This is what the framework of the solar air detection device frame is. I've divided 3 parts, 1. The control of solar charge, voltage, and current. First, the light intensity sampling, and then to the voltage sampling, so that you can know the battery voltage, and the current light intensity of the approximate situation, and then according to this data processing, such as: the current battery voltage is full, the intensity is very large, then you can control the floating charge. If the charge is turned off at night. This is controlled by the program. If the battery voltage is low, then the light is strong and then a strong charge. Probably the idea is this (encounter difficulties) First circuit diagram design, I used an ad Buck PWM control, control the current voltage, solar panel voltage and current (light intensity measurement) control good access to the battery, add diode anti-reflux. After the ad Buck module down to 7V again 7805 This is OK, I design may be very bad, I feel the electricity a bit Fermat. Technology is not good. The battery voltage is measured by means of a resistor divider. The voltage charged by the PWM control is somewhat difficult to measure. 2. Air detection control for air detection, I used the stm32 RTC clock, air detection without real-time, because the power consumption is a bit large, and then set different time periods for detection, these are easier to read data, and then alarm, you can start with a button. LED prompt is activated. Record 30 times PM2.5. (difficult) in the RTC clock is a bit of a problem, general that spare clock General board is not good, hey, cause the problem here I do not know, later with the clock, 72MHz, Direct division can be divided into 1 seconds. There are 30 seconds to use when using the PM2.5 module, and then I started to think that I could not set 30 seconds, want to use RTC, and then want to know that 30 seconds. Timing 30 seconds, go in and wait, then measure the low-level time, and then calculate the concentration. Concentration calculation a bit of a problem, may PM2.5 a bit of a problem, there may be no test. 3. Display 12864, using this, shows the time, current voltage, light intensity, PM2.5 value, toxic gas level. You can also use the key to control the display of the PM2.5 value 30 times. This is used by someone else's program. (difficult) 5v LCD screen Then use a pull-up resistor, and then the IO port can be used to accommodate 5v feet. Specific point circuit diagram and program can not come out, because it sucks. It's really bad.
Solar Air Detection ideas
