„MSP430 MCU” változatai közötti eltérés
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A lap 2017. december 13., 22:03-kori változata
MSP430 MCU family from TI
Load capacitance !!!
For example, the LaunchPad uses 12pF capacitors to load the crystal we just installed, yet many crystals require 22pF.
Edit: This statement is actually incorrect. Another big thank you goes out to Jens-Michael for pointing it out to me. Thanks for reading! "12pF is the typical load for most crystals I've ever seen. But due to the electric connection, a 12pF load means [there will be 2] 24pF capacitance on each of the crystals sides. Reason is that (seen from the crystal), the two capacitors are in series to each other and parallel to the crystal. […] Subtract the ~2pF pin capacitance of the MSPs pins and you get [two separate] 22pF [for] external capacitors, resulting in 12pF load. The XCAP settings already include pin capacitance and the /2 factor."