A couple of power supply questions

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1

If I have a 2.3 to 2.4A total circuit load will a 2.5A wall adapter power supply be sufficient, or is that running it too close to capacity and I should use a 3A one?

Also as I google around I see some schematics with larger (100uF - 4700uF) bypass capacitors near the power socket, and some with none...I know about placing 0.1uF decoupling caps near the ICs, but how do you know if you need a bigger bypass capacitor, and what value to use? If it matters, I'm using a regulated switching supply.

Thanks as always.

2

I would go for the 3A one as it will run cooler and so last longer in this application.

You use large caps when there is a large current transients. For example if you are driving a stepping motor with a chopping regulator there is a large ripple current you need big caps. Where as if you are running a high power LED with a steady current there is no need for large caps.

3

Thank you!