Realization of Electronically Controllable Current-mode Square-rooting Circuit Based on MO-CFTA

This article proposes a current-mode square-rooting circuit using current follower transconductance amplifier (CTFA). The amplitude of the output current can be electronically controlled via input bias current with wide input dynamic range. The proposed circuit consists of only single CFTA. Without any matching conditions and external passive elements, the circuit is then appropriate for an IC architecture. The magnitude of the output signal is temperature-insensitive. The PSpice simulation results are depicted, and the given results agree well with the theoretical anticipation. The power consumption is approximately 1.96mW at ±1.5V supply voltages.

Authors:

• P. Silapan
• C. Chanapromma
• T. Worachak

Keywords:

• CFTA
• Current-mode
• Square-rooting Circuit

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