(adsbygoogle = window.adsbygoogle || []).push({}); [SOLVED] help 555 timer problem

hi all, i am designing a 555 on astable mode. it is designed to operate at 100kHz with a duty cycle of 95% ( and i get 48Khz and duty cycle 93.5%).

i calculated all the values necessary:

Ra = 12.987 kOhm

Rb = 721.5 Ohm

C = 1nF

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

i used thes formulas :

tH = 0.693*(Ra + Rb)*C

tL = 0.693*(Rb)*C

T = tH + tL

i searched everywhere and found out the max frequency is 500Khz so im not sure where the problem is....i need the 100kHz because i am designing an infrared modulator and the central frequency for my filters is 100kHz

can anyone help me thanks.

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# Help 555 timer problem

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