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Power supply. Design in PCB

We are going to design and to construct an adjustable power supply using the components that we have seen in the subject of appeased Electronics.

In the image of the left we have an example of objective of the practice.

The process that was place years old back, was the use of virgin plates (a complete copper face), where we labeled the tracks with a special labeller, and soon we passed it to a dissolution that attacked copper. Spent some minutes, it is washed and the red of the labeller with alcohol takes off. The last step is to drill the plate.

Nowadays, thanks to Internet, we have the possibility of designing our prototype (For example with Proteus), of creating the file of the plate and soon to send it so that they make it.

The price does not arrive at the 2 €, and as all we understand, by that price it is not worth the trouble to resort to the traditional method.

Companies as JLCPCB, offer this service, but they demand a series of requirements that we must fulfill so that the management and the manufacture of the plate are possible, among them, to create our file of the type Gerber

To create a plate PCB step by step

1

We begin with an Integrated circuit of family 78XX and 79XX.  As we saw in the section of power supplies, electronic encapsulations are component where in his interior it has of a series connected semiconductors of such form that regulate and stabilize an exit tension. They are called of family 78XX because according to he is the XX, we will have a tension stabilized to a fixed tension. For example, if he is 7805, the exit tension will be 5 volts. The simple circuit but for this regulator is in the following image that we are going to mount with proteus.

It is necessary to consider that we must leave a space sufficient to put a radiator (heat dissipator). That dissipator is screwed to the metallic plate of the regulator, adding previously grazes thermal

As we can see in the image, it has three legs, that correspond to the entrance, the exit and to the reference tension. These circuits are present to a large extent of the power supplies, due to their characteristics as far as stability, protection, simplicity and economy.

The family

The range of tension and currents that they provide is fixed and, since we have commented before, we must both look at last number to see the tension of exit (it goes from 3.3v to 24v) with a current of 0.1A 3A.

We design our power supply and we passed it to proteus. Important We must add to our name in the plate or the name of the equipment

   To create our file PCB. For it we will see the following video.

Previous the tutorial video makes reference to an integrated circuit very used, and therefore, with great productions that a very low price of production has made possible.  This circuit we are going it to mount as second practice

Once we have created the Gerber file, we go to the JLCPCB webpage. This company offers very economic prices but with somewhat expensive shipments. The options of manufacture of the plate are varied and the good finished ones. It is possible to emphasize that it can make plates multilayers. These plates us more connections in the same space (if the components fit, clearly). In the following image, we can observe as the drill makes contact with one of the layers. In the plate with double it castrates, communicates a track superior with the track of the other house. In the one of 4 layers, the superior makes contact with the third layer….

5º Pasamos all the data to calculate what costs to us to make our plate. The result we see it in the following image

Other options that are indicated in the sign?

Is the total price something smaller to 12 € with bearings, which causes that each plate costs 1.2 € (is worth the trouble to walk with acids to do it we? )

5º Llegamos at the point to make a decision in class. The class can choose by one of these two options

a) Decide all to us by a single project, in which case, each group we must make the complete practice and Only one will be sent to the manufacture. The rest we received the plate and we mounted it according to the chosen design

b) It is decided on two different works, in which case, one becomes just like in the section to, only that we must send two Gerber archives and the price get dearer

5º Once the plate arrives, we mounted in class and we verified the operation

6º Another alternative to create the file, is to use pcb wizard, whose tutorial we have it in the following connection. It is necessary to consider that, although is a very popular program, are not generated the archives well to gerber, although is solutions in Internet that correct this error. We are the tutorial in the following connection

To show/To hide PCB with Wizard

PCB Wizard

Another program that we can use is pcb wizard, that has the advantage to execute itself without installation. When using this program, we have a folder with examples, between which we have the 555.

  1. The steps to create compressed the Gerber file are the following
  2. We lower the program from DRIVE
  3. We execute the program and we opened the file of the 555 that we have in the Example folder. Astable.pcb is called 555 555 pcb wizard
  4. When opening it, we have an image as one is next.
  5. It appears a vertical menu of eyelashes in the left part. To select Artwork
  6. If the file is protected, we must select Cases out - > Unprotect Document
  7. We select to the plate and right button soon. click in Exposes to eliminate outer surroundings, so that we have left only the plate without external line
  8. Double click in the text to change the name of the plate export to gerber
  9. To go to Tools - > CAD/CAM - > Export Gerber. First it is to select to the folder destiny in Knows ace. Soon to select as it is indicated in the following image
  10. Once finished, we beat in Ok and 4 archives are generated. It is necessary to compress them in zip for the shipment to the factory.

 

But info in web-> http://oldwebsite.denford.ltd.uk/support/89-tutorials/104-pcb-routing

Final work

To carry out a complete work indicating each one of the steps that there are to give to realise a plate PCB (bistable Source or), so that it is enclosed in each section, a help image.  Once finished, to create a folder that is called PCB, where a pdf with the tutorial and the Gerber archives is included that there are to send)

Design PCB