Concept to final product

Hi All,

I have worked on this small project auto control of a LT panel using arduino w relay. I am happy with everything the way it works/code etc. I have bootloaded a standlaone atmega8pu chip and have also put my code in it.
The problem - how to create first sample circuit and see how it performs, before spending money on a printed PCB. I have some prototype boards which I could use , but the soldering is often messy in that one and if one component is faulty , replacing it is pain. How do you guys do it ?

  1. Could you post your self soldered sample circuits.
  2. Self created PCB, I know there are several ways out there to use UV copper plate, etching it using Toner method etc, but which one is best and consistent to use?
  3. How do you go from concept to a final usable product. Do you still use Atmega or you switch to another microcontroller.

Thanks in advance.

and if one component is faulty , replacing it is pain. How do you guys do it?

Solder sucker and/or solder wick.

Use sockets. Solder to the socket pins and stick your sensitive chips and bits in after the heat is gone.

It's amazing what you can plug in and out of sockets. A 40-pin narrow socket can take a 328P and still have 2 rows of 6 holes and pins free.

Also, hot glue can be your friend but epoxy is closer to permanent.

I generally make a stand alone arduino on boards from Adafruit.

These days there's no reason to mess about with UV resist, acid etch, drilling etc. Just get the board made at a commercial service. I use OSHPark a lot. They send you 3 copies of the board in about 2 weeks on their standard service. There are many vendors out there who will do it faster.

Then I usually end up making a few changes on the board: glue a forgotten pullup resistor across the top of some component, for example. If I want more boards, then I make that change to my PCB layout and get more made.

I find the time and effort saved by using a proper PCB instead of point-to-point wiring a perf-board makes it faster to wait for the custom PCB.