Hi Basel,

It depends. What type of battery are you wanting to charge? Please provide the chemistry and the cell and battery pack voltages.

Hi Eric,

12V SLA battery pack.

Thank you

Hi Basel,

To implement a 12 V SLA battery charger, you have two routes.
1) Use a dedicated multi-stage charger IC such as BQ24650 www.ti.com/.../bq24650.pdf
2) Design a discrete charger circuit, which will be more difficult.

3 terminal regulators, such as the LM338 and LM1086, regulate the Vadj voltage across the upper voltage divider resistor R1 or Rs + R1 in the battery charger examples below. This is different from more recent linear regulators that regulate the Vref or Vfb voltage across the lower voltage divider resistor R2. The following examples' equations will not apply to the LM2941C.

Examples of 12 V discrete battery charger circuit for 3 terminal linear regulator is shown:
LM338 datasheet Figure 41 simple charger: www.ti.com/.../lm338.pdf
LM338 datasheet Figure 34 shows a more complex charger circuit.

More detail on simple charger circuit:
LM1086 datasheet Figure 21: www.ti.com/.../lm1086.pdf

Hi Basel,

If you want to charge your 12 V SLA battery at a fixed voltage, you could set your LM2941C Vout to 13.6 V. Charge time will be greatly increased compared to a multi-stage charger, but the circuit is much simpler. The SLA battery cannot be connected to the charger indefinitely at 13.6 V, as damage will occur to the battery. Constant voltage or constant current charging can impact battery life.