NE555 Astable Multivibrator Frequency and Duty Cycle Calculator
See our other Electronics
Calculators.
This calculator computes the resistors and
capacitors for a NE555 timer chip, which has been configured as a astable
multivibrator (oscillator), or square wave generator. Just enter in the
duty cycle and the frequency and the calculator will compute reasonable
values for the resistors and capacitors.
Note that the minimum duty
cycle is 50 percent, so if you need a smaller duty cycle you need to use
an inverter on the output.
Also the design equations of the timer are
just approximations that can be off by as much as 20% from the empirical
results.
Equations:
F=1/T= 1.44/((RA+RB*2)*C)
TL= 0.693*RB*C
TH= 0.693*(RA+RB)*C
D= Duty Cycle= (RA+RB)/(RA+2*RB)
Or,
RA= 1.44**(2*D-1)/(F*C)
RB= 1.44*(1-D)/(F*C)
IC Manufacturer Links
The best way to find integrated circuits (ICs) is to
use our free Electronics
Component Directory, where a myriad of electronics manufactures are
listed.
Other Electronics Links
We offer a broad range of electrical
engineering calculators and electronics
articles and tutorials.
Daycounter specializes in contract
electronics design. Do you need some help on your project? Contact
us to get a quote.
[Employment]
[Downloads]
[Articles]
[Contact Us]
Salt Lake City, UT, USA
Disclaimer: Daycounter, Inc. doesn't guarantee the accuracy of any of it's content. Use at your own risk.
© Copyright 2016 Daycounter, Inc. All rights Reserved.
|
