Datasheet

SN54HC646, SN74HC646
OCTAL BUS TRANSCEIVERS AND REGISTERS
WITH 3-STATE OUTPUTS
SCLS150C – DECEMBER 1982 – REVISED MARCH 2003
8
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
switching characteristics over recommended operating free-air temperature range, C
L
= 150 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 90 265 400 330
CLKBA or CLKAB A or B
4.5 V 24 53 80 66
6 V 20 46 68 57
2 V 70 220 335 280
t
pd
A or B B or A
4.5 V 20 44 67 56
ns
6 V 15 38 57 49
†
2 V 80 275 415 345
SBA or SAB
†
A or B
4.5 V 24 55 83 69
6 V 20 47 70 60
2 V 113 330 500 410
OE A or B
4.5 V 33 66 100 82
t
6 V 27 57 85 71
ns
t
en
2 V 113 330 500 410
ns
DIR A or B
4.5 V 33 66 100 82
6 V 27 57 85 71
2 V 45 210 315 265
t
t
Any
4.5 V 17 42 63 53
ns
6 V 13 36 53 43
†
These parameters are measured with the internal output state of the storage register opposite that of the bus input.
operating characteristics, T
A
= 25°C
PARAMETER TEST CONDITIONS TYP UNIT
C
pd
Power dissipation capacitance No load 50 pF
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