Measure. - In here we will show you Circuit Schematic and Project Robot Battery Meter using IC LM3914. Often, simple robotics projects are powered from a small power bank consists of common dry cells (1.5Vx4=6V) or Lithium-Polymer cells (2S LiPo=7.2V). Ofcourse, the 5V required for the microcontroller and related circuits is derived from this input supply using a low-drop linear fixed voltage regulator like LM1117-5. Here is a simple yet useful circuit of a Robot Battery Meter, capable of displaying the battery voltage level in a clearly-visible 10-LED Bargraph display. After successful construction, you can attach this module to your existing robotic project without any difficulty.
The circuit is based on the renowned LM3914 IC from National Semiconductors (NSC). The LM3914 is a monolithic integrated circuit that senses analog voltage levels and drives 10 LEDs, providing a linear analog display.