unregulated power adapter?

Table of Contents

How to select an unregulated power adapter
With the concepts above considered, selecting an unregulated AC to DC power adapter for your application can be summarized as follows:

• if you're replacing an existing power adapter:
  • choose an adapter matched as closely as possible to the original adapter's voltage and current specifications.
  • determine the required adapter DC output plug size and polarity. There are many possible sizes.
  • the DC output connector at the end of the cord can be changed or removed if necessary, but if you do this, the adapter can't be returned to the store.
• When choosing an unknown power adapter for your own application:
  • determine the power requirements (voltage and current needs) of your load device or circuit.
  • select a power adapter with a voltage and current rating that matches the load requirements as closely as possible.
  • the maximum current requirements of the load should not exceed the maximum current rating of the power adapter.
  • a power adapter that can provide more current than the load requires will sometimes work, but if the current difference is very large (say 30 to 50%) be aware that "ripple voltage" on the adapter output may be higher than ideal, and a filtering capacitor may be required to smooth out the DC output voltage of the adapter.
  • care should be take to ensure that the maximum input voltage of the load device is not exceeded.
  • determine the required adapter DC output plug size and polarity. There are many possible sizes.
  • the DC output connector at the end of the cord can be changed or removed if necessary, but if you do this, the adapter can't be returned to the store.