Datasheet

SN54HC646, SN74HC646
OCTAL BUS TRANSCEIVERS AND REGISTERS
WITH 3-STATE OUTPUTS
SCLS150C – DECEMBER 1982 – REVISED MARCH 2003
7
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
switching characteristics over recommended operating free-air temperature range, C
L
= 50 pF
(unless otherwise noted) (see Figure 2)
PARAMETER
FROM TO
V
CC
T
A
= 25°C SN54HC646 SN74HC646
UNIT
PARAMETER
(INPUT) (OUTPUT)
V
CC
MIN TYP MAX MIN MAX MIN MAX
UNIT
2 V 6 11 4.4 5.5
f
max
4.5 V 31 54 22 27
MHz
6 V 36 64 25 31
2 V 65 180 270 225
CLKBA or CLKAB A or B
4.5 V 18 36 54 45
6 V 14 31 46 38
2 V 50 135 205 170
t
pd
A or B B or A
4.5 V 14 27 41 34
ns
6 V 11 23 35 29
†
2 V 70 190 285 240
SBA or SAB
†
A or B
4.5 V 20 38 57 48
6 V 16 32 48 41
2 V 85 245 370 305
t
en
OE A or B
4.5 V 25 49 74 61
ns
6 V 20 42 63 52
2 V 85 245 370 305
t
dis
OE A or B
4.5 V 25 49 74 61
ns
6 V 20 42 63 52
2 V 80 245 370 305
t
en
DIR A or B
4.5 V 25 49 74 61
ns
6 V 20 42 63 52
2 V 80 245 370 305
t
dis
DIR A or B
4.5 V 25 49 74 61
ns
6 V 20 42 63 52
2 V 28 60 90 75
t
t
Any
4.5 V 8 12 18 15
ns
6 V 6 10 15 13
†
These parameters are measured with the internal output state of the storage register opposite that of the bus input.
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