74123
器件描述：Dual Retriggerable One-Shot with Clear and Complementary Outputs
器件厂商：FAIRCHILD [Fairchild Semiconductor]
文件大小：56.88KB，共5页
Sponsor by e络盟器件资料摘要：
© 2000 Fairchild Semiconductor Corporation DS006539 www.fairchildsemi.com
August 1986
Revised March 2000
DM74123
Dual
Ret
r
i
ggerabl
e
O
n
e
-
Shot
wit
h
C
l
ear
and
Com
p
lementa
r
y
O
u
t
put
s
DM74123
Dual Retriggerable One-Shot with
Clear and Complementary Outputs
General Description
The DM74123 is a dual retriggerable monostable multi-
vibrator capable of generating output pulses from a few
nano-seconds to extremely long duration up to 100% duty
cycle. Each device has three inputs permitting the choice of
either leading-edge or trailing edge triggering. Pin (A) is an
active-LOW transition trigger input and pin (B) is an active-
HIGH transition trigger input. A LOW at the clear (CLR)
input terminates the output pulse: which also inhibits trig-
gering. An internal connection from CLR to the input gate
makes it possible to trigger the circuit by a positive-going
signal on CLR as shown in the Truth Table.
To obtain the best and trouble free operation from this
device please read the Operating Rules as well as the
One–Shot Application Notes carefully and observe recom-
mendations.
Features
a73 DC triggered from active-HIGH transition or active-LOW
transition inputs
a73 Retriggerable to 100% duty cycle
a73 Direct reset terminates output pulse
a73 Compensated for V
CC
and temperature variations
a73 DTL, TTL compatible
a73 Input clamp diodes
Ordering Code:
Connection Diagram Triggering Truth Table
H = HIGH Voltage Level
L = LOW Voltage Level
X = Immaterial
Functional Description
The basic output pulse width is determined by selection of
an external resistor (R
X
) and capacitor (C
X
). Once trig-
gered, the basic pulse width may be extended by retrigger-
ing the gated active-LOW transition or active-HIGH
transition inputs or be reduced by use of the active-LOW
transition clear input. Retriggering to 100% duty cycle is
possible by application of an input pulse train whose cycle
time is shorter than the output cycle time such that a con-
tinuous “HIGH” logic state is maintained at the “Q” output.
Order Number Package Number Package Description
DM74123N N16E 16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Inputs
Response
ABCLR
X X L No Trigger
c16 L X No Trigger
c16 H H Trigger
H c17 X No Trigger
L c17 H Trigger
LHc17 Trigger
August 1986
Revised March 2000
DM74123
Dual
Ret
r
i
ggerabl
e
O
n
e
-
Shot
wit
h
C
l
ear
and
Com
p
lementa
r
y
O
u
t
put
s
DM74123
Dual Retriggerable One-Shot with
Clear and Complementary Outputs
General Description
The DM74123 is a dual retriggerable monostable multi-
vibrator capable of generating output pulses from a few
nano-seconds to extremely long duration up to 100% duty
cycle. Each device has three inputs permitting the choice of
either leading-edge or trailing edge triggering. Pin (A) is an
active-LOW transition trigger input and pin (B) is an active-
HIGH transition trigger input. A LOW at the clear (CLR)
input terminates the output pulse: which also inhibits trig-
gering. An internal connection from CLR to the input gate
makes it possible to trigger the circuit by a positive-going
signal on CLR as shown in the Truth Table.
To obtain the best and trouble free operation from this
device please read the Operating Rules as well as the
One–Shot Application Notes carefully and observe recom-
mendations.
Features
a73 DC triggered from active-HIGH transition or active-LOW
transition inputs
a73 Retriggerable to 100% duty cycle
a73 Direct reset terminates output pulse
a73 Compensated for V
CC
and temperature variations
a73 DTL, TTL compatible
a73 Input clamp diodes
Ordering Code:
Connection Diagram Triggering Truth Table
H = HIGH Voltage Level
L = LOW Voltage Level
X = Immaterial
Functional Description
The basic output pulse width is determined by selection of
an external resistor (R
X
) and capacitor (C
X
). Once trig-
gered, the basic pulse width may be extended by retrigger-
ing the gated active-LOW transition or active-HIGH
transition inputs or be reduced by use of the active-LOW
transition clear input. Retriggering to 100% duty cycle is
possible by application of an input pulse train whose cycle
time is shorter than the output cycle time such that a con-
tinuous “HIGH” logic state is maintained at the “Q” output.
Order Number Package Number Package Description
DM74123N N16E 16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Inputs
Response
ABCLR
X X L No Trigger
c16 L X No Trigger
c16 H H Trigger
H c17 X No Trigger
L c17 H Trigger
LHc17 Trigger