Simulation of Voltage Controlled Tunable All Pass Filter Using LM13700 OTA

In recent years Operational Transconductance Amplifier based high frequency integrated circuits, filters and systems have been widely investigated. The usefulness of OTAs over conventional OP-Amps in the design of both first order and second order active filters are well documented. This paper discusses some of the tunability issues using the Matlab/Simulink® software which are previously unreported for any commercial OTA. Using the simulation results two first order voltage controlled all pass filters with phase tuning capability are proposed.

• Bhaba Priyo Das
• Neville Watson
• Yonghe Liu

• All pass filter
• Operational Transconductance Amplifier
• Simulation.

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