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Atmega328 - Newbie design

anishkgt

Hi All,

 

A little new to the Eagle PCB, so please bear with my silly questions. I had designed a single sided board and all ready for etching. Printed the circuit on paper, only to find out that ATmega328 does not fit in the printout. Download all available libraries of eagle and non seem to be working.

 

 

Any help would be appreciated.

  • 0 in reply to jc2048

    wow that was a mouth full image. So to understand. I need to separate the mains AC from the dc side. GOT IT ! image About the resistors, which one ? the AC mains is 240v with a 5amp fuse in it. The PCB transformer is rated at 9v 1.5VA. This is the below circuit.

    image

  • 0 in reply to anishkgt

    I thought the devices down the board were selection links. They're LEDs, so of course you need the resistors.

     

    To carry 5 amps, at 25C, on a board with 1oz copper, with no more than a 10C temperature rise you need a track width of something like 2.8mm (that applies whatever the voltage). However a fuse doesn't blow at the rated current (at least not quickly - look in a datasheet which will have a graph of time-to-blow against current), so you would do well to increase that to cover more than 5A. If you want to see how current varies with track width there are plenty of track width calculators online.

     

    I can't go any further than this with the mains side. It's not something that I normally do and I'm not qualified to hand out advice as to how it should be done (I know what you shouldn't do, but I'm less clear on what you should do). In particular, I can't advise you on the clearances you need. I know it gets complicated, because it includes making judgements about factors like the environment the board will be in, and being careful to distinguish clearance (the distance through the air between two conductors) and creepage (the distance along a surface between two conductors) which may have different ratings.

     

    Are you sure you really need to be doing the mains layout? Can you not do what you want to do with a PSU and a solid state relay?

  • 0 in reply to anishkgt

    First off, uncheck the scale to fit box as shown below to get a true 1:1 printout.

     

    image

  • 0 in reply to sparky2k7

    nope it was not. It was the driver of the printer that had the generic rather the manufaturers recommended driver. installed the driver and all worked well.