Both versions back in stock in quantity!

What is it?

This is a project board for use with an ATtiny85 (or '13, '25 or '45) . This provides an outline for the ATtiny85 in either SOIC-8 or DIP-8. Each outline has its own 1206 bypass cap. It also provides holes for an ISP header, and pads for SOT-223 regulator and associated 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 a variety of surface mount parts in addition to some traditional DIP prototyping space.

Also available for the tiny84

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.

Features

• Use either SOIC or DIP ATTiny85
• One spot for 5050 LED or SOT-23-6 package
• Two sets of pads for 2 SOT-23 MOSFET w/pads for resistor between gate and source
• One set of pads for an SOIC-16 (front) or TSSOP-16 (back)
• Multiple smaller SOIC or SSOP parts can be placed in one of the larger footprints, as shown.
• Pads to mount a barrel power jack (center positive), input capacitors
• Pads for one SOT-223 voltage regulator
• Exposed GND and Vcc traces for easy power and ground wiring.
• 11-row long traditional DIP prototyping area
• Now shipping new revision of SMT/TH version: improved power and ground routing, with more connection points to those, and better silkscreen: reset pullup resistor marked "10k", decoupling cap marked :0.1uF", ISP pins better labeled, all Vcc and most ground connection points marked, major Vcc connection points enclosed in white outline.

Through-hole version

• No outline for SOIC-8 version of the Tiny85.
• All required passives (decoupling caps, input + output caps on regulator, reset pullup) are through-hole, not SMD.
• Regulator outline is through-hole - pins line up for 7805 or 1117-series regulator in TO-220. These have different pinouts, so be sure to check the markings on the underside of the board.
• All other features identical.

Example project

In the above picture, you can see an example of what a finished project using this project board might look like. Note that this is a prototype board - the ones shipping now are as shown in the main picture.

That board is connected to a 433mhz RF receiver (just off the side of the frame), LDR light sensor and a touch switch (the three-pin connector). One of the MOSFET channels is used to drive a pair of 10v 3W LED panels off the 12V input (using that large power resistor as ballast), controlled by the touch switch - this is used for under-shelf lighting. Meanwhile, an AOZ1282 buck converter generates 4.5v to power a red power LED (rated 5W, but run well below that); when a signal indicating that I've closed the door to my room is received over RF, and the room is dark, it turns on the red light so I can see my way back to bed.

Use with ATtiny412 too!

A customer doing this on the old version tipped me off about this. He was cutting the power trace, and installing an ATtiny 412 (rotated 180 degrees so ground was the same pin as ground for t85, then connecting power accordingly. I made sure this would still work in the improved SMT-friendly design and then some: Power can be disconnected from the not-power-on-412 pin by cutting just the small trace to the right of the throughole outline, on the top. and instead of the usual decoupling cap on the top, flip it over and you can solder one between Don't install the usual decoupling capacitor. To get power to the the pin marked 0 (which is the t412's power pin, solder a wire between the exposed Vcc patch on the underside and pin0 of the TH footprint, and connect the 0.1uF decoupling cap between the Vcc on underside and the mysterious exposed Gnd patch. And right there the top, a similar Vcc pad. can be connected to t412's Vdd pin to power it.