Powering pic16pro40

[pearlyred]

Hi, could someone just clear this up for me please. I'm looking at creating the pic16pro40 by bojan dobaj from https://www.electro-tech-online.com/custompdfs/2005/09/p16pro40.pdf

I think I understand the lower schematic for the programmer. I just want to make sure I'm powering it correctly so i can go buy parts. If I just want to power it using 2 9v batteries, how would I create that and use it to power the programmer? Do i still need all the voltage regulators and such in the top schematic of that design?

It also mentions to use a ac/dc adapter and change the capacitor inside to 25V. I have an unregulated wal-wart that can output up to 12vdc and 500mA. Is this a better alternative?

Cheers
lee

 

[Nigel Goodwin]

Hi, could someone just clear this up for me please. I'm looking at creating the pic16pro40 by bojan dobaj from https://www.electro-tech-online.com/custompdfs/2005/09/p16pro40-1.pdf

I think I understand the lower schematic for the programmer. I just want to make sure I'm powering it correctly so i can go buy parts. If I just want to power it using 2 9v batteries, how would I create that and use it to power the programmer? Do i still need all the voltage regulators and such in the top schematic of that design?

Just use the circuit exactly as is, and feed it from two 9V batteries in series, I've used them for years like that! - you MUST have the regulators, you don't 'need' the bridge rectifier, but it does no harm, and means it doesn't matter which way you connect the supply.

It also mentions to use a ac/dc adapter and change the capacitor inside to 25V. I have an unregulated wal-wart that can output up to 12vdc and 500mA. Is this a better alternative?

They tend to be a bit hit and miss, depending on the regulator, as long as it's got a high enough output under the load, it will work fine - but you should be looking at not dropping below 16-17V on the input to the 13V regulator. If hum on the supply drops below that?, then the programmer won't work.

 

[pearlyred]

Thanks for that Nigel, I'm gonna go with the 9v batteries for now, dont wanna start messing with mains power when I dont understand it properly.

Just wanna check a few values on parts as I cant get the exact ones mentioned in the schedule.

The bridge recitifer, you said I can do without it, but i'd still prefer to put something in there. Closest I seem to be able to get is a 100V 1A one (1B4B42 DIL 1A). Is this suitable and does it effect any other parts? Is this recitifer basically doing what the 1N4004 diodes seem to do in other designs?

With the voltage regulators, 78L05 is cool, I can get that at 100mA. For the 78L08 though, closest I can get is 7808, which is the 1A version. If I understand correctly this shouldnt matter though, it just means it can regulate the voltage up to 1A current, is that right?

I think probably the most confusing part is the capacitors. There are just so many types and values for the damn things.

If I go with the Electrolytic RB I can get a 220uF at 50V.
For the 100nF (or 0.1uF) I'm a bit stuck on what to get. I can get a 'greencap' at 100vdc, a 50vdc monolithic, a 35v tantalum, or a 50v RBLL low leakage electrolytic. Dont really understand the differences with these, there are too many .

I think thats just about it.. All help is appreciated

Lee

 

[Nigel Goodwin]

Thanks for that Nigel, I'm gonna go with the 9v batteries for now, dont wanna start messing with mains power when I dont understand it properly.

Just wanna check a few values on parts as I cant get the exact ones mentioned in the schedule.

The bridge recitifer, you said I can do without it, but i'd still prefer to put something in there. Closest I seem to be able to get is a 100V 1A one (1B4B42 DIL 1A). Is this suitable and does it effect any other parts? Is this recitifer basically doing what the 1N4004 diodes seem to do in other designs?

Any 1A bridge will do, as long as you connect it the right way round!, four seperate diodes would be fine as well - it's in no way critical.

With the voltage regulators, 78L05 is cool, I can get that at 100mA. For the 78L08 though, closest I can get is 7808, which is the 1A version. If I understand correctly this shouldnt matter though, it just means it can regulate the voltage up to 1A current, is that right?

The 1A version should be fine, but as it takes hardly any current from the 13V rail it's a bit of overkill

I think probably the most confusing part is the capacitors. There are just so many types and values for the damn things.

If I go with the Electrolytic RB I can get a 220uF at 50V.
For the 100nF (or 0.1uF) I'm a bit stuck on what to get. I can get a 'greencap' at 100vdc, a 50vdc monolithic, a 35v tantalum, or a 50v RBLL low leakage electrolytic. Dont really understand the differences with these, there are too many .

The 0.1uF should be non-electrolytic, either of the first two would be fine.