Hello,
I was just wondering if anyone might be so kind as to check my 5V power supply circuit made with easyEDA.
Thanks for any input,
TonyA
It will not work properly. Your input is backwards possibly burning out your reverse battery diode. The center pin is generally positive. Also your regulator needs high frequency bypass capacitors which are missing. I would suggest you look at the data sheet published by the 7805 for the appropriate values etc. Not all are the same.
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You beat me to it 
For the OP....
Larger capacitors: Aluminum normally > 10 µf are good for storing energy allowing the circuit to survive large spikes in voltage. However they are very poor at squelching high frequency spikes and RF noise in the 10 Mhz and above.
Smaller Capacitors: Ceramic 0.01µf through 0.1µf and in some cases up to 1.0 µf are good for high frequency noise. The issue with the regulator is they could oscillate at very high frequencies. That is why the recommended value is in the lower range.
I see... Thank you for the input, sincerely appreciate it.
I'm planning to use this regulated 5V supply to power my project by connecting it to the 5V pin of an adafruit metro mini, which is like a small arduino uno.
You do realise they have their own on-board regulator, no need for external one.
I do know, but I have 12 pots, 2 MPR121 captouch boards, 1 I2C OLED display, and a CD74HC4067 MUX. I'm worried there's not enough amps to make all work when not connected to the PC for power via USB.
I've read about some people using the USB connector wired to a power barrel jack, but if using this method, would it still need to be regulated? (I know the usb input power goes through on onboard 5V power reg.)
Confused, and trying to think ahead. Thanks for any help.
TonyA
Or, maybe do the above schematic however regulated +5V into Vin of board, and power my peripherals with the 5V output pin of the arduino board?
No need really as the details of the on board regulator are freely available and rated as 1 amp max.
Add up your periferals and see......
Even then, each pin should not go over 20mA.
Rule #1 a power supply the Arduino is NOT!
Looking at the data sheet for the Adafruit Metro Mini this is on the first page:" * 5V onboard regulator with 150mA out, 3.3V 50mA available via FTDI chip. My advice is to use as your guideline as they guarantee the product only to these levels. Checking the drawing I found it is a MIC2255 5.0 Regulator. The first line of the data sheet states: "The MIC5225 is a 150mA highly accurate, low dropout regulator with high input voltage and ultra-low ground current." There is no way you will reliably get 1 amp.
Thanks very much for pointing that out. I have been reading about the onboard voltage regulator connected to the USB and the +V pin. I will take heed.
Hi,
What is your input supply voltage to the 5V reg.
Do some calculations to see how much power you will dissipate in the regulator at your estimated load current of 1A.
You may or, and I would guess, you will need a heatsink on the regulator.
Tom... 
I'm not sure yet, but probably 7-12V. Will look into this and the heat sink. Thank you for reminding me about that.
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