Specification Sheet

Voltage − 5 V/div
t − Time − 1 s/div
See Figure 22
Output A
Output B
Output C
t = 0
t
w
C = 1.1 R
C
C
C
t
w
C
t
w
B = 1.1 R
B
C
B
t
w
A = 1.1 R
A
C
A
t
w
A
t
w
B
NA555 , NE555 , SA555 , SE555
SLFS022I –SEPTEMBER 1973–REVISED SEPTEMBER 2014 www.ti.com
Typical Applications (continued)
9.2.4.1 Design Requirements
The sequential timer application chains together multiple mono-stable timers. The joining components are the 33-
kΩ resistors and 0.001- µF capacitors. The output high to low edge passes a 10-µs start pulse to the next
monostable.
9.2.4.2 Detailed Design Procedure
The timing resistors and capacitors can be chosen using this formula. t
w
= 1.1 × R × C.
9.2.4.3 Application Curves
Figure 23. Sequential Timer Waveforms
10 Power Supply Recommendations
The devices are designed to operate from an input voltage supply range between 4.5 V and 16 V. (18 V for
SE555). A bypass capacitor is highly recommended from VCC to ground pin; ceramic 0.1 µF capacitor is
sufficient.
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Product Folder Links: NA555 NE555 SA555 SE555