Hi
I have a car alarm which does not come with a separate battery back-up siren (in case thief disconnect car main battery), I power the siren (hidden)with a separate Sealed Led Acid Battery (little 12V 1.3AH), as the siren is triggered wirelessly using FM signal, it drains the battery quite quickly, so I need to have the battery topped up all the time, I cannot connect directly to the cigarette lighter as it may overcharge and overcurrent during crank up.
Anyone has a circuit that can charge up this little 12V 1.3AH battery with overcurrent protection and overcharging protection? Much appreciated.
(if anyone interested in wireless 2 way car alarm with no wiring (won't void warranty of new car try carscop DIY alarm see ÎÞ±êÌâÎĵµ, works pretty well for me)
I have a car alarm which does not come with a separate battery back-up siren (in case thief disconnect car main battery), I power the siren (hidden)with a separate Sealed Led Acid Battery (little 12V 1.3AH), as the siren is triggered wirelessly using FM signal, it drains the battery quite quickly, so I need to have the battery topped up all the time, I cannot connect directly to the cigarette lighter as it may overcharge and overcurrent during crank up.
Anyone has a circuit that can charge up this little 12V 1.3AH battery with overcurrent protection and overcharging protection? Much appreciated.
(if anyone interested in wireless 2 way car alarm with no wiring (won't void warranty of new car try carscop DIY alarm see ÎÞ±êÌâÎĵµ, works pretty well for me)