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.
MC 34063 is a Monolithic Step-Up / Step-Down switching regulator containing primary function for DC-DC conversion. It consist of an internal temperature compensated reference, comparator, controlled duty cycle oscillator with an active current limit circuit, driver and high current output switch. It operates from 3.0 V to 40 V Input and out puts 1.5 Amps current. Output voltage from the IC can be controlled through the Preset arrangement. It can be used to make a simple DC-DC converter but here a good circuit is given.
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