Popular Parts

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Another new page by russ_hensel, not much more than a stub now. Feel free to join in with your recommendations.


So many parts, so many variations, which to pick. Why not try to see what is popular:

Kits and Projects

If you're working from a kit or published project consider getting extras of the parts. The authors of these things tend to know, and pick, what's popular. If you use them once you may use them again; there are exceptions, though.

If you are working with X then Y where Y will help you find the popular parts

Note that links may or may not be to the best source. Look around, add a link if you find a better one. Do not delete a link, unless product is gone for good.


Because PICs are mostly digital logic, if you use PICs you will need most of the stuff in the Popular Parts#X=Digital Logic section as well as stuff in this section.

What Comment Specific Part

  • 16F877A
  • 18F2553 [1]
  • 18Fxxx

I don't recommend wasting time on pure programmers for development purposes. Once you get past the blinking LED stage, you are going to need a debugger.

  • RealICE - Mid to High End PICs
  • ICD2 - Broadest range
  • Pickit2 - Low to Mid range PICs

Proto Board

Some People hate them, but many find them a nice quick way to experiment. I have found a max clock speed of 4 megHz works well. Breadboard

see links


I keep 4 megHz and 20 meg Hz on hand. Note that some PICs can do without crystals, but timing is not very accurate. Check your spec. sheet, some PICs may be able to go to 40 meg Hz. Note that a couple of capacitors are needed as well. Ceramic resonators may be used instead.

  • 4 meg Hz
  • 20 meg Hz

Pull Up Resistors

Can be used as pull down as well. I use 10k ohms, often useful for other stuff as well.


Op Amp Need to condition your inputs? a op amp may be just the thing. See section on op amps.
LED How else can you say hello world? Pretty much anything will do. Do not forget to get a current limiting resistor 220 ohms or anything close. LED also come in arrays and as 7 segment displays for numerical read out.
  • 220 ohms
Push Button Need this for input. I get mine from salvage. Later I will find a source for you.
  • see links
Low Side Switch, Driver Chip When you need more power from an output port this is the way to get more than 10 times a much current, Not very expensive. One chip will drive 2 stepper motors. ULN2803 has 8 inputs and outputs. ULN2803
High Side Switch Driver Chip Like a low side switch, but on the high side. If you are driving "rows and columns" then you need some on the low side some on the high side. The UDN2981 has 8 inputs and outputs. UDN2981
Sensors There are so many, for light photo diodes and transistors, for temperature LM34 and similar see section on Sensors. *whatever
LCD Display Put out full alpha numeric data, several characters. Seems like a better? solution than LED when many characters are required. Probably best used with a controller to keep use reasonably simple. *HD44780 parallel interface

X=Op Amps

What Comment Specific Part
op amps consider ... what,
Proto Board Some People hate them, but many find them a nice quick way to experiment. ?
Resistors For precise gain you need 1 percent resistors. I start with 10k and use multiples and sub multiples.
  • 10k
  • 20k
  • 100K
trim pots When you need a bit of adjustability.
  • 10k
diodes When you need current one way, not the other. See Transistors, Diodes, etc. for details.
  • (FIXME: isn't this already too many? Trim.)
  • MBRA140 for Reverse Protection Diodes
  • 1N914 (300 mA DC forward; 75 V DC reverse)
  • 1N4148
  • 1N5711 Schottkey diode
  • 1N5817 Schottkey diode
  • BAT48 Schottkey diode
  • BAT85 Schottkey diode

Power Transistors An op amp might be good for 20 mA. Couple it to a darlington transistor and get a full ampere (1000 mA). You may want to go push pull with a pair of npn and pnp transistors. With this you can build power supplies, battery chargers, motor drivers, and audio amplifiers. TIPsomething
Sensors Measure something. See Sensors. Sensors

X=Digital Logic

If you use any microcontroller, you will probably also need most of the stuff in this section.

What Comment Specific Part

  • 74HC132 Quad 2-in Schmitt-trigger NAND gate


  • If you use a microcontroller in your project, the counters inside that microcontroller will probably be all the counters you need.
  • ?

Shift registers

Often used to expand the number of ports.

  • ?
  • 74HC595 -- for more output pins. SIPO eight bit shift register with output latch. Perfect for letting the propeller clock POV display slowly clock in the next value, then LOAD them all at once. Near the bottom of the page describing the "Digital Numeric LED Displays Tachometer (RPMs), Temperature, and Counter" project, David Cook says: "The 595 is a great 8-bit serial chip because data can be shifted in without affecting the existing output. All new data is then switched over at the same time. The 595 can also be daisy chained. In this case, 48 outputs are controlled with only three wires (data, clock, and latch)."
  • 74HC166 -- for more input pins. PISO 8-bit parallel-load shift registers.
  • 74HC165 -- for more input pins. PISO 8-bit parallel-load shift registers.

Voltage Regs Power to the Chips
  • LM7805

Voltage Reg

Easy choice is LM7805. A couple of caps usually go with it. .1 and .01 bypass caps are generally useful.

  • 7805
  • .1 uf
  • .01 uf

decoupling capacitors.

"I can only recall using less than 1uF decoupling cap in one circuit in the last 8 or so years ... 100nF bypass caps [0.1 uF bypass caps] are so 1990s. If someone tells you that should be the standard value, you should be careful about what other bad or outdated advice they may be dispensing." -- one post in the PICList Thread (EE) "1.0 uF Decoupling Cap - A Must?" by Olin

  • 1uF through-hole caps for solderless breadboard
  • 1uF 0805 ceramic caps for dead bug style prototyping and custom PCBs

X=electric motors

See motor driver for details.


"my favorite International Rectifier FU5505 power MOSFET transistor" -- David Cook