12V battery level indicator circuit using LM3914
In this 12V battery level indicator circuit, LM3914 is the main component which from national semiconductors. The IC Lm3914 which can operate a wide supply voltage from 3V to 25V DC. The LM3914 can drive voltage levels and display of 10 LEDs in dot mode or bar mode. The brightness of the LEDs can be programmed using an external resistor. The LED outputs of LM3914 are TTL and CMOS compatible.
LM3914 Battery Level Indicator Circuit Diagram
Cascading two LM3914.
Two or more LM3914 ICs can be cascaded together to get an extended display. The schematic of two LM3914 ICs cascaded together to get a 20 LED voltage level indicator