Minimalist Arduino using ATMega328P microcontroller

Overview
Here at the Transistor, we love the Arduino platform, so we decided to make our own Arduino Clone. The Minimalist Arduino is designed for use in permanent or custom circuits on solderless breadboards, stripboard, or custom PCBs. It contains only the bare minimum parts required for building the Arduino platform. The schematic for the board can be downloaded here (pdf). Please read all instructions on this page before assembly. The parts list is as follows, with linked manufacturer datasheets when available:
These parts consist of two main components: The power supply circuit, and the ATMega328P and supporting circuitry. The power supply circuit is made of of the LM7805 voltage regulator, (2)10uF capacitors, (1) 150 Ohm resistor and (1) green 3mm LED. Circuit power can be supplied using these components and a 7 to 18V input voltage, or via a separate regulated voltage source such as power over a USB to Serial FTDI converter. Only use one power source to drive the 328P chip, or you may damage it.
The remainder of the components are part of the ATMega328P circuit and support. This includes (1) clock crystal, (2) 22pF capacitors, (1) 10 kOhm resistor, (1) 3mm Green LED, (1) 150 Ohm Resistor, and (1) 100nF capacitor. The kit contains no wires, jumpers, or reset switch as the applications of this kit are intended to be open-ended and we did not wish to include unnecessary components.

Communicating with the Minimalist Arduino
In order for this kit to be fully functional, you must have a means by which to program and communicate with it. We did not include any means to do this in the kit, though our schematic shows the two most common methods for programming or sommunicating with a standalone ATMega328P: A USB to Serial FTDI dongle, and an ICSP Programmer header pinout.
We recommend using the USB to Serial FTDI chip as the primary method of programming and communicating with the Minimalist Arduino in conjunction with the Arduino IDE. Note that the second 100nF capacitor is used on the reset line for this method. The USB to Serial FTDI converter you use may not require this capacitor to function properly. Be sure to check your documentation. There are many places which sell USB to Serial FTDI chips. We recommend the USB-BUB from Modern Device. They are also available from Sparkfun and probably many other locations which we have not used. Since this chip has a reset pin and will automatically reset the 328P when programming, there is no need to include a physical reset switch in this kit. Also, a single USB to Serial FTDI board will be able to program as many kits as you want, as long as continued serial communication with the board is not required.
 
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