555 Timers - Monostable Multivibrator Configuration

After reviewing 555 timers in general, in this tutorial we go over one of the 3 common 555 timer configurations, the monostable multivibrator configuration. Josh reviews how the monstable configuration acts and goes into painstaking detail about why it acts the way it does, moving step by step through what happens internally to the 555 timer. He finishes up with a real life example using a 555 timer on a breadboard that's hooked up to an oscilloscope, showing how the timer actually works in normal conditions.

0:00 Introduction
1:44 External Monostable Configuration
3:13 Internal process
6:14 Recap of the internal process
7:46 High level review of the process
8:35 Physical circuit and performance
11:28 Overview and summary
12:02 The toast will never pop up

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[rjaph]

At 3:20, doesn't the fact that Vcc goes through R2 causes the Vcc to be reduced coz of the voltage drop across R2?

[joev]

I would like to get a short plus out after a contact closure. However, the contact will be closed much longer than the pulse. I don’t want another pulse until the switch opens an then recloses. Can I just put a small capacitor between the switch and pin 2?

[nihith]

why didn't you consider the voltage drop across the BJT when input to the BJT is high, can you please explain

[gkdresden]

It means, if you trigger the timer several times within the unstable state nothing will happen. But if one of the trigger pulses holds during the end of the unstable state another unstable state will be added. Am I right?

[bdzack]

excuse me can i ask something?
Is it right that to use this as timer we need to push and release the button constantly as animated in the video?
im sorry if this is a dumb question..