of MOSFET, the supply voltages and threshold voltages are scaled down very aggressively. This produces limitations in the performance of voltage mode comparators. This leads to increasing demand for current mode comparators in today’s scenario. The current mode comparators are successfully used in high-speed ADCs, oscillators, neural networks and ultra-high-speed communication for many signal processing applications. In this paper, a new topology of the second-generation current conveyor (CC-II) is proposed. The proposed design is based on a super source follower which uses a negative feedback configuration. Based on this design of CC-II, a new design of the current comparator is derived. The design is simulated in 0.13[Formula: see text][Formula: see text]m BSIM4 technology using [Formula: see text]0.6[Formula: see text]V power supply using the LTspice tool. The proposed CC-II offers a very low impedance at the X input terminal. Further, this new design of the current comparator performs very high-speed operation of around 0.073[Formula: see text]ns and an overall power dissipation of 5.84[Formula: see text]mW using an input current difference of [Formula: see text]15[Formula: see text]mA.