Is there any alternate way to design Astable Multi Vibrator with use of only Resistor & capacitor ? ( avoid 555 Timer ) , avoid BJT if possible.
my aim to make most compact Astable MV.
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1\$\begingroup\$ No - you cannot make something switch on and off with only passive components. \$\endgroup\$– Greg d'EonMar 11, 2015 at 12:37
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\$\begingroup\$ There are lots of ocillator designs but they all require active components of some sort. I could use an opamp, transistors, 555 timer etc. But you can not make one with only Resistors, Capacitors and Inductors. \$\endgroup\$– Warren HillMar 11, 2015 at 12:42
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An astable multivibrator consists of two amplifying stages cross-connected in a positive feedback loop along with two RC coupling networks. Therefore it requires active components such as BJTs or MOSFETs, and canot be made from just a combination of passive components such as resistors and capacitors.
This is about as simple as it gets (classic astable circuit):
The active elements (BJTs or whatever) are required to control the alternate charging and discharging of the capacitors that (along with their associated resistors) control the period of the oscillation. Carefully read the Operation section in the article you linked to for more information.
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\$\begingroup\$ I agree but still if any ckt without BJT is more welcomed. \$\endgroup\$ Mar 11, 2015 at 9:11
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2\$\begingroup\$ Did you read what he said? What part of "requires active components" is so hard to understand? \$\endgroup\$– lyndonMar 11, 2015 at 11:44