Can the 555 timer be set to its maximum frequency of 500kHz?

In summary: As always, the datasheet will tell you what you need to know.Summary: In summary, the conversation discusses how to program a 555 timer to produce pulses at a certain frequency and duty cycle. The recommended method is to read the datasheet for the 555 timer, which provides equations and diagrams for configuring the circuit. The conversation also mentions the use of resistors and capacitors to control the time properties of the pulses. The datasheet also suggests that some 555 timers may not work well at frequencies above 500kHz.
  • #1
Beckman44
9
0
How would i do this?
 
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  • #2
What does this even mean?

- Warren
 
  • #3
sorry if this was not understandable...here i go again...
how would i program a 555 timer so when i activate it it tells something else that it is doing a certain action many times.

Ex. Holding down a button and Xbox Controller shooting as fast as possible
 
  • #4
a better question would be how do you adjust the rate of a 555 timers pulses?
 
  • #5
You should consider reading the 555's datasheet.

- Warren
 
  • #6
where could i find this?
 
  • #8
what will the data sheet do for me?
 
  • #9
It'll teach you how to configure the circuit to produce any kind of pulses you want. Look in the Applications section.

- Warren
 
  • #11
You've got to be kidding me. I gave you a link to a Google search of the words "555 datasheet." The very first link points you to a datasheet:

http://www.national.com/ds.cgi/LM/LM555.pdf

- Warren
 
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  • #12
i can't just use a pot?
 
  • #13
Beckman44, you really need to spend at least a bit of time doing your own reading. The datasheet will tell you everything you need to know to calculate R and C values to get whatever frequency and duty cycle you'd like. The datasheet is the ultimate document from which to learn how to use an electronic device. If you can't understand the datasheet, or if you try to use what you've learned and still can't get it to work as you'd like, then come ask questions. Spend an hour, read the datasheet's Applications section a few times over, and then come back if you still need help.

- Warren
 
  • #14
i don't know if I am misunderstanding or u...but is lm555(used int he guide) the same as cmos 555 timer? i mean do they change the same?...and i see nothing in there telling how to actually change the chip itself...it says how to get a rate but now how YOU change the chip...What materials you neeed.
 
  • #15
Beckman44,

Every "555" timer, from every manufacturer, is going to operate the same way. They're known as "second source" parts, and are functionally identical.

I don't know what you mean by "changing the chip." To configure a 555 timer, you connect some capacitors and resistors to it. The values of these components determines the frequency of the oscillation, etc.

You need to ask more detailed questions if you want more detailed answers.

- Warren
 
  • #16
Hi Everyone ,
Beckman44 , I Understand That you need to produce pulses as fast as possible , So you need to use an astable circuit like the one in the attachments .
There are Some Equations Control The Properties of the pulses and they are :
( The frequency Equation )

[tex]\[
f = \frac{{1.44}}{{C(R_1 + 2R_2 )}}
\][/tex]

( The Period Equation )

[tex]\[
\tau = \frac{1}{f} = \frac{{C(R_1 + 2R_2 )}}{{1.44}}
\][/tex]

( The Duty Cycle Equation )

[tex]\[
Duty{\rm }Cycle = \frac{{R_1 + R_2 }}{{R_1 + 2R_2 }}
\][/tex]

You See That the Resistors and the Capacitor Control The Time Properties of the pulses , So by the good Choise of them you can get any pulses you want .
 

Attachments

  • 555Timer.GIF
    555Timer.GIF
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  • #17
I agree with chroot that it's good to become familiar with looking at datasheets. In the National datasheet, what you want starts on p. 7 under "ASTABLE OPERATION":

http://www.national.com/ds/LM/LM555.pdf

Figs. 4 and 6 are particularly relevant, as is the equation for "f=..." on p. 8.
 
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  • #18
Just an FYI, many 555s don't work so well starting at around 500kHz.
 

1. How do I set a 555 timer to its maximum value?

The maximum value for a 555 timer is determined by the resistor and capacitor values used in the circuit. To set it to its maximum value, use a large resistor (around 1MΩ) and a large capacitor (around 100µF) in your circuit.

2. What is the maximum frequency of a 555 timer?

The maximum frequency of a 555 timer is determined by the values of the resistor and capacitor used in the circuit. It can range from a few Hertz to several Megahertz.

3. How do I calculate the maximum time delay for a 555 timer?

To calculate the maximum time delay for a 555 timer, use the formula T = 1.1*R*C, where T is the time in seconds, R is the resistance in ohms, and C is the capacitance in Farads.

4. Can I set a 555 timer to a specific maximum value?

Yes, you can set a 555 timer to a specific maximum value by choosing the appropriate resistor and capacitor values for your desired frequency or time delay. You can also use a potentiometer to adjust the values and fine-tune the maximum value.

5. Is it possible to change the maximum value of a 555 timer after it has been set?

Yes, the maximum value of a 555 timer can be changed by adjusting the resistor and capacitor values in the circuit. However, this may require reconfiguring the entire circuit, so it is best to determine the desired maximum value before setting up the circuit.

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