CD45 1 1: Dual-in-line 16-pin subpackage, which converts BCD standard code into signals needed to drive seven-segment digital tubes. Among them, A~D four lines are BCD code input. Active high. A is the low input and d is the high input. A~g seven-stage output high level drives cathode digital tube to emit light. LE is the latch control terminal, and the input BCD code can be latched at the usual high point. LT is the control terminal of lamp test inverter, and BI is the control terminal of blanking inverter. There is a pin diagram, but I can't upload it. There's nothing I can do.