Arduino boards only have headers that are convenient for shields and wire jumpers to connect to breadboard. But sometimes you just need a fast way to connect to some sort of component which is in SMT package. SARduino (Space-Age-Robotics-duino) was built with this in mind. Firs of all it is not and Arduino shaped, so it won’t fit shields. But it has bit prototyping area where components can be soldered directly on board. And this is not only for through hole, but also for SMT parts.

There can be various devices soldered like SOIC-16, SOT23-6, SC-70-6. This is really nice solution for prototyping and even for end design if you wish.

Standard Arduino comes with Atmega328 chip. It isn’t the top notch microcontroller when speaking of number of I/Os or Flash memory. You could go with mega version when real power is needed. But fact is that mega might be too much or simply too expensive. In that case consider Sanguino. It is an Atmega644 based Arduino board assembled on custom board and its cost in parts is about $8.

Atmega644 has more pins and twice Flash memory than Atmega328. The schematic was originally copied from real sanguino so only a soldering has to be done. There is a full support for Sanguino – all you have is to copy some files that makes it available. If you need more power and still need DIP packages Sanguino is right choice.

Arduino platform is great in its simplicity and tools out of box. When you need to interface something to Arduino board you can use shields or prototype on breadboard. Some hobbyists just go different way – they use AVR chip with Arduino bootloader and make custom PCB with desired features. Check out new Arduino development board that seems really attractive.

It is based on ATMega1284 microcontroller featuring 16K of RAM, 4K EEPROM and 128K flash. There are plenty popular peripherals already on board. These include Real Time Clock DS1307 with backup lithium battery. SD card socket, RS232 driver, FTDI FT232RL USB driver, JTAG header. And more handy stuff.

When a development board can be called Arduino? Obviously main reason is an Arduino compatible microcontroller and a bootloader that can be accessed from Arduino IDE. If you aren’t planning of using standard shields that need special layout, you can build Arduino board what ever shape and size you want.

Following Femtoduino project uses an Atmega328p microcontroller in QFN32 package, and 0402 size passive components. Due to small components and minimal circuitry, this arduino can fit on your fingertip literally (20.7×15.2mm). It uses 0.05″ connectors that can be braked out into regular 0.1”. Use this layout where circuit size really matters. BTW project is designed using Kicad.