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From: Jeff Liebermann on 10 May 2010 17:42 On Mon, 10 May 2010 13:32:47 -0700 (PDT), saber850 <saber850(a)yahoo.com> wrote: >PCB Designation Farads (�F) Voltage (V) Temp (C) Length (mm) >Potential Length (mm) Diameter (mm) Lead Spacing (Board) (mm) Mouser >Replacement Mouser Replacement URL >C105 150 450 105 41 45 20 7 661-EKMQ451VN151MP40 >http://www.mouser.com/Search/ProductDetail.aspx?R=EKMQ451VN151MP40Svirtualkey66100000virtualkey661-EKMQ451VN151MP40 You probably do NOT need to replace the big 150uF/450V capacitor. It's not the high voltage low ripple current capacitors that fail. It's the low voltage, but high ripple current filter caps that get hot and blow up. >C107 47 50 105 11 24 5 5 667-ECA-1HHG470 >http://www.mouser.com/Search/ProductDetail.aspx?R=ECA-1HHG470virtualkey66720000virtualkey667-ECA-1HHG470 Tolerable. It's not a low ESR type, but it's low enough to work. >C301 680 25 105 17 22 10 5 667-EEU-FC1E681 >http://www.mouser.com/Search/ProductDetail.aspx?R=EEU-FC1E681virtualkey66720000virtualkey667-EEU-FC1E681 >C302 680 25 105 17 22 10 5 667-EEU-FC1E681 >http://www.mouser.com/Search/ProductDetail.aspx?R=EEU-FC1E681virtualkey66720000virtualkey667-EEU-FC1E681 It's low-ESR (although the data sheet doesn't clearly show this) so it will work. >C110 820 25 105 22 24 10 5 598-361R821M025EG0E >http://www.mouser.com/Search/ProductDetail.aspx?R=361R821M025EG0Evirtualkey59850000virtualkey598-361R821M025EG0E >C111 820 25 105 22 24 10 5 598-361R821M025EG0E >http://www.mouser.com/Search/ProductDetail.aspx?R=361R821M025EG0Evirtualkey59850000virtualkey598-361R821M025EG0E Also low-ESR and good quality cap. No problems. >C112 330 25 105 14 24 10 5 667-EEU-FC1E331 >http://www.mouser.com/Search/ProductDetail.aspx?R=EEU-FC1E331virtualkey66720000virtualkey667-EEU-FC1E331 Looks generally ok. I'll leave it to you to determine if the case sizes and lead spacing are the same as the originals. Neither is particularly critical as there is usually plenty of room. One suggestion is to use the next higher voltage rating capacitor. The 50v cap will probably remain 50v, but the 25v caps should be replaced with 35v caps. They last longer, have a lower ESR, and aren't that much larger. -- Jeff Liebermann jeffl(a)cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
From: saber850 on 10 May 2010 19:53 On May 10, 5:42 pm, Jeff Liebermann <je...(a)cruzio.com> wrote: > On Mon, 10 May 2010 13:32:47 -0700 (PDT), saber850 > > <saber...(a)yahoo.com> wrote: > >PCB Designation Farads (µF) Voltage (V) Temp (C) Length (mm) > >Potential Length (mm) Diameter (mm) Lead Spacing (Board) (mm) Mouser > >Replacement Mouser Replacement URL > >C105 150 450 105 41 45 20 7 661-EKMQ451VN151MP40 > >http://www.mouser.com/Search/ProductDetail.aspx?R=EKMQ451VN151MP40Svi.... > > You probably do NOT need to replace the big 150uF/450V capacitor. It's > not the high voltage low ripple current capacitors that fail. It's the > low voltage, but high ripple current filter caps that get hot and blow > up. > > >C107 47 50 105 11 24 5 5 667-ECA-1HHG470 > >http://www.mouser.com/Search/ProductDetail.aspx?R=ECA-1HHG470virtualk.... > > Tolerable. It's not a low ESR type, but it's low enough to work. > > >C301 680 25 105 17 22 10 5 667-EEU-FC1E681 > >http://www.mouser.com/Search/ProductDetail.aspx?R=EEU-FC1E681virtualk.... > >C302 680 25 105 17 22 10 5 667-EEU-FC1E681 > >http://www.mouser.com/Search/ProductDetail.aspx?R=EEU-FC1E681virtualk.... > > It's low-ESR (although the data sheet doesn't clearly show this) so it > will work. > > >C110 820 25 105 22 24 10 5 598-361R821M025EG0E > >http://www.mouser.com/Search/ProductDetail.aspx?R=361R821M025EG0Evirt.... > >C111 820 25 105 22 24 10 5 598-361R821M025EG0E > >http://www.mouser.com/Search/ProductDetail.aspx?R=361R821M025EG0Evirt.... > > Also low-ESR and good quality cap. No problems. > > >C112 330 25 105 14 24 10 5 667-EEU-FC1E331 > >http://www.mouser.com/Search/ProductDetail.aspx?R=EEU-FC1E331virtualk.... > > Looks generally ok. > > I'll leave it to you to determine if the case sizes and lead spacing > are the same as the originals. Neither is particularly critical as > there is usually plenty of room. One suggestion is to use the next > higher voltage rating capacitor. The 50v cap will probably remain > 50v, but the 25v caps should be replaced with 35v caps. They last > longer, have a lower ESR, and aren't that much larger. > > -- > Jeff Liebermann je...(a)cruzio.com > 150 Felker St #D http://www.LearnByDestroying.com > Santa Cruz CA 95060http://802.11junk.com > Skype: JeffLiebermann AE6KS 831-336-2558 Thanks for reviewing & the feedback. I'm glad I don't need to change the large cap. I'm looking for a cap w/ a lower ESR for the C107 cap (47uF, 50V). I don't see 'ESR' in the data sheet. What do I look for? Would this one be better: http://www.mouser.com/ProductDetail/Panasonic/EEU-EB1H470S/?qs=sGAEpiMZZMtZ1n0r9vR22ZOBEZetCii%252b7xHyu04R92c%3d ? Most of these caps were near, if not at, the physical size limit. All of the 25V caps have <= 2mm of space to a neighboring component, and in 2 cases, it's another cap (so only one could be bigger). So there isn't much room for these (one will actually be a very tight fit as is).
From: Jeff Liebermann on 11 May 2010 01:51 On Mon, 10 May 2010 16:53:58 -0700 (PDT), saber850 <saber850(a)yahoo.com> wrote: >I'm looking for a cap w/ a lower ESR for the C107 cap (47uF, 50V). I >don't see 'ESR' in the data sheet. What do I look for? If the ESR isn't specified, then look for loss tangent or dissipation factor (tan sigma). Dissipation factor does NOT directly translate to ESR, but it's proportional when comparing caps at the same frequency. The lower number is better. <http://en.wikipedia.org/wiki/Dissipation_factor> ESR = DF / (Pi * freq * C) You can calculate ESR, but there's a problem. The dissipation of the dielectric varies with frequency where the ESR number specified is only valid at the test frequency. When DF or loss tangents are specified, it's sometimes at 120Hz, where the capacitor is intended for a linear type AC power supply filter. When ESR is specified, it's usually at 100KHz which implies that it's for a switching power supply. The Panasonic EEU-FC series you included specifies ESR as impedance at 100KHz. For comparison, a 47uF/50v Panasonic EEU-FC series cap as below shows 0.6 ohms max ESR. >Would this >one be better: >http://www.mouser.com/ProductDetail/Panasonic/EEU-EB1H470S/?qs=sGAEpiMZZMtZ1n0r9vR22ZOBEZetCii%252b7xHyu04R92c%3d Well, for 47uf/50v the Panasonic EEU shows 0.15 DF. The previous Chemicon KMQ series cap shows 0.12 DF. I would call the Chemicon capacitor slightly better. Unfortunately, the sanity check doesn't quite work. The ESR at 100KHz grinds out to: ESR = DF / (2Pi * freq * C) ESR = 0.15 / (6.28 * 0.1*10^6 * 47*10^-6) ESR = 0.15 / 29.8 = 0.0005 which is about 1000 times too small to be for real. When my brain recovers from this cold or flu, I'll try to figure out what I've done wrong. (I hate it when that happens). >Most of these caps were near, if not at, the physical size limit. All >of the 25V caps have <= 2mm of space to a neighboring component, and >in 2 cases, it's another cap (so only one could be bigger). So there >isn't much room for these (one will actually be a very tight fit as >is). Looking at the photos of the board, some of the caps look fairly tight. I guess you should probably leave it at 25V. -- Jeff Liebermann jeffl(a)cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
From: saber850 on 11 May 2010 08:32 On May 11, 1:51 am, Jeff Liebermann <je...(a)cruzio.com> wrote: > On Mon, 10 May 2010 16:53:58 -0700 (PDT), saber850 > > <saber...(a)yahoo.com> wrote: > >I'm looking for a cap w/ a lower ESR for the C107 cap (47uF, 50V). I > >don't see 'ESR' in the data sheet. What do I look for? > > If the ESR isn't specified, then look for loss tangent or dissipation > factor (tan sigma). Dissipation factor does NOT directly translate to > ESR, but it's proportional when comparing caps at the same frequency. > The lower number is better. > <http://en.wikipedia.org/wiki/Dissipation_factor> > ESR = DF / (Pi * freq * C) > You can calculate ESR, but there's a problem. The dissipation of the > dielectric varies with frequency where the ESR number specified is > only valid at the test frequency. When DF or loss tangents are > specified, it's sometimes at 120Hz, where the capacitor is intended > for a linear type AC power supply filter. When ESR is specified, it's > usually at 100KHz which implies that it's for a switching power > supply. The Panasonic EEU-FC series you included specifies ESR as > impedance at 100KHz. For comparison, a 47uF/50v Panasonic EEU-FC > series cap as below shows 0.6 ohms max ESR. > > >Would this > >one be better: > >http://www.mouser.com/ProductDetail/Panasonic/EEU-EB1H470S/?qs=sGAEpi.... > > Well, for 47uf/50v the Panasonic EEU shows 0.15 DF. > The previous Chemicon KMQ series cap shows 0.12 DF. > I would call the Chemicon capacitor slightly better. > > Unfortunately, the sanity check doesn't quite work. The ESR at 100KHz > grinds out to: > ESR = DF / (2Pi * freq * C) > ESR = 0.15 / (6.28 * 0.1*10^6 * 47*10^-6) > ESR = 0.15 / 29.8 = 0.0005 > which is about 1000 times too small to be for real. When my brain > recovers from this cold or flu, I'll try to figure out what I've done > wrong. (I hate it when that happens). > > >Most of these caps were near, if not at, the physical size limit. All > >of the 25V caps have <= 2mm of space to a neighboring component, and > >in 2 cases, it's another cap (so only one could be bigger). So there > >isn't much room for these (one will actually be a very tight fit as > >is). > > Looking at the photos of the board, some of the caps look fairly > tight. I guess you should probably leave it at 25V. > > -- > Jeff Liebermann je...(a)cruzio.com > 150 Felker St #D http://www.LearnByDestroying.com > Santa Cruz CA 95060http://802.11junk.com > Skype: JeffLiebermann AE6KS 831-336-2558 Thanks for all the info. Which tool(s) should I consider getting to help w/ the desoldering? I'm guessing there's something to help get the solder out of the PCB hole. Braided copper? Solder sucker?
From: bz on 11 May 2010 08:09
saber850 <saber850(a)yahoo.com> wrote in news:16a07027-3ed3-420e-ba09-9374f670316d(a)37g2000yqm.googlegroups.com: > On May 10, 5:42�pm, Jeff Liebermann <je...(a)cruzio.com> wrote: >> On Mon, 10 May 2010 13:32:47 -0700 (PDT), saber850 >> >> <saber...(a)yahoo.com> wrote: >> >PCB Designation � � Farads (�F) � �Voltage (V) � � Temp (C > ) � � � �Length (mm) >> >Potential Length (mm) � � � Diameter (mm) � Lead Spacing (Board) > (mm) � � � Mouser >> >Replacement Mouser �Replacement URL >> >C105 � � � �150 � � 450 � � 105 � � 41 � � �45 > � � �20 � � �7 � � � 661-EKMQ451VN151MP40 >> >http://www.mouser.com/Search/ProductDetail.aspx?R=EKMQ451VN151MP40Svi. > .. >> >> You probably do NOT need to replace the big 150uF/450V capacitor. It's >> not the high voltage low ripple current capacitors that fail. It's the >> low voltage, but high ripple current filter caps that get hot and blow >> up. >> >> >C107 � � � �47 � � �50 � � �105 � � 11 � � > �24 � � �5 � � � 5 � � � 667-ECA-1HHG470 >> >http://www.mouser.com/Search/ProductDetail.aspx?R=ECA-1HHG470virtualk. > .. >> >> Tolerable. �It's not a low ESR type, but it's low enough to work. >> >> >C301 � � � �680 � � 25 � � �105 � � 17 � � � > 22 � � �10 � � �5 � � � 667-EEU-FC1E681 >> >http://www.mouser.com/Search/ProductDetail.aspx?R=EEU-FC1E681virtualk. > .. >> >C302 � � � �680 � � 25 � � �105 � � 17 � � � > 22 � � �10 � � �5 � � � 667-EEU-FC1E681 >> >http://www.mouser.com/Search/ProductDetail.aspx?R=EEU-FC1E681virtualk. > .. >> >> It's low-ESR (although the data sheet doesn't clearly show this) so it >> will work. >> >> >C110 � � � �820 � � 25 � � �105 � � 22 � � � > 24 � � �10 � � �5 � � � 598-361R821M025EG0E >> >http://www.mouser.com/Search/ProductDetail.aspx?R=361R821M025EG0Evirt. > .. >> >C111 � � � �820 � � 25 � � �105 � � 22 � � � > 24 � � �10 � � �5 � � � 598-361R821M025EG0E >> >http://www.mouser.com/Search/ProductDetail.aspx?R=361R821M025EG0Evirt. > .. >> >> Also low-ESR and good quality cap. �No problems. >> >> >C112 � � � �330 � � 25 � � �105 � � 14 � � � > 24 � � �10 � � �5 � � � 667-EEU-FC1E331 >> >http://www.mouser.com/Search/ProductDetail.aspx?R=EEU-FC1E331virtualk. > .. >> >> Looks generally ok. >> >> I'll leave it to you to determine if the case sizes and lead spacing >> are the same as the originals. �Neither is particularly critical as >> there is usually plenty of room. �One suggestion is to use the next >> higher voltage rating capacitor. �The 50v cap will probably remain >> 50v, but the 25v caps should be replaced with 35v caps. �They last >> longer, have a lower ESR, and aren't that much larger. >> >> -- >> Jeff Liebermann � � je...(a)cruzio.com >> 150 Felker St #D � �http://www.LearnByDestroying.com >> Santa Cruz CA 95060http://802.11junk.com >> Skype: JeffLiebermann � � AE6KS � �831-336-2558 > > Thanks for reviewing & the feedback. I'm glad I don't need to change > the large cap. > > I'm looking for a cap w/ a lower ESR for the C107 cap (47uF, 50V). I > don't see 'ESR' in the data sheet. What do I look for? Would this > one be better: > http://www.mouser.com/ProductDetail/Panasonic/EEU-EB1H470S/?qs=sGAEpiMZZM > tZ1n0r9vR22ZOBEZetCii%252b7xHyu04R92c%3d ? > > Most of these caps were near, if not at, the physical size limit. All > of the 25V caps have <= 2mm of space to a neighboring component, and > in 2 cases, it's another cap (so only one could be bigger). So there > isn't much room for these (one will actually be a very tight fit as > is). > ESR Equivalent Series Resistance http://wiki.xtronics.com/index.php/Capacitors_and_ESR ESR is usually NOT 'important' on new capacitors. One 'common' failure mode for electrolytic capacitors in an increase in ESR, especially in caps that have defective designs. http://www.badcaps.net/pages.php?vid=4 -- bz 73 de N5BZ k please pardon my infinite ignorance, the set-of-things-I-do-not-know is an infinite set. |