Can the IN5817 Schottky Diode be used in place of a B5819W-TP Diode on a Max7219 7-segment display board? The main diff seems to be the 20v vs the 40v. Does that affect the display circuit?
I need the through hole type.
If you need through hole, that other part might be suitable enough. The DC reverse voltage is a maximum rating. Technically, it would fail at a lower voltage compared to B5819W-TPMSCT-ND. This can be a gray area because I don’t know what the diode is being used for in the circuit, but the board voltage is 5V. So technically speaking, the 40V choice is already overkill. Keep in mind that this through hole variant has a lower forward voltage drop. This is more concerning as I don’t know to what degree the output voltage needs to be tuned to. Again, it kind of depends on what the diode is used for. I would actually recommend 1N5819-TPCT-ND as it is closer in forward voltage.
I’m curious as to why you are considering a through hole part instead of a surface mount part. The board would have a surface mount layout. It’s not that you cannot do this, but it is going to be harder to solder.
I am very new to creating PCBs with capacitors and diodes. I have not done any surface mount soldering in the 4 years I have been working on my flight sim components using Arduinos. This project I am undertaking is an effort to branch out into electronics a bit more and to create a flight sim NAV/COM radio with two 5 digit 7-segment displays. So I am stumbling my way through this exercise.
The schematic I am considering emulating I downloaded from the Mobiflight github repository and it shows a 1N5819 diode in the schematic but pads in the PCB. So I am a little confused.
When I search for that particular diode in DigiKey search bar, I get a page of only through hole components. So I think, good I am not experienced at SMD soldering so that could work if I revise the schematic and especially the PCB to have holes instead of pads.
But a 1206 sized SMD I think I could solder by hand if need be.
I guess I don’t really care whether it’s SMD or THT but I am confused at which one I should purchase for on this project..
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Follow-up. I am looking at two different schematics, The B5819W is being used on a different board than the one I mentioned above. It is most definitely an SMD component on the completed board based on this schematic.
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Again, I am still slogging through getting the education I need to create this radio.
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Oh, I see the issue. So this happens a lot for many types of designs. 1N5819 is only a partial part number in the schematic. Many board designers leave off characters for whatever reason. When you search for this only, you’re going to get mixed results (both surface mount and through hole, this time a majority are through hole). If the pads do match the design for the SOD-123, then I’d go for any of these in that case. It’s possible the designer of the board originally used an alternate if the surface mount version of 1N5819 wasn’t available at that time. If you want to confirm dimensions, you can just measure the pad spacing (length and width) and confirm by comparing to an online reference for the SOD-123. Surface mount parts like these can be hand soldered, usually with a pointed, thin tip.
I think I have enough soldering experience now to be able to hand solder that. Its a little larger than a 1206 size so shouldn’t be a problem. Its very close to the pads designed on the PCB.
Thank you.