At page 13 I see completely different characteristic. It is for X7R but till now I was sure that for X5R it is like the same (in contrast to Y5V). If X5R characteristic would be different than for X7R then they would not include it in X5R capacitor datasheet.
But I have never measured it myself.
About 2/3rds of the way down you’ll see the DC bias characteristics. I wish the capacitance dropped off by only a little but this isn’t the case with ceramic caps.
muRata has a site you can find by searching for simsurfing that is a great way to find parts. There is a link for it in the murata link below.
I am surprised. You should look around between other capacitors to get more opinion.
You should not assume that datasheet certainly has no bugs. I have few times written to some IC manufacturers with the effect of next datasheet revision released.
But there at first there is an (not specific) example of how it looks like and then there are some specific characteristics and there I see -10% capacitance change.as a function of voltage and next -10% when temperature is 100° C.
My assumption always was that % capacitance change depends not on the voltage applied to capacitor but on voltage field strength in dielectric (dielectric (to set its constans) don’t knows what is the voltage at whole element but only how strong is the field here).
So your charts would provide more information if at X axis there were no voltage but voltage as a % of nominal voltage. The smaller capacitors has smaller voltages so capacitance drops much faster as a function of voltage at capacitor - I’m not surprised with it.
Assuming that X5R 0603 is 6V capacitor (chart ends at 6V) and lover X5R 1206 is 25V capacitor it looks that 0603 chart normalized to 25V will even drop to the right of 1206 chart. The 1210 charts can be for 50V or 100V capacitors so if normalized they will drop down.
Even so I am surprised. I supposed max of 20% at nominal voltage. It looks that charts I have seen (X scale to 50V) were made for probably 100V capacitors and I assumed that capacitor nominal voltage equals the right end of chart so 50V.
The capacitance change with bias voltage is a physical property of the ceramic. The ceramic has no knowledge of “capacitance” but only “sees” the field strength.
Field strength does not only increase with physical smaller size of a capacitor, but also with increased capacitance in the same package size, and this final piece of the puzzle made me realize why this graph looks so bad. Squeezing a 4.7uF ceramic capacitor into a 0603 package is sheer madness. For a more regular 100nF capacitor the graphs would look much flatter.
