Screwduino

Features

Arduino UNO Compatible (Arduino bootloader)
ICSP header for program download
Standard 6-pin FTDI connector
4-pin I2C connector
Reset switch
Other than power regulator only uses through-hole parts
5mm pitch screw terminal blocks
Four (4) 4-40 mounting holes with clearance for screw heads, standoffs and/or nuts
7-12V DC on standard 2.1mm DC power connector
Power selection jumper (FTDI, Regulator, Screw Terminals)

Gets away from all of the painful wire jumpers and pins that constantly come loose. Makes the step from prototype to final design much easier.

Method	Material Costs	Labor Tasks	Power/Ground pins	Wires secure?	Mounting	I2C Support
Processor	UNO - $30	Strip wires and solder to parts	3 GND1 PWR	Wires don't stay in holes with any stress.	Poor	No connector
Breadboards	Uno - $30 +Breadboard $10	Strip wires or use breadboard wires	120 each PWR/GND for 700 point breadboard	Moderately secure since the holes are usually “tight”	Poor	No connector
ProtoShields	Uno - $30 +Shields - $15	Lot of time- consuming soldering of custom wiring	Vary but usually enough although maybe not connectorized in the best use	Wires typically soldered so secure	Poor	No connector
Sensor Shields	Uno - $30 +Shields - $15	Use custom wires	Excellent at 1 per Arduino Digital/Analog pin	Connectors are secure	Poor	Yes
Screw Wings	Uno - $30 + Wing Shield - $15	Strip wires and solder to parts	Varies depending upon shield	Connections very secure	Poor	No connector
Screwduino	$30 (est)	Strip wires and solder to parts	5 – Ground 4 – PowerAdditional on other connectors	Connections very secure	Excellent	Yes

[ Screwduino Schematic]

Measured 15 mA with 9V external power input (no loads but running program).

This jumper selects the power source for the card
- Install jumper across the USB pins to power the card from the FTDI interface.
- Install jumper across the EXT pins to power the card from the DC jack.
- Leave the jumper off when powering the card from the ISP connector.