4-bit 8-segment digital tube drive circuit

Shown is the display driving circuit of a digital voltmeter . Liquid crystal display devices (LCDs) do not emit light themselves. They use external
incident light to display numbers. IC】LD130 is a voltage input detection circuit, which converts the detected analog voltage value into a 4-bit digital signal,
which is sent to the digital display driver integrated circuit JC2 DF411 through the ◎~@ pins. IC 2 outputs three sets of 7-segment driving signals. The +^ symbol before the number
is driven by two gate circuits in CD4030.