Power supply for PIC16F877A

I've the 24V DC @ 5A SMPS. I want to use it to power PIC16F877A micro

https://www.electronicscomp.com/g31...XLa4Wt3Dzdt5nBJJy2__e8ZN_dUjVgJBoCIfoQAvD_BwE

Which regulator IC I need to convert 24V DC into 5V DC ? Can I use 7805 ?
Input current is 5 A What's the safe input current for PIC16F877A ?

You could use a 7805.
It would not be very efficient using an analog regulator, but not a problem powering only a PIC as the current needed is very low,

The PIC itself could take anything from 2mA to 15mA, plus the load on the output pins and anything else running on the 5V supply.

The supply available current does not matter (other than being enough for the job), the load will only take what it needs.

rjenkinsgb said:

You could use a 7805. It would not be very efficient using an analog regulator,

Click to expand...

What's the efficient way ?

rjenkinsgb said:

The PIC itself could take anything from 2mA to 15mA, plus the load on the output pins and anything else running on the 5V supply..

Click to expand...

SMPS rated 24V DC @ 5A SMPS. It can deliver a maximum 5 A.

7805 can deliver 1.5 A but pic need between from 2mA to 15mA

Can pins of micro damage by maximum output 1.5A current ?

jab99407 said:

7805 can deliver 1.5 A but pic need between from 2mA to 15mA

Click to expand...

Can is the key word. Loads only take the current then need, as long as the voltage is correct.
You house supply is probably rated from 100 to 200A, but eg. a 10W lamp draws a fraction of an amp.
Likewise things in a car, running from a battery that can supply eg. 600A or more.

Having the correct voltage and adequate current available is all that matters.


A more efficient way would be a small buck regulator module; they are very cheap and very efficient.

At eg. 100mA, the 7805 on a 24V supply has 19V across it and would be dissipating 1.9W; it would need a heatsink.

A switching regulator (such as buck converter) "translates" power, with a small inefficiency.
The input current at 24V would be a bit over 1/5th of the output current.


Examples - this style is readily available from many suppliers:

Just be sure to adjust the output to 5V before connecting it to the 5V devices - the output voltage setting could be anything, as you receive them.