# How to convert 7V boost mode to 12V circuit?

First, connect two 7V/1A battery boards in parallel to get a 7V/2A battery board. The function of the two battery boards in parallel is that the power of the battery is higher and the current is higher, and the maximum current can reach 2A.

First, connect two 7V/1A battery boards in parallel to get a 7V/2A battery board. The function of the two battery boards in parallel is that the power of the battery is higher and the current is higher, and the maximum current can reach 2A.

Then it is 7V to 12V, but using booster chips, there are many types of DC booster chips, such as the commonly used LM2577, BT2013, BT2014, MC34063, etc.

Take MC34063 as an example below. MC34063 can be used for boost or buck voltage power conversion. The power input range is 2.5V~40V, the output voltage range is 1.25V~40V, and the output current is 1.5A. The output voltage formula is VOUT=1.25×( 1+R2/R1).

The principle is shown in the figure below: as long as the values ​​of resistors R1 and R2 are replaced, the output voltage can be changed. I choose R1=2.32K, R2=20K, and substitute it into the formula VOUT=1.25×(1+20/2.32)≈12V.

MC34063 circuit diagram

MC34063 module

Two battery boards are connected in series to form 14V/1A

There are many 14V to 12V circuits, you can also use the MC34063 circuit shown in the figure above, which can be used for both buck and boost. In fact, it is best to know the specific use of 12V in order to design a simple and effective circuit in a targeted manner.

If you want to design a 12V power supply to charge a 12V battery, there is no need to convert it. The 14V of two battery boards in series can be directly charged, and the battery is fully charged with a nominal voltage of about 1.15 times, so the 12V battery is fully charged with about 14V. , so use a 14V charger to fully charge the battery.