74VHC221AM Fairchild Semiconductor, 74VHC221AM Datasheet - Page 2

• Manufacturer Part Number: 74VHC221AM
• Description: MULTIVIBRATOR DUAL MONO 16SOIC
• Manufacturer: Fairchild Semiconductor
• Series: 74VHCr

Specifications of 74VHC221AM

• Logic Type: Monostable
• Independent Circuits: 2
• Schmitt Trigger Input: No
• Propagation Delay: 8.1ns
• Current - Output High, Low: 8mA, 8mA
• Voltage - Supply: 2 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-SOIC (3.9mm Width)
• Elements Per Chip: 2
• Logic Family: VHC
• Input Bias Current (max): 0.004 mA
• Propagation Delay Time: 24.1 ns, 14 ns
• High Level Output Current: - 8 mA
• Low Level Output Current: 8 mA
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 2 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Operating Supply Voltage: 2.5 V, 3.3 V, 5 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

©1994 Fairchild Semiconductor Corporation
74VHC221A Rev. 1.2
Connection Diagram
Logic Symbol
Truth Table
H
L
X = Don’t Care
A
X
H
X
L
L
LOW Voltage Level
HIGH Voltage Level
HIGH-to-LOW Transition
LOW-to-HIGH Transition
Inputs
B
H
X
H
X
L
CLR
H
H
H
H
L
IEEE/IEC
Outputs
Q
L
L
L
Q
H
H
H
Output Enable
Inhibit
Inhibit
Output Enable
Output Enable
Reset
Function
2
Block Diagrams
Note A: Cx, Rx, Dx are external Capacitor, Resistor, and
Diode, respectively.
Note B: External clamping diode, Dx;
External capacitor is charged to V
state, i.e. when no trigger is applied.
If the supply voltage is turned off, Cx discharges mainly
through the internal (parasitic) diode. If Cx is sufficiently
large and V
ity of damaging the IC through in rush current or latch-
up. If the capacitance of the supply voltage filter is large
enough and V
automatically limited and damage to the IC is avoided.
The maximum value of forward current through the para-
sitic diode is ±20 mA. In the case of a large Cx, the limit
of fall time of the supply voltage is determined as follows:
t
(t
supply voltage reaching 0.4 V
In the event a system does not satisfy the above condi-
tion, an external clamping diode (Dx) is needed to
protect the IC from rush current.
f
f
is the time between the supply voltage turn off and the
(V
CC
– 0.7) Cx / 20mA
CC
drops rapidly, there will be some possibil-
CC
drops slowly, the in rush current is
CC
)
CC
level in the wait
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