Current and Voltage Limiter

Discussion in 'General Electronics Chat' started by Davidred15, Feb 23, 2015.

  1. Davidred15

    Thread Starter New Member

    Feb 23, 2015
    Hi guys,

    I'm been trying to figure out a proper way to design this circuit. I looked around on the internet couldn't find much help.

    I am trying to charge 8 12V SLA battery with a 13.5V @ 500W DC/DC converter. So potentially these battery could draw 40 amps. I'm trying to have Arduino connected to the batteries, however I can't find a good way to protect the electronics.

    I have looked for current and voltage limiter ICs but they don't include max input current. I don't know if they are capable of limiting 13.5v at 40 amp.

  2. AnalogKid

    Distinguished Member

    Aug 1, 2013
    If you are talking about charging eight separate 12V batteries at the same time from a single power source, I suggest tat you break your project down into eight individual chargers. Batteries that are supposed to be identical *never* charge or discharge at the same rate. SLA batteries are the easiest to charge and most difficult to screw up, but at these power levels you don't want the full 40 A available to any individual battery if it is supposed to see only 5 A. Linear Technology and TI have switched mode and linear SLA battery charger ICs. These almost always have a current monitor feature to limit the output current. At these power levels you will have to add external pass transistors and heatsinks. If you can give us a schematic of your application with the the source, chargers, and batteries, you'll get better answers.