a latched output required

Hi all,
I require an output from my alarm that only goes active when the alarm is in full trigger mode. I don't want the output to be active when the alarm is pre warning (ie light impact or external field on the microwave triggered).

The only outputs from the alarm is indicator flash (+12volts), siren output(+12 volts) and ground when armed(-ve).

What I require is a circuit that will latch an output (- or +) after :
A) a minimum of 4 input pulses (+ perferable, but - is do-able). The input pulses would ideally come from the indicator flash.
Or
B) a continuous input (from the siren) for 2 plus seconds to trigger the latched output. Down side of this option is a false latched output when the siren when the siren does is 4 fast pre warn chirps.

I would like the latched output to be active for approx 3 to 5 secs. If too difficult to intergrate in to the circuit design, I can use a seperate timer relay to achieve the same result.

I am wanting to use this circuit to press the speed dial button on a hidden cellphone, that rings me if the car is broken in to, but doesn't ring me if the alarm simply pre warns.
I am (and have already operating successfully) also using the same phone to remote start the car when I dial in- useful for the last run on the ski field!

Any suggestions? Or does anybody have an existing product/circuit design that does the above?

I have also added some very customized features to the alarm too-should you want details, please email me directly.

Kind Regards,
Glynn

If your only insterested in the cell being turned on when a door, hood, or the trunk is opened then this might work. You could have the siren output energize a relay that would connect the door trigger wire to phone system. Meaning, the sirens goes off sending power to relay. So if your door provides a (-) when open you could hook it up like this to a relay:

pin 85 - siren (if positive)
pin 86 - door/hood/trunk trigger if (-)
pin 30 - ground
pin 87 - to phone trigger

If the siren is a (-) out then you'll have to move some wires around. This might work though

Good Luck

p.s. one relay per trigger. You might have to put diodes on the triggers too.

Xetrems- thanks for your reply...I want the circuit to trigger after for indicator flashes due to the alarm flashes the indicators once on arming, twice on disarm, four times on prewarn and lots more when fully active.

Floaterr-ta for your input! Yea, I had thought of that, but I have lots of sensors that each would need to have a relay- one microwave, one shock sensor, one glass break detector, one tilt sensor, doors, boot, bonnent and an 'unauthorized' unlock trigger. This would lead to 7 additional relays to my already many extra bits.

I'll use this method if no appropiate circuit is posible.

Anyone else?

Ok last suggestion ;)

Something like this

Since this uses little current you can hook the power of this straight to the siren output or relay the siren output to power this unit. Set the timer for 10-15 seconds. If the siren chirps on prewarn or arm/disarm the unit will not be powered up long enough to trip it's internal relay. When the alm goes full alarm the timer will be power unit the entire alm cycle (60-90seconds?)ends. Then the timer will have had enough time to reah zero and trigger the relay that could then activate your phone.

p.s. the little flip switch should just be shorted and the little push button switch probably sends a (-) to the chip. This might be able to be connected straight to the ground wire on the circuit board. Once again setting it up to start counting down as soon as it is powered up.

Good luck.

Use the TR-7. It can take a number of pulses before it will give an output.



-------------
Karl

Pacific Accessory Corporation
Mobile Audio Interfacing Equipment
Connecting You to Your Music Since 1976

you could just use a binary counter, easiest way is to use a 4 bit counter to count, at 8 (1000), trigger a monostable for the required time needed, it will reset itself and all...

Hi Karl,

whats the TR-7 ?

Glynn

oh yea,
I've come up with a diagram...will scan it and try to upload it tomorrow..your thoughts and opinions would be appreciated

Please correct me if I'm wrong, but this diagram should give me a triggered output only when full activation- due to 'full trigger' triggers used with 'ground when armed'.


Plus the output is ground output via a relay, so no 200mA maximum current loads either.

Cheers,
Glynn