The invention provides an adjustable circuit device, comprising a first adjustment circuit, a second adjustment circuit, a
signal conditioner, an analog-to-
digital converter and a processor, wherein the processor receives the output
signal converted by the
signal conditioner and the analog-to-
digital converter and analyzes the
digital signal according to the pre-set rules; the
equivalent capacitance of the first adjustment circuit is adjusted by the transmission of the
control signal to control the opening and closing state of each switch in the first regulating circuit to realize the input or the
cut of the adjustable
capacitor according to the analysis result; and the fixed
capacitance is simulated into an adjustable
capacitance by controlling the gear connection state of the
multiplexer in the second adjustment circuit, changing the connected
voltage divider
resistor network tap position so as to adjust the
voltage across the
fixed capacitor. The device realizes the automatic adjustment of the partial
voltage capacitance through the
program control, can reduce the human input and greatly improves the working efficiency.