ESP8266 spot welding machine 2.0

The BOM parameters are subject to the schematic diagram. The programs and libraries are in the attachment.

The entire spot welding machine is divided into power board, control board and bottom protection board. The solution of external power supply  

Power board: consists of 6 (40V300A) high-power MOS connected in parallel to form a PCB with large-area windows and buried M3 copper pillars to meet the requirements of high-current circuits

Control board: The power supply uses a step-up and step-down or step-down and step-down scheme to meet the voltage requirements of wide-voltage operation. 

              MOS is driven by TC4427 dedicated driver chip 

              The display part uses a 0.42 LED display to display the power supply voltage mode, welding time, delay time and other parameters.

              A simple program was developed using the Arduino IDE. There may be a problem with the time parameters when the computer is turned on for the first time because the parameters are not set and the previously unknown data is read.

Maximum voltage range: 3.7V-16V 12V-30V         

Since there is no suitable power supply and other accessories, the project has not had the opportunity to be tested, so it has been held up until now.

Disadvantage: It cannot be powered by 2.7V supercapacitor because when the power supply voltage is less than 3.7V, the SX1308 (2--24V input voltage) boost chip does not work due to the diode voltage drop and excessive power consumption of the subsequent stage, resulting in abnormal voltage.

Problems that occurred during the functional test: (Due to the lack of high-power power supply) During spot welding, the power supply voltage fluctuated too much and the power was reset, causing the MOS to remain on.