Evening gents,
Please see the schematic attached!
Attached I've posted a sketch of a simple diode, photodiode and BJT circuit we have in at the input of our gate driver circuitry.
Essentially, our microcontroller outputs a 20kHz square wave at some duty cycle, and this waveform is passed to the gate driver IC via a optoisolator in order to drive a motor.
The problem with our current setup is that if our microcontroller dies or hangs, the output is pulled high and the motor will be operating at 100% duty cycle.
Is there a simple solution to this problem such that when our microcontroller dies the output is pulled low instead of high?
Note that I would be able to easily invert our square wave in software if that will make any given solution easier to implement.
I look forward to hearing any suggestions, comments and thoughts you may have for me!
Thanks again!
Please see the schematic attached!
Attached I've posted a sketch of a simple diode, photodiode and BJT circuit we have in at the input of our gate driver circuitry.
Essentially, our microcontroller outputs a 20kHz square wave at some duty cycle, and this waveform is passed to the gate driver IC via a optoisolator in order to drive a motor.
The problem with our current setup is that if our microcontroller dies or hangs, the output is pulled high and the motor will be operating at 100% duty cycle.
Is there a simple solution to this problem such that when our microcontroller dies the output is pulled low instead of high?
Note that I would be able to easily invert our square wave in software if that will make any given solution easier to implement.
I look forward to hearing any suggestions, comments and thoughts you may have for me!
Thanks again!
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