9 Volt 2 Ampere DC Power Supply Circuit Diagram

Description

There is little to be said about this circuit. All the work is done by the regulator. The 7809 can deliver up to 2 amps continuous output whilst maintaining a low noise and very well regulated supply. The circuit will work without the extra components, but for reverse polarity protection a 1N5400 diode (D1) is provided at the input, extra smoothing being provided by C1. The output stage includes C2 for extra filtering, if powering a logic circuit than a 100nF (C3) capacitor is also desirable to remove any high frequency switching noise.

Circuit diagram:

Circuit diagram

Parts:

  • C1 = 100uF-25V electrolytic capacitor, at least 25V voltage rating
  • C2 = 10uF-25V electrolytic capacitor, at least 6-16V voltage rating
  • C3 = 100nF-63V ceramic or polyester capacitor
  • IC = 7809 Positive Voltage Regulator IC
  • D1 = 1N5400 Diode