berres
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Hi all
I know this component might be considered as digital but "embedded systems and real time OS" didn't feel like the right category to create the thread in either... sry if I placed it incorrectly..
Why I need a multivibrator:
I'm working on a project where two sensors is going to trigger another circuit or microcontroller and the output pulse has to be hold active (high) for like 2sec at least.
The sensors will sense direction and I've built a circuit using 2 retriggerable monostable multivibrators where only one multivibrator can be triggered at a time. So if sensor 1 triggers multivibrator 1 then multivibrator 2 cannot be triggered while multivibrator 1 is active and it could only be triggered when multivibrator 1 has turned to its stable state (low) again (and if it is first of the two to trigger of course).
However all multivibrators I can find consumes at least 4uA when not active and 160uA when active (74VHC123A for instance). For my application this is by far too much and I've tried to build a one shot my self. I've tested the circuits in the following links:
https://www.electronics-tutorials.ws/sequential/seq_3.html
https://www.electronics-tutorials.ws/waveforms/monostable.html
The problem with these is that the period of the trigger pulses has to be greater than the time RC time constant of the multivibrator. The sensors will for sure be triggered with a period lower than the RC time constant (of 2sec) so these solutions will not work.
Do anyone have schematics for such a multivibrator (have to be a retriggerable also)?
Thanks for taking time reading this!
I know this component might be considered as digital but "embedded systems and real time OS" didn't feel like the right category to create the thread in either... sry if I placed it incorrectly..
Why I need a multivibrator:
I'm working on a project where two sensors is going to trigger another circuit or microcontroller and the output pulse has to be hold active (high) for like 2sec at least.
The sensors will sense direction and I've built a circuit using 2 retriggerable monostable multivibrators where only one multivibrator can be triggered at a time. So if sensor 1 triggers multivibrator 1 then multivibrator 2 cannot be triggered while multivibrator 1 is active and it could only be triggered when multivibrator 1 has turned to its stable state (low) again (and if it is first of the two to trigger of course).
However all multivibrators I can find consumes at least 4uA when not active and 160uA when active (74VHC123A for instance). For my application this is by far too much and I've tried to build a one shot my self. I've tested the circuits in the following links:
https://www.electronics-tutorials.ws/sequential/seq_3.html
https://www.electronics-tutorials.ws/waveforms/monostable.html
The problem with these is that the period of the trigger pulses has to be greater than the time RC time constant of the multivibrator. The sensors will for sure be triggered with a period lower than the RC time constant (of 2sec) so these solutions will not work.
Do anyone have schematics for such a multivibrator (have to be a retriggerable also)?
Thanks for taking time reading this!