Tried my hand at designing my first custom PCB for a servo driver, but as it turned out, I had the pins for the voltage regulator the wrong way around.
Also, for some reason the set of SMD resistors I bought a long time ago only had series of 1, 3.3, 5.1, 7.5 and 9.1 ohms, so I had to stack a 5.1k and two 33k to get the desired 3.6 ohms. (Ignore the 36k silkscreen, I found out during later breadboarding that 36k was way too high and caused the LM350’s sense current to add significant error.)
I’ve been designing/building electronics for a long while now and I have found that the three-legged devices, especially transistors, are the worst for showing up with the wrong pinouts. Voltage regulators are pretty safe now since all the manufacturers use the same pinout for each type. The greatest source of confusion come from schematic libraries that do not match layout libraries. I used OrCad for a lot of years and have well-learned the habit of checking any order from a supplier with the datasheet from the ACTUAL manufacturer that is being ordered against the layout library footprint AND the schematic symbol all for consistency.
Believe me, patching 16 transistor footprints on each of 10 protos is not fun.
Haha, I know when that happens. Although it was a “line” PCB, don’t know how to call them properly… All soldered togehter, just to find my LM358 getting extremely hot ^^
I just didn’t think about pinout that time, no idea why, I just assumed input ist left, output middle and control at the right…
Heh, did you get your component library from ultralibrarian? Seems like a significant number of theirs are a project-breaking disaster, and most of the rest are abhorrent in non project-breaking ways.
It’s literally faster and easier for me to create my own library from scratch than find, download, verify, and fix libraries from the internet.
Where’d you get your boards made?
Tried my hand at designing my first custom PCB for a servo driver, but as it turned out, I had the pins for the voltage regulator the wrong way around.
Also, for some reason the set of SMD resistors I bought a long time ago only had series of 1, 3.3, 5.1, 7.5 and 9.1 ohms, so I had to stack a 5.1k and two 33k to get the desired 3.6 ohms. (Ignore the 36k silkscreen, I found out during later breadboarding that 36k was way too high and caused the LM350’s sense current to add significant error.)
I’ve been designing/building electronics for a long while now and I have found that the three-legged devices, especially transistors, are the worst for showing up with the wrong pinouts. Voltage regulators are pretty safe now since all the manufacturers use the same pinout for each type. The greatest source of confusion come from schematic libraries that do not match layout libraries. I used OrCad for a lot of years and have well-learned the habit of checking any order from a supplier with the datasheet from the ACTUAL manufacturer that is being ordered against the layout library footprint AND the schematic symbol all for consistency.
Believe me, patching 16 transistor footprints on each of 10 protos is not fun.
Haha, I know when that happens. Although it was a “line” PCB, don’t know how to call them properly… All soldered togehter, just to find my LM358 getting extremely hot ^^
I just didn’t think about pinout that time, no idea why, I just assumed input ist left, output middle and control at the right…
Heh, did you get your component library from ultralibrarian? Seems like a significant number of theirs are a project-breaking disaster, and most of the rest are abhorrent in non project-breaking ways.
It’s literally faster and easier for me to create my own library from scratch than find, download, verify, and fix libraries from the internet.