ATtiny26 development board

REVISED.

Development boards save time otherwise spent wiring up AVRs on breadboards and then pulling them up to make space and then re-wiring them up again later on. This board already has best practice support components around the AVR such as the noise and static protection on RESET and the bypass capacitor for the AVR power supply, which greatly improves the accuracy of the ADC.

This board also supports ATtiny261, ATtiny461 and ATtiny861. The top silk has been put on with the toner-transfer technique.

features

• a standard 10-pin AVR ISP socket
• typical RESET protection circuitry
• a decoupling capacitor for the AVR supply
• GPIO pins connected to a hookup-wire-friendly socket
• separate tie points for PB4 and PB5 to keep the traces short around the crystal
• connectors for TTL-level RS232 in both the default and alternate✝ positions for use with the RS232 to TTL adapter
• a selector to choose the power source from either 1) the ISP connector, or 2) the DC power jack
• a socket for a crystal along with the support capacitors
• a “power OK” indicator
• external best-practice circuitry for the ADC

✝ for ATtiny?61 parts only

changes

Revision 2 is laid out for a 20-pin ZIF socket, is easier to fabricate with fewer 0Ω links and has two TTL-level RS232 connectors. The clearances of all pins and vias have been set to 3500 mils and the drill holes set to 1500 mils regardless of the actual diamater of the pins. This helps to aim the drill bit for construction at home.

download

The archive contains a gschem schematic and a single-sided pcb layout.

• t26-dev-board_2010-01-23.tar.gz - revision 2
• t26-dev-board_2009-06-20.tar.gz - revision 1