555 timer 50% duty cycle question

Hi, does anyone know how I could get a 555 timer to operate in astable mode at a 50% duty cycle? All the circuits I've seen are always for
greater than 50%. thanks.
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panfilero wrote:

if you look at how the standard circuit works, you will see that, whilst it discharges the timing capacitor through a single resistor, it charges it through that resistor plus a further one. Hence the time to charge is greater than the time to discharge.
Just alter the circuit so that it charges and discharges through the same total resistance. Hint: This will require an additional resistor.
However, if you want an accurate 50% duty cycle, you really need to add a divide by two to the output.
--
Sue




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There are different ways to do it: . Connect the charging resistor not to Vcc but to the output . Use diodes to have different paths for charging and discharging The circuits are available on the Net. Just google for it. Gene
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