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Three input OR alarm. 2 with 1.5volt on-state;1 with compar. output

Three input OR alarm. 2 with 1.5volt on-state;1 with compar. output

Three input OR alarm. 2 with 1.5volt on-state;1 with compar. output

(OP)
I need to disable a fuel solenoid on a diesel engine when one of 3 OR'd LED signals is in alarm.
1st monitored LED signal (oil pressure low).on state= 1.5vdc
2nd monitored LED signal (no alternator output). on state=1.3vdc
3rd signal is (coolant temperature). Must have add'l circuit to monitor for voltage drop across x-ducer and create alarm condition when voltage drop is less than 5.5volts dc.

Conditions:
1.Alarm signals may be from a flashing LED i.e.pulsing 1.5v state.
2.All LEDs must be OFF 1st before alarm circuit is enabled.
                              Thanks to anyone who can help.

3.solenoid is 12vdc ~100mA.

RE: Three input OR alarm. 2 with 1.5volt on-state;1 with compar. output

it is a fairly straight forward one to sort if you can program  a simple micro like a

RE: Three input OR alarm. 2 with 1.5volt on-state;1 with compar. output

I can think of at lease 4 ways to do this.  We first need to look at your requirements:
How much should the circuit cost? (nothing and as little as possible  are not options)
How much have you to spend on doing the design?
Do you want a Hardware solution? - requirements are stable with time.  Hardware is expensive to change but, in most cases less expensive to implement)
Do you want a Software based solution? - Requirements may change over time. (PIC, 8051, ***)
I will follow thread to see if I can help.

RE: Three input OR alarm. 2 with 1.5volt on-state;1 with compar. output

You'll get an answer to your question at www.smtnet.com. ; All the heavy shooters are working at that forum and have been for at east 3 years.
Good Luck!

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