Attached schematic for the e-Paper driver HAT.
The meaning of the yellow marked part is not clear to me.
Does this mean I can replace 105 (1 μF) with 4.7 μF and use either as available?
Attached schematic for the e-Paper driver HAT.
The meaning of the yellow marked part is not clear to me.
Does this mean I can replace 105 (1 μF) with 4.7 μF and use either as available?
Does this mean I can replace 105 (1 μF) with 4.7 μF and use either as available?
In this specific case yes, though this isn't a standard marking as others have mentioned. It seems to be an artifact of the history of these documents, as I found out. It is NOT a "caps-in-parallel" mark, as JRE's answer suggests.
I've actually been working on miniaturizing this very board recently. Waveshare's documentation is rather confusing, so to figure out what I needed, I consulted:
Comparing those, I found that Waveshare has recently bumped up the size of the caps to 4.7µF, but have historically been smaller at 1µF. I'm unimpressed with their document skills.
Here is a snippet of the relevant part of the table that I extracted from these resources when I was trying to decipher this myself, showing marked values and voltage rating:
name | eink v3 | eink v2 | newer hat | older hat | Adafruit | CrystalFontz | CF-rating |
---|---|---|---|---|---|---|---|
VSH | 4.7/25 | 105/50 | 105/50 | 105/50 | 1u/25 | 1u/25 | 10V~17V |
PreVGH | 4.7/25 | 105/50 | 105/50 | 105/50 | 1u/25 | 1u/50 | ~22V |
VSL | 4.7/25 | 105/50 | 105/50 | 105/50 | 1u/25 | 1u/25 | -17V~ -10V |
PreVGL | 4.7/25 | 105/50 | 105/50 | 105/50 | 1u/25 | 1u/50 | ~ -20V |
As you can see, it looks like the newest hat is a mix of eink v3 and the "newer hat" version.
As for me, I ended up using 105/50 (1.0µF 50V rating) as that fit the rest of the project (and I had on hand) and it is working fine for me today.
What does a capacitor marked "105 | 47 μF" mean?
"105 | 47 μF" - a 47 μF electrolytic capacitor with a maximum operating temperature of 105° C.
"105 / 50 V" - a 1 μF 50 V ceramic capacitor.