DM7448N BCD-to-7-segment decoder / driver by National Semiconductor. Package: 16-DIP Popular with all Nixie tube clock designers as these chips have leading / trailing zero suppression. OK, so that means that they are rare and in demand so fetching upto £11 on ebay ( I think not ! ) so buy a set of 4 here for just £16 .... while stocks last. Download National Semiconductor DM7448N .pdf datasheet: Status: NOS (New Old Stock) ex leading UK distributor stores, in original tubes. Individually tested components: YES RoHS compliant: no