M128 CNC power supply G01

This project is open source hardware, and the software information can be found at https://www.yleee.com.cn/thread-89963-1-1.html.
 
The power supply design of this project is based on 20V5A. If other voltage and current are required, please modify the principle parameters by yourself. The specific location has been marked and explained.
There are basically no obvious problems after debugging. Compared with the previous version of the power supply, the biggest improvement is that the following method has been changed to make the power supply have no current bottom.
 
 
Structural dimensions: 100*130*150mm (width, height and length, length can be shortened to 130mm)
Power input method: external DC input
 
 
===========
Host computer support:
compatible with DPS series software of a certain board. This project does not spread or spread related software. If you need it, search and use it by yourself.
==========
The main control board integrates 3 types of LCD displays:
1. Shenzhen Anxin's store-black and white LCD screen ST7567 with backlight 18 feet. (mainly cheap 4 pieces and there are goods)
2. Simai micro LCD screen-12864-469 COG LCD display.
3. Shenzhen Lixian Electronics Co., Ltd.-12864b11.
Independent display board (recommended to use an independent display board):
1. Use Lao Wang's 2.8-inch screen, which has a good screen-to-body ratio. You can modify this board separately to replace the display.
The two high-priced screens are between 13-15, but they can be guaranteed not to be out of stock. Or you can modify the file yourself and add the LCD you have.
If you don't want to change the board, you can also open a separate display board and connect it through the FPC20P adapter of 12864b11. It is compatible with CC, CV display lights, onoffled and infrared reception, and can also be drawn on the new LCD board.
================
Transformer winding:
All use 0.15mm enameled wire. When winding, you can wind the primary and secondary in clockwise or counterclockwise according to personal habits.
The primary is 22 turns of two-wire 2 windings, which is exactly 2 layers. The actual circuit is 2 windings in parallel, or a single winding is also OK.
The secondary is 15 turns of two-wire 2 windings.
Pay attention to the same-name terminals.
The default voltage is determined by the input voltage and the number of turns, so it needs to be calculated. If other voltages are required, please fine-tune them yourself.
=================
Heat sink selection:
Because the voltage segment is divided into relatively fine sections, the maximum voltage difference is about 2.8V, which is the maximum voltage on the adjustment tube. Under the condition of 10A current output, the adjustment tube only generates a maximum of 30W of heat.
Therefore, the heat sink does not need to be very large. Of course, if there is enough space, the bigger the better.
 
Use the Ryzen AM4 heat sink. The thermal capacity is sufficient, and it is cheap at critical times. Basically, you can buy a set for less than 10 yuan, including the fan and can use it directly.
The actual measurement of 15W heat consumption did not reach 40°C in half a day. This structure seems to be suitable for load.
 
 
 
==============
Fan drive:
It is recommended to use high-speed optocouplers, which have simple circuits and no extra power consumption. (Recommended).
Ordinary low-speed optocouplers require additional circuits to increase the quiescent current by 20ma.
==============
DCDC module modification:
According to the calculation in the EXCEL table at the end of the article, the module is modified to a fixed minimum voltage output, such as 2V. Use the calculated upper and lower arm resistances to modify the module, and directly lead the FB interface to connect to the motherboard.
=============
DCDC replacement module KIC0210:
The solution defaults to 2V10A output, and is used with the M128 adjustable power supply. Replace the original KIC solution TPS40057. There is a howling sound when testing, which may be caused by the frequency being too low. Use with caution
 
=====================
 
 
 
 
The following is the transfer information:
M328V7 new feature list Support Atmega328P/Atmega644P/Atmega128/Atmega64 Support 12864 (LCD/OLED), Chinese and English interface Voltage and current curve display Built-in universal intelligent charger mode Built-in signal generator Built-in universal infrared decoder Support power-on default output voltage/default output off/use the last shutdown status Added running time display, scheduled power on/off/cycle power on Support no-load current deduction Multi-point calibration for better accuracy Maximum power protection, short circuit protection, temperature protection, automatic fan Separate ON/OFF button Support 8 groups of preset voltage and current Serial port control, compatible with the host computer of Ruideng CNC power supply Support control of the front-stage voltage following or winding switching Many other improvements