Building a 555 Astable Oscillator: Achieving 50KHz Output

Click For Summary
SUMMARY

The forum discussion centers on building a 555 astable oscillator to achieve a 50 KHz output. The user initially used R1 = 98 ohms, R2 = 67 ohms, and a capacitor of 100nF, resulting in a calculated frequency of 62 KHz. After troubleshooting, it was determined that using resistors above 1K is recommended to stabilize the output, and the user successfully adjusted their components to R1 = 1488 ohms, R2 = 4754 ohms, and C1 = 2.2 nF, which improved the output signal. The discussion also highlighted the importance of using a pull-up resistor and the need for proper measurement techniques with oscilloscopes.

PREREQUISITES
  • Understanding of 555 timer IC functionality
  • Basic knowledge of RC circuit design
  • Familiarity with oscilloscopes, specifically Rigol 2072
  • Ability to read and interpret electronic schematics
NEXT STEPS
  • Learn about 555 timer IC specifications and variations, including CMOS and bipolar types
  • Explore LTSpice for simulating circuit designs before physical implementation
  • Research the effects of component tolerances on oscillator performance
  • Investigate methods for amplifying low output signals from oscillators
USEFUL FOR

Electronics enthusiasts, hobbyists building oscillators, and engineers looking to optimize 555 timer circuits will benefit from this discussion.

  • #31
helofrind said:
So I built a 555 astable oscillator. I wanted to get 50 KHz on my output, which I have achieved, but the values of my components do not match the formula I have calculated. I have:
R1 = 98 ohms
R2 = 67 ohms
Cap = 100nF
So I have:
1.44/(98 + 2 67) 100nF
Which should be 62KHz. Also can anyone explain why I am getting 1volt on output with 5 volts in. Thanks in advance for any help.

Have you tested the 555 itself? For instance, if you swap your current chip with another keeping all other components, does it behave exactly the same? The one volt output from 5V in seems strange. BTW, without having the 555 specs in front of me, I wonder if 5V is within the specified Vpower of the chip. Is it at the lower limit of specified voltage? Did you measure the Vpower IN CIRCUIT, or did you assume that was 5V because you used a 5V supply? Are you using the LM555, a CMOS or multiple 555 on a chip version? I'm just casting about here, since I don't know more about your circuit.
 
Engineering news on Phys.org
  • #32
Sorry about my redundant post. Somehow, I thought there was only 1 reply...
 

Similar threads

Trouble with high frequency astable multivibrator
  • · Replies 44 ·
2
Replies
44
Views
7K
Trouble building a Buck Converter
  • · Replies 14 ·
Replies
14
Views
2K
RC Phase Shift Oscillator not Oscillating
  • · Replies 41 ·
2
Replies
41
Views
7K
I tried building an induction coil
  • · Replies 34 ·
2
Replies
34
Views
3K
Building a Buck Converter Using the LT1170
  • · Replies 10 ·
Replies
10
Views
3K
555 timer, 50% duty cycle astable, run from 5V
  • · Replies 38 ·
2
Replies
38
Views
23K
Build a Lightning Cloud with a 555 Timer | LED Flashing Help
  • · Replies 16 ·
Replies
16
Views
3K
Solving 555 Based Switcher Challenge for Niхie Clock
  • · Replies 44 ·
2
Replies
44
Views
5K
Monostable and Astable multivibrator using 555 timer.
  • · Replies 8 ·
Replies
8
Views
7K
Question about power supply output parasitics (scope shots attached)
  • · Replies 37 ·
2
Replies
37
Views
5K