LM2596 multi-channel DC-DC step-down circuit solution

This project is used to verify the solution verification board design of the DC-DC chip LM2596-12/5.0/3.3/ADJ (product number C95366/C17127/C116713/C10002/C7929/C29781, etc.) from Lichuang Mall.

The power solution board provides 12V, 5V, 3.3V fixed voltage and adjustable voltage output. The terminal blocks can use splicable terminal blocks with P=5.0mm or P=5.08mm. There are spring terminals in the BOM for easy installation. The whole page is 91.7mm*99.3mm, and you can use Jialichuang's five-yuan discount on board printing.

The power supply voltage of the power solution board needs to be more than 1.5V higher than the maximum output voltage, with a maximum of 40V (different manufacturers produce slightly different products). The maximum output current of a single chip is 3A. The voltage input on the board is connected to a fuse. The input is limited according to actual usage. current value.

In order to ensure the passage of large current and sufficient heat dissipation, the main circuit parts are all filled with large-area wiring. For manual welding, it is recommended to increase the temperature of the soldering iron or use a hot air gun for welding. Open holes on the back of the chip to the bottom layer and open windows to improve the heat dissipation effect. If the chip works at a higher power for a long time, please also attach a heat sink to the surface of the chip.

If the power is taken from the mains, it can be rectified and filtered through a power frequency transformer to obtain the DC36V input VIN. After conversion by the power board, it can be used as the power supply for the microcontroller and each module chip, but cannot be used as the DC input during DC-DC conversion.