Little before my PC goes kaputt, Raj from Embedded Lab sent me an email with his latest project, that unfortunately i could not post all this time. Raj made a real-time monitoring system for the car battery, based no the PIC 16F1827:
|My 2010 Equinox has got every feature that a modern automobile should have. However, one thing that I personally find missing is the real-time monitoring of voltage across the carís 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. This project is about making a simple electronic voltage monitor system for carís battery and its charging system. It plugs into the carís 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. Microchipís 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.|
You can find complete documentation here. Thanks [Raj]!