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The 74xx family of TTL ICs has several BCD to 7-segment-display chips, such as the 7446-7449, which could display digits 0-9. However, there does not seem to have been a hexadecimal to 7-segment driver in the 74xx family, which would also display the digits A-F. Why was no such chip made?

This is a historical question about the 74xx family (including variants such as 74LSxx and 74HCxx). It is not about alternative solutions, which are already discussed here and here.

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  • \$\begingroup\$ See discussion on eevblog.com/forum/beginners/…. \$\endgroup\$ – Transistor Aug 20 '19 at 17:19
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    \$\begingroup\$ This should not be on hold, because there was such a device - DM9368 - and so is not a matter of opinion. \$\endgroup\$ – henros Aug 20 '19 at 21:21
  • \$\begingroup\$ Hex wasn't much of 'thing' until after the heyday of TTL, and by then PALs, PLAs, GALs and other programmable logic made such things practical. That said, it's possible to do it in a single Silego for cheap, see here: silego.com/uploads/Products/product_588/details/… \$\endgroup\$ – hacktastical Aug 21 '19 at 2:27
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Most likely because when the 74xx series was popular, hex was not much used. Decimal: yes, Octal: yes, BCD*: yes, Hex; No.

*also have a look at "Half Carry Flag"

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  • \$\begingroup\$ you cannot display 0--15 on a 0--9 readout \$\endgroup\$ – analogsystemsrf Aug 21 '19 at 5:57

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