The TC40H259 is an 8-bit addressable lat ch
having one common input line and eight independent
output lines.
The respective bits are controlled by LATCH
SELECT inputs (A, B and C).
When CLEAR input is at "H" level and ENABLE (G)
input is at "L" level, the data is written into the
bit selected by LATCH SELECT inputs (A, B and C).
In this case, the other bits hold their previous
conditions.
When both of CLEAR input and ENABLE (G) input
go to "H" level, write of all bits is inhibited.
regardless of LATCH SELECT input, and their pre-
vious conditions are held.
When CLEAR input is set to "L" level and
ENABLE (G) input is set to "H" level, all bits are
reset to "L" level regardless of the other inputs.
The pin assignment and function of this latch
are the same as those of the LSTTL 74LS259.