Introduction: ATtiny Dev Board / Tinyduino
This is an ATtiny Dev Board. Designed for the ATtiny line of microcontollers from atmel. Its made to be small, simple to build and easy to use.
This board has following features:
- Female headers for easy prototyping
- Build-in 1A 5V voltage regulator
- 8-Pin socket to change out microcontrollers
- ISP-Header for programming
- Power selcet switch, using voltage regulator or the USB power of the programmer
- Reset button
- Power on LED
Step 1: Required Parts / Tools
1x Perforated PCB
2x 1x4 Female headers
2x 1x3 Male pin
2x 100nF Ceramic capacitor
1x Resistor 10k ohm
1x Resistor 220 ohm
1x Slide Switch (SPDT)
1x Momentary push button
1x LED 3 or 5mm any color you like
1x 8 Pin DIP socket
1x 7805 Voltage regulator
1x Terminal block
1x Some wire
- Soldering iron
- Helping Hands
- Box cutter
- Wire stripper
- Wire cutter
Step 2: Score and Snap Your PCB
My PCB was alrady 18 pads wide so i only need to shorten the PCB to 11 pads long, i did this by counting down the 11 rows and started to score the 12 row with a boxcutter (BE CAREFUL). After 5 to 10 passes i snaped the board in half. If your board is wider as mine you need to do the same for the other side too but this time 18 pads instead of 11. If done corrctly the borad shoud look like the board in Step 1
Step 3: Bend and Solder Resistors
The 10k ohm resistor is bend so that it spans 4 holes. And the 220 ohm resistor is bend to span 5 holes. Solder them in as seen in the picture. And use the PCB layout as reference. Its helpful to own Helping hands so its easier to solder, it's best to solder one leg first then applying pressure to the part and reheat the joint so that the part aligns with the PCB. Now you can solder the second leg. You maybe want to use some kind of tool to apply pressure since the part could get hot quite quickly.
Step 4: Cut and Bend Jumper Wires
Take some wire which fits through the holes of the PCB and cut to sections of 2 cm (0,8 inch) in lenght. Bend them so they span 4 holes. Use pliers for best results.
Step 5: Solder Jumpers
Solder the jumpers as seen on the picture and described on the PCB reference. Use the same method as described in Step 3, to get the jumpers straight.
Step 6: Solder 8-Pin Socket
Solder the socket as seen on the picture and described on the PCB reference. The notch in the socket needs to face towards the 10k ohm resistor. Again follow Step 3 to get the socket straight.
Step 7: Solder the Button
Solder the button as seen on the picture and described on the PCB reference. My button had only 2 legs but 4 legs work as well, watch out for orientation the poles are left and right. By now you know the drill, solder one leg, align, solder the rest.
Step 8: Solder the Capacitors
Solder the capacitors as seen on the picture and described on the PCB reference. These are non polarised capacitors so you don't need to worry about orientation. Get em straight.
Step 9: Bend and Solder LED
Bend the LED leads so they span 4 holes. Solder the LED as seen on the picture and described on the PCB reference. Watch out LED's are polarised meaning they have a positive and a negative leg, the positive leg is the longer one and should face the 220 ohm resistor. If you don't get the LED right it won't light. But don't worry though, nothing will blow up, simply desolder the LED and turn it around and solder it in again.
Step 10: Solder the Switch
Solder the switch as seen on the picture and described on the PCB reference.
Step 11: Solder the Voltage Regulator
Solder the regulator as seen on the picture and described on the PCB reference. The regulator has three pins, seen from the front left to right:
Pin one: Vin
Pin two: GND
Pin three: Vout
Get this right or the circuit won't work. I bend mine down so it has a lower profile, i recommend to do the same.
Step 12: Solder Male and Female Headers
Solder the headers as seen on the picture and described on the PCB reference. Try to get them nice and straight. They are the most difficult to solder part, use helping hands if possible.
Step 13: Solder Screw Terminal Block
Solder the screw terminal block as seen on the picture and described on the PCB reference. Soldering may take a while since the screw terminal block contains a lot of metal which draws heat from your iron, avoid touching the block, it could be very hot.
Step 14: Solder It Together
Solder it all together, this is the most difficult and time consuming step. Use the PCB reference, go slow and carfully, you don't want to do a mistake here. Maybe print the reference out to help you soldering.
Step 15: Testing
Test your circuit. Plug an ATtiny in the socket, write some code and upload it using an ISP-programmer. I am using the USBTinyISP, TSJWang did a great tutorial how to build one on your own.
If everything works, congratulations your are done and now a proud owner of your own DIY ATtiny Dev board. :D
If nothing works, it's time to troubleshoot. Check your wireing, are your solder joins good, is everything plugged in correctly. I hope you can solve your problem quickly. Good luck.
Step 16: Finsh
Now that you are done building this board, get prototyping. Or expand and redesign my board. Tell me if you build one, and how it went, what did you do differently. I hope all goes well. Also feel free to ask questions, i try to help were i can.