MC74AC646DWR2G Datasheet, PDF (1/11 Pages) ON Semiconductor – Octal Transceiver/Register with 3−State Outputs (Non−inverting)

MC74AC646, MC74ACT646
Octal Transceiver/Register
with 3−State Outputs
(Non−inverting)
The MC74AC646/74ACT646 consist of registered bus transceiver
circuits, with outputs, D−type flip−flops and control circuitry
providing multiplexed transmission of data directly from the input bus
or from the internal storage registers. Data on the A or B bus will be
loaded into the respective registers on the LOW−to−HIGH transition
of the appropriate clock pin (CAB or CBA). The four fundamental
data handling functions available are illustrated Figures 1 to 4.
• Independent Registers for A and B Buses
• Multiplexed Real−Time and Stored Data Transfers
• Choice of True and Inverting Data Paths
• 3−State Outputs
• 300 mil Slim Dual In−Line Package
• Outputs Source/Sink 24 mA
• ′ACT646 Has TTL Compatible Inputs
w These devices are available in Pb−free package(s). Specifications herein
apply to both standard and Pb−free devices. Please see our website at
www.onsemi.com for specific Pb−free orderable part numbers, or
contact your local ON Semiconductor sales office or representative.
REAL TIME TRANSFER
A-BUS TO B-BUS
A-BUS
REAL TIME TRANSFER
B-BUS TO A-BUS
A-BUS
REG
REG
REG
REG
B-BUS
Figure 1.
B-BUS
Figure 2.
http://onsemi.com
24
1
24
1
PDIP−24
N SUFFIX
CASE 724
SO−24
DW SUFFIX
CASE 751E
MARKING DIAGRAMS
PDIP−24
MC74AC646N
AWLYYWW
MC74ACT646N
AWLYYWW
SO−24
AC646
AWLYYWW
ACT646
AWLYYWW
STORAGE
FROM BUS TO REGISTER
A-BUS
REG
REG
B-BUS
Figure 3.
TRANSFER
FROM REGISTER TO BUS
A-BUS
REG
REG
B-BUS
Figure 4.
A
= Assembly
Location
L, WL = Wafer Lot
Y, YY = Year
W, WW = Work Week
ORDERING INFORMATION
Device
Package Shipping
MC74AC646N
PDIP−24 15 Units/Rail
MC74ACT646N
PDIP−24 15 Units/Rail
MC74AC646DW
MC74AC646DWR
2
MC74ACT646DW
SOIC−24 30 Units/Rail
SOIC−24 1000 Tape & Reel
SOIC−24 30 Units/Rail
MC74ACT646DWR2 SOIC−24 1000 Tape & Reel
© Semiconductor Components Industries, LLC, 2006
1
March, 2006 − Rev. 6
Publication Order Number:
MC74AC646/D