1. Rectification

2. AC to DC Electricity distribution –Power stations –Transformers –Transmission lines AC Electronics DC –Smooth –Stable

3. Process of rectification Conversion of AC to DC Half-wave Full-wave Dedicated circuits –Contain diodes Semiconductor Thermionic –Power rating Supply current to circuits

4. Half-wave rectification Only the positive half- cycle of the AC supply is allowed to pass

5. Half-wave rectifier circuit Simple! Single diode ‘Load’ –DC circuit…not really getting DC! V ac Load

6. Full-wave rectification Positive AND negative half-cycles converted to ALL positive

7. V ac Load Full-wave rectifier circuit Bridge circuit Load –Circuit requiring DC

8. Bridge as two potential dividers V out V ac

9. Capacitative smoothing V out V ac

10. Smoothed output Un-smoothed –Large ripple voltage –Not true DC Low-value smoothing capacitor –R load C small High-value smoothing capacitor –R load C big

11. www.search for... Capacitors Rectification PSU Electronic power supplies Bridge rectifiers