I have studied that there is a transformer which steps down the ac voltage after then bridge rectifier to convert into ac to dc and then given to filter, this is what I have learnt in books, but when I open a mobile charger I couldn't figure it out how it actually works?
Electronic – How does a cell phone charger work?
power supply
Best Answer
Phone chargers are incorrectly named. Most are 5 V power supplies. The charge control is done inside the phone. The power supply will continue to give out 5 V when the phone is completely charged.
Figure 1. Switched-mode power-supply block diagram.
How it works:
Figure 2. Anatomy of an SMPS 'charger'. Image source: Analogic Tips.