tc7mh123afk TOSHIBA Semiconductor CORPORATION, tc7mh123afk Datasheet - Page 3

• Manufacturer Part Number: tc7mh123afk
• Description: Dual Monostable Multivibrator
• Manufacturer: TOSHIBA Semiconductor CORPORATION

Block Diagram
Note 1: Cx, Rx, Dx are external capacitor, resistor, and diode, respectively.
Note 2: External clamping diode, Dx;
The external capacitor is charged to V
If the supply voltage is turned off, Cx is discharges mainly through the internal (parasitic) diode. If Cx is
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 Cx, the limit of fall time of the supply voltage is determined as follows:
In the even a system does not satisfy the above condition, an external clamping diode (Dx) is needed to
protect the IC from rush current.
A
B
t
f
> = (V
1
2
(t
f
CC
is the time between the supply voltage turn off and the supply voltage reaching 0.4 V
− 0.7)･Cx/20 mA
14
CX RX/CX
3
CLR
CC
Cx
15
drops rapidly, there will be some possibility of damaging the IC through in rush
Rx
Dx
13
4
Q
Q
CC
level in the wait state, i.e. when no trigger is applied.
V
CC
3
A
B
10
9
6
CX RX/CX
11
CLR
Cx
7
TC7MH123,221AFK
Rx
Dx
12
5
Q
Q
CC
drops slowly, the
V
CC
CC
2007-10-19
)