Pulse generation using 555

[prachin]

Hello,

This is Prachin Patil. I am trying to generate pulses of 38khz using IR led. For that I have used NE555P IC. I am getting pulses upto14 Khz. But above it, 555 does not give any response. Now I have conncected C=0.01uf, Ra=Rb=2.2kohm. In this case I should get pulses with frequency nearly 21 Khz but it's not happening. Is NE555P not suitable for pulse generation more than 15 khz?. Can anyone suggest me regarding same?.  If possible suggest me another IC for high frequency pulse generation. Thanks in advance.

[Vara Ashishkumar]

Frequency Accuracy depends on Exactly matched value of Resistor.So connect potentiometer with Ra and adjust value as per your requirement.

[prachin]

Thank you Mr. Ashish  for your valuable response.

I have already done this with help of POT. I will try it one more time.

[prachin]

Thank you Mr. Ashish once again.

As per your information I tried it one more time with the help of POT at place of Ra & Rb. Now I am getting 38 Khz pulses.

Thanks a lot.

[Ashutosh Bhatt]

calculate values of Ra, Rb and C from equation

f = 1.44 / (Ra + 2Rb)*C

where f = 38 KHz

take C = 0.01 uFd

[prachin]

Thank you so much Mr. Bhutt for your valuable response.

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