Atmel ATTINY26 Prototyping PCB (Bare Board)

This printed circuit board is perfect for quickly getting your next Atmel ATtiny26 microcontroller project going. The circuit board includes all connections and footprints for an LP2950 voltage regulator, resonator or crystal, reset circuit, power jack and switch, RS-232 level converter with DB9 connector, and 10-pin in-circuit programming header. All of the power and I/O lines are brought out to the edge of the prototyping area for easy access. The picture to the right shows a board with all optional components populated.

To save space, the PCB is designed to have the main microcontroller and supporting circuitry populated with surface-mount packages. The microcontroller must be in an SOIC package, and the voltage regulator footprint is for a DPAK package. The remaining resistors and capacitors are in 0603 packages. The RS-232 circuitry, reset pushbutton switch, resonator or crystal, power jack and switch, and in-circuit programming header use through-hole components. This prototyping board is also available with the surface-mount components already assembled.

The prototyping grid has pads connected in pairs and triplets for easy circuit building in configurations similar to those you would use on a solderless breadboard. Five longer bus lines simplify distribution of nets with many connections, such as power and ground lines. All of the prototyping grid connections are routed on the bottom layer of the board so that they can easily be cut if necessary, and all of the connections are clearly indicated on the white silkscreen on the top side. The grid can hold up to two 40-pin DIP packages and two 20-pin DIP packages or up to eight 20-pin DIP packages.

Feature summary

• 3" x 4" board
• High-quality, double-sided PCB with soldermask on both sides
• Footprints for SOIC-package ATTINY26 microcontroller and DPAK-package voltage regulator
• Holds crystal and two capacitors or 3-pin ceramic resonator with built-in capacitors
• DB9 connector pins brought out so that it can be used for non-RS-232 purposes
• Prototyping area
  • 29 × 25-hole grid with standard 0.1" spacing (16 holes missing in bottom corners for mounting holes)
  • 0.042" -diameter plated-through holes
  • Five bus strips
  • Pads connected in groups of two or three
  • Silkscreen clearly indicated connections
  • Solder mask on both sides
  • Four 1/8" mounting holes