Brian, Both you and Vasi might have right. What I'm trying to say is there is a time when the lack of trust in own possibilities and acknowledges make the use of solderless prototyping necessary and a time when a project can be done without any initial prototyping tests and works from the first hardware revision and some firmware iterations. Prototyping might be necessary only for analog stuff, but never for digital stuff where things are clear if the originator of design understood what he is doing before starting the job (and not after he already did it). Use this board with pleasure, it looks Vasi has done great progress in understanding how to design a PCB. BTW, Vasi take off D1 diode which is not necessary(I've told about this several times on various topics). You can understand whyonly if *understand* the Millman's and superposition theorem. Else you'll put that diode in all your projects till retirement. Both theorems are here:
http://www.allaboutcircuits.com/vol_1/chpt_10/7.html http://en.wikipedia.org/wiki/Millman's_theorem Vasile On Sat, Oct 30, 2010 at 10:14 AM, B.Edmonson <[email protected]> wrote: > Vasile, I can understand your concerns about using breadboards, but I > think you missed the "big picture". The board is, as Vasi put it, > "for rapid prototyping". I don't think it is intended to be used in a > final product where such concerns would be an issue. Its much much > more time consuming/expensive to prototype a pcb only to find later > that you need to make a change. With a breadboard it's normally just > a matter of swapping a couple jumpers around. I think the board is a > pretty good idea. > > -Brian E. > > On Oct 30, 10:17 am, vasile surducan <[email protected]> wrote: > > It looks good (haven't patience to look closer). However why did you mix > > through hole with smd? (except the connectors, use only smd onboard) The > > lenght can be reduced with at least 10-15mm if miniaturization is your > need. > > All vias are below the microcontroller, some people does not recommend > such > > tehnique, however I see no problem only if this board is factory > > manufactured. Maybe the board has a good purpose, which I can't see it > > because I have never used solderless breadboards and have no intention to > > use from now. > > > > Using a breadboard: > > - is not safe, has poor contacts, a lot of signal interferences, the > final > > stuff breadboarded can work different than the prototype (if the > breadboard > > user will manufacture a prototype after playing with wires) and that is > a > > good way of wasting time understanding if the bug is a software or a > > hardware one > > - the user is missing the key of playing hardware: learning soldering > > tehniques, learning PCB design techniques, understanding the bitter > relation > > between the initial ideea and the final product > > > > Vasile > > > > On Sat, Oct 30, 2010 at 6:17 AM, vasi vasi <[email protected]> wrote: > > > Hi guys, > > > > > I want to present you the smallest member of Jaluino, Jaluino CELL as > > > it was named by Sebastien. Look at it as a prototype and a proposal. > > > The board is designed to be used on a breadboard and for rapid > > > prototyping. > > > > > This version use the USB bootloader of Albert and use the red LED as > > > boot mode indicator. Right now the red LED is connected at RA4 pin but > > > I'm open to suggestions. Unfortunately, the space is very small and I > > > was forced to remove the jumper which allowed disconnection of the > > > LED. You can do that removing the limiting resistor (but is nice to > > > have a boot mode indicator). Also not all components fits on the top. > > > One diode and three resistors (all smd) are soldered on the bottom. > > > The green LED is for power indicator and the blue jumper is for power > > > select (USB or external). The external power must be 5V regulated. > > > Why no regulator on board? To be able to address any project, > > > with any consumption requirements. > > > > > The board don't have an ICSP connector (no more space) but having > > > external pins, the microcontroller can be easily programmed if you > > > insert the board on a breadboard (without the fear of bending pins). > > > > > Well, the initial version was a lot bigger but Sebastien suggested that > > > if can be of maximum 5cm long it can benefit from the cheapest > > > Seeedstudio service and I considered it a good advice.. > > > > > I hope that this board will be useful for someone. > > > > > -- > > > Vasi > > > > > -- > > > You received this message because you are subscribed to the Google > Groups > > > "jallib" group. > > > To post to this group, send email to [email protected]. > > > To unsubscribe from this group, send email to > > > [email protected]<jallib%[email protected]> > <jallib%[email protected]<jallib%[email protected]> > > > > > . > > > For more options, visit this group at > > >http://groups.google.com/group/jallib?hl=en. > > -- > You received this message because you are subscribed to the Google Groups > "jallib" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]<jallib%[email protected]> > . > For more options, visit this group at > http://groups.google.com/group/jallib?hl=en. > > -- You received this message because you are subscribed to the Google Groups "jallib" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/jallib?hl=en.
