linear voltage regulator

[grekson]

I am building simple PIC based PCB and I need proper power supply for it.
Can I use L78M05CV 500mA, 5V votage regulator?
Can I connect this IC like below schematics from datasheet shows?
Do I need any additional capacitors...?
**broken link removed**

 

[Willbe]

Do I need any additional capacitors...?
**broken link removed**

That depends on if Vi is unsmoothed DC.

 

[crutschow]

To answer your question we need more info. What is your source voltage (Vi) and where is it coming from?

 

[grekson]

To answer your question we need more info. What is your source voltage (Vi) and where is it coming from?

Car's 12V battery power source. Don't know how smooth this is?

 

[Willbe]

Car's 12V battery power source. Don't know how smooth this is?

Without the engine running, extremely smooth.

 

[grekson]

Without the engine running, extremely smooth.

What about when starting the engine and turning on the hid lights?
Can these large consumers make any harmfull spikes for my MCU?
Do I need any additional electrolytic capacitor?

 

[Willbe]

What about when starting the engine and turning on the hid lights?
Can these large consumers make any harmfull spikes for my MCU?
Do I need any additional electrolytic capacitor?

Vehicle power can be very "dirty".

National Semiconductor makes/made ICs that interface with vehicle electrical systems, and in their application notes (somewhere online) they had a schematic for a workable transient suppression network.

You also might want to Google
"load dump transient"

The first thing I'd do is put a 1A, >600 PIV diode in series with the input of your regulator.

 

[Oznog]

The necessary capacitance will change with 5v regs. If you look that circuit up, and find a similar-looking 5v reg at Radio Shack or whatever, it may require a very different capacitance.