Abstract
The paper proposes the use of switches to synthesize immittance logic elements, which makes it possible to ensure the operation of logic elements at various fixed operating frequencies. This in turn allows to increase the operating frequency range of such elements. For the first time, a mathematical model of a multi-frequency immittance logic R-element "NOT" was developed. It allowed to determine the transient characteristics at different operating frequencies. The circuit of the multi-frequency opto-immittance logic R-element "NOT" was developed. The results of the study of its transient characteristics showed the possibility of using the circuit in the design of passive immittance logic elements with an extended operating frequency range.