What is it?

This is a project board for use with an ATtiny84 or 841. In addition to the chip itself, it provides pads for a bypass capacitor (1206), ISP header, SOT-223 regulator, and caps on the power supply (1206 or 1210), and a barrel jack. The rest of the board is dedicated to prototyping area, providing pads for an SOIC-16 or TSSOP-16 IC (or 2 SOIC-8's), a PLCC-6 (5050 LED) or SOT-23-6, and up to 6 SOT-23 mosfets in 2 banks with shared source (pads for 1206 resistor between gate and source on bottom of board) as well as area for through-hole parts.

Back in stock unexpectedly I just discovered a pile of 11 untouched panels boards sitting at the back of a bin!

Also available is a through-hole friendly version, for those who prefer to use through-hole parts when possible. This version takes an ATTiny84 (or 44/24) in the through-hole (DIP-14) package. Additionally, the regulator can be either a 1117-series or 7805 in TO-220 package (instead of SOT-223), and the caps on the regulator are also through-hole, not SMD. Pads for four SOT-23 MOSFETs are provided (instead of six) to make room for the larger area needed for the regulator and capacitors. All other features are the same.

Also available for the tiny85

Why did you make it?

I have always found solderless breadboard to be the most effective tool for prototyping and one-off projects - however, they all suffered from two problems. First, most of the best parts now are in surface mount packages, difficult to use with through-hole proto-board. By effectively putting SMD breakout boards onto the project board, these parts can be used as easily as through-hole parts. Secondly, the quality of the available protoboard was just plain lousy. These boards are manufactured to the standards of real PCBs, with copper on both sides and plated through holes.

So what could I do with this?

Using and RGB LED in the 5050/SOT-23-6 area is an obvious option - but by no means the most exciting. There are a great many very useful parts available in SOT-23-6, particularly in terms of power management. Cap-switch voltage doublers, regulators, and buck/boost drivers are all common and cheap in SOT-23. Driving some high power LEDs? Include the buck or boost converter to power them on board!

ATTiny84 Arduino Pin Mapping

Note that two pin mappings are supported by various cores. My core, available from https://github.com/SpenceKonde/ATTinyCore/ allows you to select the desired pinmapping from a submenu.