Some modern cars do have this feature integrated, but most of us could use a real-time monitoring of voltage
across the car’s battery terminals. This may not seem to be that important but one of the most common reasons
for a car battery failure is the faulty charging system. If the charging system is not working properly,
the battery will not get the proper charging voltage (about 13.8 V for 12V battery)
across its terminals and it could go flat.
New Embedded Lab project is about making a simple electronic voltage monitor system
for car’s battery and its charging system. It plugs into the car’s cigarette lighter receptacle
and displays the instantaneous output voltage across the battery terminals on a
4-digit seven segment LED display. This helps you to get early warnings for possible battery
and its charging system problems. Microchip’s PIC16F1827 is the main controller in this project,
which uses the built-in Fixed Reference Voltage (FVR) module
to achieve a very precise and accurate A/D conversion of the battery voltage.
Simple, but well organized source code written in mikroC PRO for PIC
is also available on this Embedded Lab's blog.
