74HC259 Datasheet, PDF (5/11 Pages) NXP Semiconductors – 8-bit addressable latch

Philips Semiconductors
8-bit addressable latch
Product specification
74HC/HCT259
FUNCTION TABLE
OPERATING
MODES
master reset
INPUTS
OUTPUTS
MR LE D A₀ A₁ A₂ Q₀ Q₁ Q₂ Q₃ Q₄ Q₅ Q₆ Q₇
L HXXXXL
L
L
L
L
L
L
L
demultiplex
(active HIGH)
decoder
(when D = H)
L L d L L L Q=d L
L
L
L
L
L
L
L L d HL L L
Q=d L
L
L
L
L
L
L L d L HL L
L
Q=d L
L
L
L
L
L L d HHL L
L
L
Q=d L
L
L
L
L L d L L HL
L
L
L
Q=d L
L
L
L L d HL HL
L
L
L
L
Q=d L
L
L L d L HHL
L
L
L
L
L
Q=d L
L L d HHHL
L
L
L
L
L
L
Q=d
store (do nothing) H H X X X X q₀ q₁ q₂ q₃ q₄ q₅ q₆ q₇
HL
d
L
L
L
Q=d q₁
q₂
q₃
q₄
q₅
q₆
q₇
HL
d
HL
L
q₀
Q=d q₂
q₃
q₄
q₅
q₆
q₇
HL
d
L
HL
q₀
q₁
Q=d q₃
q₄
q₅
q₆
q₇
HL
d
HHL
q₀
q₁
q₂
Q=d q₄
q₅
q₆
q₇
addressable latch
HL
d
L
L
H q₀
q₁
q₂
q₃
Q=d q₅
q₆
q₇
HL
d
HL
H q₀
q₁
q₂
q₃
q₄
Q=d q₆
q₇
HL
d
L
H H q₀
q₁
q₂
q₃
q₄
q₅
Q=d q₇
HL
d
H H H q₀
q₁
q₂
q₃
q₄
q₅
q₆
Q=d
Notes
1. H = HIGH voltage level
L = LOW voltage level
X = don’t care
d = HIGH or LOW data one set-up time prior to the LOW-to-HIGH LE transition
q = lower case letters indicate the state of the referenced output established during the last cycle in which it was
addressed or cleared
December 1990
5