Breakout Boards

In addition to ICs and sensors mounted on breakout boards and larger mbed baseboards with several connectors, there is a wide array of individual breakout boards commercially available to connect external devices that require a connector. Most of the breakout boards come with holes spaced by .1" for the connections to the pins. You can solder break away header pins like those seen below into the .1" spaced holes after breaking off a strip with the required number of pins.


The breakout board will then plug directly into a breadboard to make a prototype as shown below. The external device can then plug into the connector.


Individual Breakout boards are available with Ethernet, USB, CAN, PS/2, RS-232, microSD, audio, Smart Card, SIM, and VGA connectors. In some cases, the connector will need to be purchased separately and soldered to the board. The .1" breakaway header pin strips will typically need to be purchased separately.

magjack magjack USB USBA CAN PS2 RCA RJ11 RS232 RS232 SD audio Smart SIM IDC VGA uVGAII pb

They are available from a variety of vendors such as ,, and In addition to direct sales, Sparkfun and Pololu also have a large number of distributors worldwide.

ConnectorSparkfunSKPangCool ComponentsPololuOtherComment
AudioXX XPC stereo jack for speakers or microphone
Coin Cell BatteryX24.5mm Battery holder - Vbat for RTC
Battery holder 6V 4AAXclosed case & switch with leads - Vin for mbed standlone
DB9XX Xconnector pins only
DB15X Xconnector pins only
DB25X Xconnector pins only
Dual row PCBX
EthernetXXXCaution: They look the same, but different companies use different pinouts on Magjacks
Flex CableX X1mm 16, 24 and 30 pin
Header PinsXXXXXNeeded for many of the breakout boards
No solder header pinsX
PS/2XXconnector pins only
RCA JackXXconnector pins only
Ribbon Cable IDEX10, 14, 20, 34, and 40 pin
Right Angle Header PinsXXWorks for R/C servo cables plugged into a breadboard or Phidgets analog sensor cables
RJ11Xconnector pins only
RS232XXXXAll have level conversion & DB9 - Pololu has handshake lines, but no LEDs
DB9 Null ModemXOften needed for above along with a M/M gender changer
Smart CardX
USB AXXUsed to connect external USB Flash drives
USB micro BX
USB mini BX
VGA connectorX XDB15 with digital out pins and RGB resistors only, no VGA controller
VGA controllerXXPicasso VGA controller with DB15 - Serial interface see Cookbook uVGAII
X-long Header PinsXXGreat for R/C servo cables plugged into a breadboard or Phidgets analog sensor cables
PushbuttonX XXX X XSPST plugs directly into breadboard - single or eight see Pushbuttons

All wikipages