Hi Dr. I'm using the UC3906 to manage the gell battery Im using in the alarm system I mentioned a few weeks back. Im running few tests before I have the final ( I hope) proto pcb made.
I ran the unit until the 12V gell cell was just about dead flat. I then plugged in the external power supply but the battery charging system based on the UC3906 didn't kick in.
I ripped off the design from the kit based on the UC3906 sold by Altronics. I think it was based on a sil chip article. I remember you said you had used the part in your projects.
Is there any reason the IC wont charge a dead flat battery? Ive looked through the TI data sheet and cant see any indication that it wont charge a dead flat battery.
Once I realised the circuit wouldnt charge the gel cell I connected it up to my bench top power supply and the gell cell took a charge no problem.
Whats your diagnosis Dr.?
I ran the unit until the 12V gell cell was just about dead flat. I then plugged in the external power supply but the battery charging system based on the UC3906 didn't kick in.
I ripped off the design from the kit based on the UC3906 sold by Altronics. I think it was based on a sil chip article. I remember you said you had used the part in your projects.
Is there any reason the IC wont charge a dead flat battery? Ive looked through the TI data sheet and cant see any indication that it wont charge a dead flat battery.
Once I realised the circuit wouldnt charge the gel cell I connected it up to my bench top power supply and the gell cell took a charge no problem.
Whats your diagnosis Dr.?