Hi,
I want to build a circuit using 555 that would monitor 12V battery and turns on relay momentarily (relay ON time should be around 0.5 seconds) when the battery voltage reaches 11.8V. This circuit i would like to use for mini PC that is powered by 12 V battery directly and hibernate it by wiring the relay contact directly to power button. I know windows allows hibernation if power button is momentarily pressed when windows is running.
I have tried 555 circuit having resistor divider at Pin 2 (to create trigger at 11.8V) and RC in Pin 6 (threshold to keep output HIGH momentarily) to achieve above but it is not resulting as per my requirement. Below is what i have noticed.
1. Out put at pin 3 changes to HIGH when battery voltage drops to around 11.8V which is OK.
2. The problem is that the output remains HIGH until Pin 2 voltage becomes more than 11.8V.
For PC to go into hibernation i just wanted the output to become HIGH just for moment, say 0.5 seconds. Any suggestion from expert will be appreciated.
PS: Circuit diagram attached.
Best,
Deepak
I want to build a circuit using 555 that would monitor 12V battery and turns on relay momentarily (relay ON time should be around 0.5 seconds) when the battery voltage reaches 11.8V. This circuit i would like to use for mini PC that is powered by 12 V battery directly and hibernate it by wiring the relay contact directly to power button. I know windows allows hibernation if power button is momentarily pressed when windows is running.
I have tried 555 circuit having resistor divider at Pin 2 (to create trigger at 11.8V) and RC in Pin 6 (threshold to keep output HIGH momentarily) to achieve above but it is not resulting as per my requirement. Below is what i have noticed.
1. Out put at pin 3 changes to HIGH when battery voltage drops to around 11.8V which is OK.
2. The problem is that the output remains HIGH until Pin 2 voltage becomes more than 11.8V.
For PC to go into hibernation i just wanted the output to become HIGH just for moment, say 0.5 seconds. Any suggestion from expert will be appreciated.
PS: Circuit diagram attached.
Best,
Deepak
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