Another BPA200 post: Need some advice on finalizing design

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It looks like the antek transformer would be alright, tying red and orange to make the CT. I guess the footnote is to avoid people unbalacing the transformer by using only one secondary or playing with weird configuration with the primary.

Btw, the antek transformers might come cheaper. The 400VA is 51$, the 800VA is 84$ and the 1000VA is 100$ but you have to order from them.

As a side note, I've stopped etching my own boards. The price and quality of the cheap fab houses in China is just unbeatable, especially for small boards. The only downside is the one month wait time to get the board (even worse now with the Chinese new year).

Edit: the suggestion of using the drv134 is to get a differential signal so that you can use all inverting lm3886 and not half inverting, half non inverting. The lm3886 is slightly better in inverting config.
 
So, would you suggest using something like ExpressPCB and then ordering through them? Any other software suggestions and places to order PCBs in the US?

Also, any recommendation on the mute circuit strategy that I had mentioned earlier?

I'll check out the Antek transformers, I think they have an ebay store too.
 
So, would you suggest using something like ExpressPCB and then ordering through them? Any other software suggestions and places to order PCBs in the US?

OSH Park makes good PCBs. I hear good things about KiCAD software but have no personal experience with it. Some swear by Eagle, but last I tried to use it, the UI made me lose my mind. Maybe the company that bought it decided to make it usable. I also seem to recall some quite usable demo versions of OrCAD and Altium being offered by their respective vendors. Both OrCAD and Altium are industry standard, so if you get over the learning curve, you'll have a useful skill that could be applied in the job market should you so desire.

Also, any recommendation on the mute circuit strategy that I had mentioned earlier?

See Post #12.

I'll check out the Antek transformers, I think they have an ebay store too.

Why bother with ePay? Just go through their website. The Antek Transformers are incredibly value for the money and John usually ships them within one business day of order placement.

Tom
 
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So, would you suggest using something like ExpressPCB and then ordering through them? Any other software suggestions and places to order PCBs in the US?

Expresspcb is quite expensive and ties you to a pretty bad piece of software. They're fast and quality is ok on the other hand.

If you want an US factory, OSH park is a good compromise in between speed and cost. Quality is very good too. For small high quality boards in small quantity, it's really worth it.

If you don't mind waiting a bit longer, it's worth considering a Chinese seller, such as smart-prototyping (that's the one I'm usually using). Quality is a bit worse but that's no problem with such simple pcb.

To give you an idea, for 8 pieces of 5.5 inch square pcb (using mine as exemple), OSH Park will cost 82.5$ (for 9 pcs actually). Smart proto will make 10 pieces for less than 20$ shipped.

Software wise, I'm using Eagle myself but it's just because I started with it. I tried Kicad (much more flexible and powerful than Eagle freeware) but couldn't get used to the interface and the libraries management.
 
I took you alls suggestion. I’m designing the layout for the PCB in Kicad. Just one question when I send the files to Osh or any other pcb manufacturer, which gerber files do they expect? I’m doing bottom Cu, top Cu, top silkscreen, bottom solder mask and the drill file seems to be auto generated based on the footprints. Any other layers? And do I just zip all these and send them?
 
The beauty of OSH Park order system is that you can directly upload your kicad files and they do the gerber conversion. You can even check instantly if the conversion is correct.

For manufacturers asking gerbers, they usually specify what they want and how they want it labelled. You then zip it all and upload.
 
Here is phase one of the project. I am attaching the PCB and schematic. Please let me know if anything needs to change or looks off on the PCB. For the GND plane I have used 0.2mm clearance, I hope that is enough for OSH park. For the Bridge I am using a 4-pin connector instead because I plan to mount the bridge on the chassis connected to the heatsink. The linear regulator ICs are infact MC78Lxx and MC79xx so the footprints have been adjusted for their respective pinouts, but please let me know if I messed up somewhere. I plan to add more 0.1uf caps on the LM3886 +/-V rails.
 

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Thanks Tom, I overlooked that little detail. I will make that change and switch the LM317 and 337.

@HIPCHECK, thanks a lot I appreciate it! I'm currently sticking with through hole components. But I'll let you know if I end up needing SMDs

@Marrk The PSU datasheet is a little weirdly drawn, but basically it should use a single bridge with a CT transformer. I'm not sure if they intend for people to use those many caps per chip, I supposed it would be nice to do so .. but that would mean about $200 just in capacitors alone lol. Certainly not going to do that.
 
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