© 2000 Fairchild Semiconductor Corporation DS006223 www.fairchildsemi.com
April 1984
Revised February 2000
DM74ALS534 Octal D-Type Edge-Tr iggered Flip-Flop with 3-STATE Outputs
DM74ALS534
Octal D-Type Edge-Triggered Flip-Flop
with 3-STATE Outputs
General Description
These 8-bit register s feature totem-pole 3- STATE outputs
designed specifically fo r driving highly-capacitive or relatively low-impedance loa ds. Th e hi gh -im ped ance state and
increased high-logic-level drive provide these registers with
the capability of being connected directly to and driving the
bus lines in a bu s-or ga nized sy stem w ith ou t n eed fo r interface or pull-up components. They are parti cularly attractive
for implementing buffer registers, I/O ports, bidirectional
bus drivers, and working registers.
The eight flip-flops of the DM74ALS534 are edg e- trigg er ed
inverting D-type flip- flops. On the posi tive transition of t he
clock, the Q outputs will be set to the complement of the
logic states that were set up at the D inputs.
A buffered output control input ca n be used to place the
eight outputs in either a normal l ogic state (HIGH or LOW
logic levels) or a high-impedance state. In the high-impedance state the outputs ne ither load nor dr ive the bus lines
significantly.
The output control does not affect the i nternal oper ation of
the flip-flops. That is, the old data can be retained or new
data can be entered even while the outputs are off.
Features
■ Switching specifications at 50 pF
■ Switching specifications guaranteed over full tempera-
ture and V
CC
range
■ Advanced oxide-isolated, ion-implanted Schottky TTL
process
■ 3-STATE buffer-type outputs drive bus lines directly
Ordering Code:
Devices also availab le in Tape and Reel. Specify by appending th e s uffix let t er “X” to the ordering code.
Connection Diagram
Order Number Package Number Package Description
DM74ALS534WM M20B 20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
DM74ALS534N N20A 20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide