As main goals, I have two things in mind:

• Generating a control PWM signal from a PID controller.
• Add a Night Light Control.

Applications: “Night Light Control” in our home, business or even on public roads or “Street Light Control”. It can also be used to charge 3V, 5V and 12V batteries.

STM32F407G-DISC1 Configuration

STM32F407VG board

• STM32F407VGT6 microcontroller featuring 32-bit ARM® Cortex®-M4 with FPU core, 1-Mbyte Flash memory, 192-Kbyte RAM in an LQFP100 package
• On-board ST-LINK/V2 on STM32F4DISCOVERY or ST-LINK/V2-A on STM32F407G-DISC1
• USB ST-LINK with re-enumeration capability and three different interfaces: Debug port, Virtual Com port, and Mass storage.
• Board power supply: through USB bus or from an external 5 V supply voltage
• External application power supply: 3 V and 5 V
• LIS302DL or LIS3DSH ST MEMS 3-axis accelerometer
• MP45DT02 ST-MEMS audio sensor omni-directional digital microphone
• CS43L22 audio DAC with integrated class D speaker driver
• Eight LEDs
• Two push-buttons (user and reset)

As we can see in the schematic diagram, this system mainly performs two functions: first it´s dedicated to charge the battery, and once fully charged, then turn on or off a lamp by means of a LDR light sensor, if it´s at night turn on the lamp and if it´s daylight, turn it off.