ESP8266 portable WIFI killer minimal system version 2-in-1 power supply

System introduction:
The system is 5.78*4cm in size. It is divided into upper and lower layers. The upper layer is the smallest system board, and the lower layer is the bottom board, which is used for fixed batteries.
√Onboard USB to serial port and automatic download circuit do not require cold start
√USB power supply or lithium battery power supply, slide switch to select the power supply mode, LED indication of different colors
√With lithium battery voltage detection circuit, 0.248:1 voltage division, maximum support 4.03 V voltage detection (ESP8266 ADC supports 0-1.0V voltage)
√ All IO ports and power supplies are lead out, and can be used as a development board
√ The attachments include WIFI killer firmware with OLED display and ESP8 burning software
 
system functions
1. Use lithium battery The power supply method is as shown in the figure below. Select the slide switch to the BAT position and the red indicator light will be on.
2. Use the USB port to supply power or download the program as shown in the figure below. At this time, slide the switch to the USB position, and the yellow indicator light is on:
3. Use the TP4056 module to charge the lithium battery (1-2 yuan on a certain product):
4. Use the USB port to provide power or download the program as shown in the figure below. At this time, slide the switch to the USB position and the yellow indicator light is on:
 
when used as a WIFI killer, you can directly download the firmware in the attachment and run it. It can be used to block or copy 2.4G WIFI. Attached below is a copy of the rendering named "7-2" WIFI:
Summary:
This module can also be used as an ESP8266 minimum system board. All available IO ports and power supplies are led out with pin headers and can be directly connected with DuPont cables.
When using lithium batteries for power supply, in order to prevent the lithium batteries from being punctured by the welded in-line components, a base plate of the same size is made. Copper pillars can be used to connect the system board and the base plate, and the battery can be glued to the base plate. See the schematic and PCB below