Hi Circuiters
I recently discovered the strong applied-voltage dependence of a SMD multilayer ceramic cap's capacitance; up to ~-80% of the nominal capacitance when biased at 50V. This explains why my decoupling with 1uF 0805's wasn't as effective as I expected, since I was introducing only 200nF when de-rated. However the manufacturers don't seem to acknowledge this behaviour in the headline figures. Does anyone know of a way to search out caps that maintain most of their capacitance at 50V?
eg. RS-online have 76 products matching: Surface mount, 50V, 1uF. I don't want to read 76 datasheets but there's no high-level filter to discriminate on dC/dV. The link below is interesting but the conclusion is that generally the bigger the case, the fewer compromises have been made and so dC/dV is probably lower. Is this really the best I can do?
https://www.maximintegrated.com/en/app-notes/index.mvp/id/5527
I recently discovered the strong applied-voltage dependence of a SMD multilayer ceramic cap's capacitance; up to ~-80% of the nominal capacitance when biased at 50V. This explains why my decoupling with 1uF 0805's wasn't as effective as I expected, since I was introducing only 200nF when de-rated. However the manufacturers don't seem to acknowledge this behaviour in the headline figures. Does anyone know of a way to search out caps that maintain most of their capacitance at 50V?
eg. RS-online have 76 products matching: Surface mount, 50V, 1uF. I don't want to read 76 datasheets but there's no high-level filter to discriminate on dC/dV. The link below is interesting but the conclusion is that generally the bigger the case, the fewer compromises have been made and so dC/dV is probably lower. Is this really the best I can do?
https://www.maximintegrated.com/en/app-notes/index.mvp/id/5527