So many types of Car USB chargers are available which step down the 12 volt DC from the Car battery to 5V DC for charging devices like Mobile phone, Tablets, MP3 player etc. These are usually connected to the Lighter socket to get 12V. The low cost chargers do not have a circuit inside but simply providing 12V DC directly. Only a fuse is present in it. This is dangerous because, the Car battery is a high current one which can damage the gadgets. Here is a simple solution for this. We can make a Voltage and Current regulated Car Charger using the IC MC 34063. It is a Step down DC – DC Converter IC with many features. The output from the circuit will be 5 V at 500 mA.
Most of the low cost LED Emergency lamps do not have LED indicators to show charging and load on conditions. This simple circuit solves the problem. It can be hooked in the Emergency lamp. A Green LED lights when the charging is going on and turns off when the charger is disconnected or power fails. It gives a good indication that current is flowing to the battery. A Red LED lights when the load turns on. It also indicates that charging process stopped.
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