Novel electronically controlled current-mode Schmitt trigger based on single active element

In this paper, a simple circuit of current-mode Schmitt trigger consists of only single dual-X current conveyor transconductance amplifier (DXCCTA) is proposed. The proposed Schmitt trigger does not need any passive component for its realization. Its threshold levels and output current amplitude are electronically and independently adjustable with the help of corresponding input bias currents. The proposed circuit also has the features of good operational frequency range, ease of cascadability and low power consumption. The effects of non-idealities of DXCCTA and the effects of MOS transistors mismatch on the proposed Schmitt trigger are investigated. Moreover, the output current amplitude is less affected by temperature variation. HSPICE simulation results are shown to verify the performance of the proposed Schmitt trigger.