Heating station ESP32-C3-12F

The project is based on the IoT heating platform project 8266 of Qifan Technology and ported to ESP32C3: https://oshwhub.com/dhx233/pcb-heng-wen-jia-re-tai;
Modification
1) Based on the open source heating platform code of Qifan Technology, there are many problems in the compilation, so some functions are also disabled.
2) Modify the DC to DC power input, the small platform is low power enough and safe.
3) Change to C3. Why use C3 instead of 8266? There is only one reason, saving the serial port IC makes the circuit simpler.
4) The code mainly modifies the NTC temperature detection algorithm. The average temperature is no longer jumping after multiple sampling.
5) In terms of NTC circuit, the maximum sampling voltage of C3 is only 2.77V. Therefore, the ordinary pull-up will directly exceed the voltage. Therefore, a 20K resistor is connected in parallel, and even if the temperature is relatively low, it will not exceed 2.77V within the ADC range. IC sampling temperature is not used because IC is too expensive.
6) Temporarily removed the lighting IoT (the IC was unstable at first and the wifi could not be turned on), you can add it later.
7) Automatic cooling function, when the temperature is higher than 50 degrees, the low-speed fan will be turned on, and when the heating is turned off, the maximum wind speed will be automatically turned on, and the fan will be automatically turned off when it is lower than 50 degrees.
8) Added a buzzer, but the code has not been added.
 
I am also just a newbie. I have made 2 versions before this version. At the beginning, I used C3 to directly paste the IC. Due to lack of experience, the operation was unstable. So the third version still uses modules. Besides, the IC package is very unfriendly to beginners. It is basically impossible to solder without a heating table. It is now a chicken or egg problem.
 
I will try to use IC later.
Later, I will also try to add current power supply in the improvement. Based on limited knowledge, I hope that some friends can give reference to this circuit.
 
Video address: https://www.bilibili.com/video/BV1u84y1x7to/?share_source=copy_web&vd_source=ecd4e13cdad2e5a0581455b3731fb13cFeatures
 
:
Two rolls of finished products. Free for a single month.
The small bed has high power and heats up very quickly.
Try to reuse parts to reduce the cost of purchasing different parts.
Support 24V 5.5DC power supply and PD20V fast charging. (12V can also heat up slowly with only 40W power, and the highest temperature is about 180 degrees)
The power supply heating and program board are separated, and the extra control board can also be used as a normal development board.
Everyone is attracted by the appearance, so I won’t say much about the biggest advantage.
 
Disadvantages:
Based on the ADC itself, the temperature is inaccurate. The equipment on hand is limited, and after ordinary infrared temperature measurement, the temperature is close. The tin bar and solder paste are also melting at close temperatures. If you have high requirements for temperature accuracy, please use IC temperature sampling.
NTC is soldered on an aluminum substrate. The temperature rise will increase the wiring resistance, so it will also affect the sampling accuracy. If you mind, you can choose not to use an aluminum substrate.
(Considering the plastic shell, it is recommended to use below 250)
 
 
NTC calculation formula:
(Formula unit: voltage mV, resistance r, temperature C)
Correction coefficient = maximum measured voltage (2770) / measured voltage * intensity (0.052) + 1; // Reduce the intensity when the measured temperature is higher than the displayed temperature. Total resistance = measured voltage / pull-up resistor voltage (3300) * pull-up resistor (5100) / (1- measured voltage / pull-up resistor voltage); NTC resistance = pull-down resistor (20K) * total resistance / (pull-down resistor (20000) - total resistance) * correction coefficient; Temperature = 1 / (log(NTC resistance / nominal resistance (100K)) / B straight (3950) + 1 / (nominal temperature (25) + 273.15)) - 273.15; //Native NTC calculation formula. When
 
purchasing parts, please note
that EC11 should be purchased with a patch height of about 10MM. A handle that is too long will affect the appearance.
The buzzer uses 9MM.
 
Installation hardware configuration
M3*10-cross countersunk screws*20 (because the head is thinner than the hexagon socket, the four corners will not bulge) M3*14+6 copper*8 (connecting the main control to the middle insulation board) M3 injection molded copper nuts (copper nuts look better, ordinary nuts are also OK)
6*4*4 copper sleeves*4 (for bed and PCB conductors) 4*3 high temperature resistant PTFE tubes (used to isolate copper sleeves and screws)
TM441 high temperature resistant silicone (seal the NTC on the heating plate)
The file fully shares all source files, which is convenient for everyone to transplant and develop.
 
Installation Note:
The file fully shares all source files, which is convenient for everyone to transplant and develop.
Do not solder the oled screen to the board, just stick it in. It is convenient to adjust the height and shell matching.
Shell sharing address: https://www.tinkercad.com/things/8NImeO9GUDP
 
 
[Tencent Document] Heating platform installation instructions https://docs.qq.com/slide/DSmNHSHpObmdiTFhh
[Tencent Document] Heating platform complete BOM https://docs.qq.com/sheet/DSkJDSkZXeWFwS3l6
 
Sharing exchange QQ group: 853563090