tc74vhc123af TOSHIBA Semiconductor CORPORATION, tc74vhc123af Datasheet - Page 3

• Manufacturer Part Number: tc74vhc123af
• Description: Dual Monostable Multivibrator
• Manufacturer: TOSHIBA Semiconductor CORPORATION

Block Diagram (Note 1) (Note 2)
Note 1: C
Note 2: External clamping diode, D
A
B
Capacitor, resistor, and diode, respectively.
The external capacitor is charged to V
If the supply voltage is turned off, C
sufficiently large and V
current or latch-up. If the capacitance of the supply voltage filter is large enough and V
in rush current is automatically limited and damage to the IC is avoided.
The maximum value of forward current through the parasitic diode is ±20 mA.
In the case of a large C
In the even a system does not satisfy the above condition, an external clamping diode (D
protect the IC from rush current.
X
, R
1
2
t
(t
f
X
f
≥ (V
, D
is the time between the supply voltage turn off and the supply voltage reaching 0.4 V
X
CC
are external
14
− 0.7) C
C
C
X
X
3
CLR
15
R
X
X
/C
CC
X
/20 mA
X
, the limit of fall time of the supply voltage is determined as follows:
D
R
drops rapidly, there will be some possibility of damaging the IC through in rush
X
X
X
13
;
4
Q
Q
V
X
CC
is discharges mainly through the internal (parasitic) diode. If C
CC
level in the wait state, i.e. when no trigger is applied.
3
A
B
TC74VHC123,221AF/AFN/AFT/AFK
10
9
6
C
C
X
X
11
CLR
R
7
X
/C
X
D
R
X
X
12
5
Q
Q
V
CC
CC
X
drops slowly, the
) is needed to
CC
2006-06-01
.)
X
is