68kMLA Classic Interface

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Capacitors are *not* simple...
Posted by: Melkhior on 2024-02-05 05:38:16
Given the many discussions on capacitors replacement & the whole polymer vs. tantalum vs. ceramic, here's an interesting video I just discovered on the subject:

James Lewis - They're JUST Capacitors

Voltage impact on ceramic capacitance is also discussed in this article:

Temperature and Voltage Variation of Ceramic Capacitors, or Why Your 4.7µF Capacitor Becomes a 0.33µF Capacitor

And as the link is not obvious to find, for the Samsung stuff that JLCPCB offer as "basic" parts (they are not the worst, I just have a lot of them in my design so they are of interest):

Graphs for that nice 10uF 25V 0805 CL21A106KAYNNN at $0.0104 qty 1

Turns out it's about 5uF at 5V and 7uF at 3.3V... but you can get 9uF or more at 1.8V or less! Time to revisit some part numbers and packages, I guess.

And from the video, the tantalums doing bulk for the MC68882 on my homemade IIsi PDS adapter will *not* blow up, they are polymer, not MnO2!
Posted by: cheesestraws on 2024-02-05 05:58:07
For falling down this rabbit hole, I've always found http://iequalscdvdt.com/ a really interesting site.
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