Learning embedded designs with PIC

Discussion in 'Embedded Systems and Microcontrollers' started by a4wanman, Feb 16, 2012.

  1. a4wanman

    Thread Starter New Member

    Oct 24, 2010
    I apologize if this is not in the right forum.

    I'm just getting starting with PIC micros. I have some 8051 programming experience (C and assembly) from many years ago.

    I'm wanting to order some capacitors to get started. I'm OK on most items such as breadboard, resistors, LEDs, switches, etc. but not quite up on common caps used.

    What are some common capacitor types and values used in basic circuits for voltage regulators, oscillators, etc?

    For oscillators, I've seen circuit designs with 15 pf, 22 pf, 27 pf

    I guess smaller caps are OK to use ceramic discs, and larger to use aluminum electrolytics.

    Due to shipping costs, I would like to get a few caps to get started. The "kits" are currently out of budget.
  2. osx-addict


    Feb 9, 2012
    Dont forget that many semi-conductor places such as Microchip will be happy to send samples for free of charge to many people unless your outside the USA. I ordered a few samples two days ago.. Just a thought.. and I think you're in the right place.
  3. ErnieM

    AAC Fanatic!

    Apr 24, 2011
    For the moment you're going to need caps for power supply bypassing, and that isn't critical as far as value goes.

    You wouldn't go wrong if you just buy some ceramic 0.1 uF caps, which are going to be rated at least 25 volts (50 or 100 are also just fine). If you have some spare money also get some electrolytic caps rated perhaps 10uF at say 10 to 50 volts.

    I've seen values such as 15 pf, 22 pf, 27 pf in crystal oscillator circuits. Again, that value isn't very critical so if you are using crystals get a few 22 pF caps. You also have the option of using ceramic resonators, very similar to crystals, slightly less accurate, but they come with the caps built right in.

    Also, many PICs have an internal oscillator that works quite fine, and since it is less hardware it is one less thing to get wrong when beginning with these things.
  4. t06afre

    AAC Fanatic!

    May 11, 2009
    Get some 100nF and 10uF(tantalum) caps. If you use breadbord. A setup using crystal as oscillator may give you some problems now and then. In any case keep the crystal as clase as you can to the micro. If you use a PIC with internal oscillator you will have no problem at all. And you also free up two I/O pins :) I would not recommend using the PIC16f84. It is outdated. The newer ones cost less and have a lot of onboard funtions. Like several timers, PWM and UART to mention some