What is it?

Our PIC18F/QFN28 board is designed to with different configurations. In this setup, we have assembled the board with a USB connector and power selection circuit. The board also has a 12mhz crystal to run the on board PIC18F24K50 at 48mhz (with 4x PLL enabled.)

And to go along with the USB, there is a Program button (attached to RB4), to allow you to enter program mode without extra hardware.

Features

• PIC18F24K50 (QFN28) Mounted on board
• 12mhz External Crystal Oscillator (for higher accuracy.)
• USB Mini-B Connector and Power Selection Circuit
• 2.1mm Barrel Jack for Power Input
• Linear Power Regulator (allowing input voltage 7.5v > Vin > 25v)
• Power output headers to connect to your breadboard or other boards.
• Bypass capacitors and filtering on power input, regulator, USB, and output to help with those stray electrons. :)
• Power LED Indicator.
• 3mm mounting holes, 4mm from board edges.

Why did you make it?

Because it is a very basic tool that we use in any microcontroller project. You always need the circuit to run the controller, and having it on a board and ready to program makes life a lot easier. It also makes the circuit very dependable and clean, as we added plenty of EMI filtering and protection.

What makes it special?

It has an automatic power selection circuit to choose between user supplied power (barrel jack/power in) and USB power. Due to the USB bus limitations, the circuit prefers user supplied power.

Also, if you use a barrel jack (wall wart) to supply power to the board, you can get that higher voltage on the Power In pins, as they are directly connected to the barrel jack.