August 1986
Revised May 2000
DM74S373 • DM74S374
3-STATE Octal D-Type Transparent Latches
and Edge-Triggered Flip-Flops
Schmitt-trigger buffered inputs at the enable/clock lines
simplify system design as ac and dc noise rejection is
improved by typically 400 mV due to the input hysteresis. A
buffered output control input can be used to place the eight
outputs in either a normal logic state (HIGH or LOW logic
levels) or a high-impedance state. In the high-impedance
state the outputs neither load nor drive the bus lines signifi-
cantly.
General Description
These 8-bit registers feature totem-pole 3-STATE outputs
designed specifically for driving highly-capacitive or rela-
tively low-impedance loads. The high-impedance 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 bus-organized system without need for inter-
face or pull-up components. They are particularly attractive
for implementing buffer registers, I/O ports, bidirectional
bus drivers, and working registers.
The output control does not affect the internal operation of
the latches or flip-flops. That is, the old data can be
retained or new data can be entered even while the outputs
are OFF.
The eight latches of the DM74S373 are transparent D-type
latches meaning that while the enable (G) is HIGH the Q
outputs will follow the data (D) inputs. When the enable is
taken LOW the output will be latched at the level of the
data that was set up.
Features
■ Choice of 8 latches or 8 D-type flip-flops in a single
package
The eight flip-flops of the DM74S374 are edge-triggered D-
type flip-flops. On the positive transition of the clock, the Q
outputs will be set to the logic states that were set up at the
D inputs.
■ 3-STATE bus-driving outputs
■ Full parallel-access for loading
■ Buffered control inputs
■ P-N-P input reduce D-C loading on data lines
Ordering Code:
Order Number Package Number
Package Description
DM74S373WM
DM74S373N
DM74S374WM
DM74S374N
M20B
N20A
M20B
N20A
20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Devices also available in Tape and Reel. Specify by appending the suffix letter “X” to the ordering code.
Connection Diagrams
DM74S374N
DM74S373N
© 2000 Fairchild Semiconductor Corporation
DS006486
www.fairchildsemi.com