On 28 Oct 2010 at 0:26, John Honniball wrote:
On the subject of binary to hex 7-segment decoders, has anyone
ever seen a DM9368? ISTR that it's a pre-programmed PROM of
some kind, taking in four bits of binary (plus some ripple
blanking pins) and outputting 7-segment drive signals for
0-9 and A-F.
No, there's a latch in there also. As I mentioned yesterday, it's
part of the Fairchild 9368/9370/9374 series.
As a pure ROM, you may be thinking of the MC4039, which, by
Motorola's admission, was nothing but a preprogrammed version of the
XC170 128-bit mask ROM. Circa 1969.
The same ROM was used as the MC4001 BCD-to-Binary/Binary-to-BCD
encoder.
--Chuck