4543 BCD-to-7-Segment Latch/Decoder for LCD

A CD4543 CMOS integrated circuit providing a BCD to 7-segment latch, decoder and driver for LCD. Like the 4511 but designed to drive LCD segments, which need an alternating drive signal rather than DC to avoid damaging the display. Being 4000-series CMOS it runs on anything from 3 to 18 volts, which makes it far more flexible than 5V-only TTL logic and lets it work directly in battery and higher voltage circuits. It also draws almost no current when idle. The trade-off is speed: CMOS of this family is slower than 74HC logic, so it suits control, timing and teaching applications rather than fast data paths. Unused inputs must be tied to a supply rail, never left floating. Wide 3-18V supply range, unlike 5V-only TTL; Extremely low quiescent current suits battery circuits; High noise immunity from the wide logic swing; Standard 16-pin DIP fits breadboards and sockets