Capacitance versus voltage for X7S caps?
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From: Joerg on 28 Mar 2010 16:45 legg wrote: > On Sat, 27 Mar 2010 08:56:48 -0700, Joerg <invalid(a)invalid.invalid> > wrote: > > >> Maybe I am doing something wrong with the search input fields. How do >> you get the capacitance versus voltage graph for the TDK capacitor with >> the part number C4532X7S2A475M ? >> > Drop the last letter or use C4532X7S2A475K > > I found this by specifying a characteristics search in multilayer > capacitors >0.1uF, then specifying tempco (x7s) and series (4532) > > If you select only a voltage range, impedance range and frequency, you > will be offered a window allowing comparison of all suitable part > numbers individually or on the same graphs, regardless of body size or > tempco or class. This is the easiest way to see X7R and X7S offerings, > side by side. > Ok thanks, now I got it. Strange that the tool doesn't recognize their own part numbers. Still, why do they stop at 50V while it is a 100V part? I really prefer the old datasheet method. Faster, and you can store it as a document for ECO release. An online tool result doesn't necessarily cut the mustard when the agency guys audit my designs. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Joerg on 28 Mar 2010 16:46 JosephKK wrote: > On Sat, 27 Mar 2010 08:56:48 -0700, Joerg <invalid(a)invalid.invalid> wrote: > >> John Devereux wrote: >>> Joerg <invalid(a)invalid.invalid> writes: >>> >>>> legg wrote: >>>>> On Fri, 26 Mar 2010 06:59:10 -0700, Joerg <invalid(a)invalid.invalid> >>>>> wrote: >>>>> >>>>>> legg wrote: >>>>>> And that's not telling anything about voltage tolerance. The temp >>>>>> curves are usually in the datasheets, voltage graphs aren't anymore >>>>>> :-) >>>>>> >>>>> The TDK graphing utility is really quite good. Perhaps you might >>>>> encourage this kind of data service by buying only those parts for >>>>> which info IS provided. >>>>> >>>>> TDK will even plot multiple selections on the same axis - just be very >>>>> general about your initial selections - voltage, body size and maybe >>>>> tempco. >>>>> >>>>> http://www.tdk.co.jp/ccv/index.asp >>>>> >>>> -> "No results were found" :-( >>>> >>>> I could try over and over again to make it spit out a capacitance over >>>> voltage graph, on the client's nickel. Or just move on to another >>>> brand ... >>> Works fine for me - quite nice, I agree it should be in the datasheet. >>> >> Maybe I am doing something wrong with the search input fields. How do >> you get the capacitance versus voltage graph for the TDK capacitor with >> the part number C4532X7S2A475M ? >> >> [...] > > Since you stated 4.7 uF @ 100 V i looked in the medium voltage list, > under 4.5mm x 3.2mm [EIA 1812] and there is at the bottom of the list. > > -60 % at 50 V. But the graph stops at 50V while it's s'posed to go to 100V ... -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Fred Bartoli on 28 Mar 2010 16:59 Joerg a �crit : > JosephKK wrote: >> On Sat, 27 Mar 2010 08:56:48 -0700, Joerg <invalid(a)invalid.invalid> >> wrote: >> >>> John Devereux wrote: >>>> Joerg <invalid(a)invalid.invalid> writes: >>>> >>>>> legg wrote: >>>>>> On Fri, 26 Mar 2010 06:59:10 -0700, Joerg <invalid(a)invalid.invalid> >>>>>> wrote: >>>>>> >>>>>>> legg wrote: >>>>>>> And that's not telling anything about voltage tolerance. The temp >>>>>>> curves are usually in the datasheets, voltage graphs aren't anymore >>>>>>> :-) >>>>>>> >>>>>> The TDK graphing utility is really quite good. Perhaps you might >>>>>> encourage this kind of data service by buying only those parts for >>>>>> which info IS provided. >>>>>> >>>>>> TDK will even plot multiple selections on the same axis - just be >>>>>> very >>>>>> general about your initial selections - voltage, body size and maybe >>>>>> tempco. >>>>>> >>>>>> http://www.tdk.co.jp/ccv/index.asp >>>>>> >>>>> -> "No results were found" :-( >>>>> >>>>> I could try over and over again to make it spit out a capacitance over >>>>> voltage graph, on the client's nickel. Or just move on to another >>>>> brand ... >>>> Works fine for me - quite nice, I agree it should be in the datasheet. >>>> >>> Maybe I am doing something wrong with the search input fields. How do >>> you get the capacitance versus voltage graph for the TDK capacitor >>> with the part number C4532X7S2A475M ? >>> >>> [...] >> >> Since you stated 4.7 uF @ 100 V i looked in the medium voltage list, >> under 4.5mm x 3.2mm [EIA 1812] and there is at the bottom of the list. >> >> -60 % at 50 V. > > > But the graph stops at 50V while it's s'posed to go to 100V ... > Do you really want to see the cap drop by 80%? -- Thanks, Fred.
From: Joerg on 28 Mar 2010 17:11 Fred Bartoli wrote: > Joerg a �crit : >> JosephKK wrote: >>> On Sat, 27 Mar 2010 08:56:48 -0700, Joerg <invalid(a)invalid.invalid> >>> wrote: >>> >>>> John Devereux wrote: >>>>> Joerg <invalid(a)invalid.invalid> writes: >>>>> >>>>>> legg wrote: >>>>>>> On Fri, 26 Mar 2010 06:59:10 -0700, Joerg <invalid(a)invalid.invalid> >>>>>>> wrote: >>>>>>> >>>>>>>> legg wrote: >>>>>>>> And that's not telling anything about voltage tolerance. The temp >>>>>>>> curves are usually in the datasheets, voltage graphs aren't anymore >>>>>>>> :-) >>>>>>>> >>>>>>> The TDK graphing utility is really quite good. Perhaps you might >>>>>>> encourage this kind of data service by buying only those parts for >>>>>>> which info IS provided. >>>>>>> >>>>>>> TDK will even plot multiple selections on the same axis - just be >>>>>>> very >>>>>>> general about your initial selections - voltage, body size and maybe >>>>>>> tempco. >>>>>>> >>>>>>> http://www.tdk.co.jp/ccv/index.asp >>>>>>> >>>>>> -> "No results were found" :-( >>>>>> >>>>>> I could try over and over again to make it spit out a capacitance >>>>>> over >>>>>> voltage graph, on the client's nickel. Or just move on to another >>>>>> brand ... >>>>> Works fine for me - quite nice, I agree it should be in the datasheet. >>>>> >>>> Maybe I am doing something wrong with the search input fields. How >>>> do you get the capacitance versus voltage graph for the TDK >>>> capacitor with the part number C4532X7S2A475M ? >>>> >>>> [...] >>> >>> Since you stated 4.7 uF @ 100 V i looked in the medium voltage list, >>> under 4.5mm x 3.2mm [EIA 1812] and there is at the bottom of the list. >>> >>> -60 % at 50 V. >> >> >> But the graph stops at 50V while it's s'posed to go to 100V ... >> > > Do you really want to see the cap drop by 80%? > I want to know where it does. One reason for that is to be able to model overvoltage spikes somewhat properly. A cap that's spec'd at 100V ought to have graphs that go to 100V. Why don't they do that? From experience I can tell you that this would raise the hackles at agency testing. And that's never a good thing to happen :-) -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Tim Williams on 30 Mar 2010 00:44
"Don Klipstein" <don(a)manx.misty.com> wrote in message news:slrnhr2u17.idg.don(a)manx.misty.com... > "Electrolytic" makes an alarm bell go off in my head against > expectation of capacitance refusing to vary with voltage. > > Is there a reason for polymer to fix this for aluminum electrolytics? Tantalums are quite excellent (typically 10%, stable enough e.g. for long period timing), but they have a tendancy to explode. By removing the moist electrolyte from the capacitor, replacing it with a conductive organic polymer, the alpos get tantalum grade performance without the risk of incineration. Tim -- Deep Friar: a very philosophical monk. Website: http://webpages.charter.net/dawill/tmoranwms |