Improved version of ESP burning socket

There was a previous issue of an open source burning socket, and there were still a lot of people discussing it. It seems that there are still a lot of people playing ESP. I just changed a version later, so I shared it for everyone to use. Mainly because I am currently using it. It's more convenient to use, I hope everyone likes it.

For specific pin production, please see my previous issue: 

https://oshwhub.com/gnosis/esp-ji-tong-shao-lu-zuo

Or refer to the following open source projects

https://oshwhub.com/YAKE/esp_-ce-shi-ban_ver2

https://oshwhub.com/duyes/esp8266-shaolu-tiaoshi-jia

Thanks again to them too!

In this improved version, there are actually not many changes. The main changes are the following:

1. The automatic download circuit of CH340 reserves a crystal oscillator position and supports CH340C CH340B CH340G ( CH340G requires a crystal oscillator to work reliably, and others do not need it ). At present, when testing the download, it basically starts the download without delay and responds immediately. It feels very comfortable. ;

2. Add RX8025T clock chip, and Arduino can directly perform I2C communication debugging time (both ESP32 and ESP8266 can be used);

3. The SOP16 chip debugging bit is reserved to facilitate simple debugging of SOP 16 pins and below;

4. Reserve a complete external debugging interface (currently used more often for real machine debugging, mainly because it is particularly convenient^-^)

I have completely tested ESP32-WROOM and ESP-12F (ESP8266), and now everything is soldered to the board, so the external debugging port is mostly used for debugging.

There are several things to note about PCB:

1. If you use DRC inspection, you will find that the ESP8266 pad will report an error. After contacting EDA technology later, it is confirmed that there is no problem. It should be a software BUG, ​​and the actual board is used normally, so if you find that the DRC inspection has not passed, it does not matter. It’s okay not to conduct DRC inspection;

2. The original pinholes of the two burning sockets used will be relatively small. If no compensation is made during production, the ESP32 pin position test pin will not be inserted in. For this reason, I thought it was a problem with Lichuang's process. After complaining about this, we will communicate with you later. Only then did I realize that the original pins were too small. Now we don’t need to consider this issue when making boards, as they have all been enlarged.

External programming no longer only leads out a few like the previous version. Currently, all RX TX RTS DTR are lead out, and a 3.3V output is added, which can be powered when there is no external battery, so that even if it is external, it can be conveniently connected. It is automatically downloaded when burning. Let’s take a look at my current use:

For convenience, I welded two sets so that one set can be debugged directly and the other set can be tested.

See below is the ESP32 clock I am currently working on. It currently supports TF cards, temperature and humidity chips (only SHT30 and AHT20 are supported), and uses the RX8025T clock chip. I wrote the program myself. I have been testing it for a while, and the function is still good. Good, but I always feel that the sleep power consumption is still a bit high, more than 1mA. In this case, it is difficult for a 2000mAH device to work for a month (there are also power consumption when updating the weather and updating time. When testing at 240MHz, the current must reach 120mA , there is also 40-50mA at 80MHz), which is not consistent with the idea of ​​micro-power consumption.

Finally, let me talk about why we added the RX8025T clock chip. The main reason is that it supports low voltage. Although it seems to have been discontinued, it is very cheap to buy on TB. It has a built-in crystal oscillator and requires almost no external components. It is still highly recommended. I remember to buy it. It only costs about 6 cents, and it is very cheap and easy to use. Finally, I added several chip specifications in the appendix for easy reference.