Hi All,
I'm pretty sure this is easy but I'm not experienced enough to actually know how to do it:
I want to remotely monitor the charging of a 12V battery using a digital output that I have available. My idea is when the battery is charging it will see >13V and when it is not charging it will see <13V. So, I'd like the digital output to go high at >13V and low at <13V. This circuit will be powered by the same 12V battery it's measuring so current use should be minimal, particularly when the battery's not charging.
If my battery is charging, I would expect to see the digital signal go high and if it is not, I would expect to see low. (I imagine ~5V would be sufficient to trigger the digital high; ~12V would be good.)
I've been reading about crowbars using SCRs which sound OK (using a zener diode to activate the SCR and a bunch of resistors to keep the current reasonable) but the problem seems to be the SCR would only activate once, then stay on! Not quite what I had in mind...
Thoughts? Suggestions?
Many thanks.
I'm pretty sure this is easy but I'm not experienced enough to actually know how to do it:
I want to remotely monitor the charging of a 12V battery using a digital output that I have available. My idea is when the battery is charging it will see >13V and when it is not charging it will see <13V. So, I'd like the digital output to go high at >13V and low at <13V. This circuit will be powered by the same 12V battery it's measuring so current use should be minimal, particularly when the battery's not charging.
If my battery is charging, I would expect to see the digital signal go high and if it is not, I would expect to see low. (I imagine ~5V would be sufficient to trigger the digital high; ~12V would be good.)
I've been reading about crowbars using SCRs which sound OK (using a zener diode to activate the SCR and a bunch of resistors to keep the current reasonable) but the problem seems to be the SCR would only activate once, then stay on! Not quite what I had in mind...
Thoughts? Suggestions?
Many thanks.