Hi folks I'm really new with electronics. Doing a massive project for a retro computer system and, as a prong of this project I'm attempting to locate a modern equivalent of the board components. Enter the tantalum capacitor. Having gone to digikey, mouser, and newark none of them seem to have the item I'm looking for in stock. What are the rules about alternate values? The tantalum cap I'm looking for, according to the service manual, has the following rating: 1uf,10v, +-20%. The DIP style cap that the board uses isn't in stock anywhere so would I be able to substitute this cap for 1uf, 20v, +-20%? Thanks, Daniel
Capacitor rules
Started by ●March 1, 2023
Reply by ●March 1, 20232023-03-01
On 2023-03-01 09:06, Daniel wrote:> Hi folks I'm really new with electronics. Doing a massive project for a > retro computer system and, as a prong of this project I'm attempting to > locate a modern equivalent of the board components. Enter the tantalum > capacitor. Having gone to digikey, mouser, and newark none of them seem > to have the item I'm looking for in stock. > > What are the rules about alternate values? The tantalum cap I'm looking > for, according to the service manual, has the following rating: > > 1uf,10v, +-20%. > > The DIP style cap that the board uses isn't in stock anywhere so would I > be able to substitute this cap for 1uf, 20v, +-20%? > > Thanks, > > Daniel >Going up in voltage rating is fine. There might possibly be an issue if the effective series resistance (ESR) is higher, but all solid tants have highish ESR anyway, so it's unlikely to make a noticeable difference. (Polymer tants are a different animal.) Cheers Phil Hobbs
Reply by ●March 1, 20232023-03-01
On 2023-03-01, Daniel <me@sc1f1dan.com> wrote:> Hi folks I'm really new with electronics. Doing a massive project for a > retro computer system and, as a prong of this project I'm attempting to > locate a modern equivalent of the board components. Enter the tantalum > capacitor. Having gone to digikey, mouser, and newark none of them seem > to have the item I'm looking for in stock. > > What are the rules about alternate values?lower percentage good, higher voltage good. same or close capacitance good, sometimes more capacitance is good.> The tantalum cap I'm looking > for, according to the service manual, has the following rating: > > 1uf,10v, +-20%. > > The DIP style cap that the board uses isn't in stock anywhere so would I > be able to substitute this cap for 1uf, 20v, +-20%?DIP: I guessing you mean radial pins. With tantalum going up in voltage leads to improved reliability if this is a 5V or 8V supply decoupling capacitor the 20V part is much better suited. On the other hand inexpensive 1uF ceramic capacitors are now available and might be an even better substitute (even better reliability), but that depends mostly on the power supply being able to start with the reduced series resistance presented by the ceramic parts. -- Jasen. pǝsɹǝʌǝɹ sʇɥƃᴉɹ ll∀
Reply by ●March 1, 20232023-03-01
On 2023-03-01 19:17, Jasen Betts wrote:> On 2023-03-01, Daniel <me@sc1f1dan.com> wrote: >> Hi folks I'm really new with electronics. Doing a massive project for a >> retro computer system and, as a prong of this project I'm attempting to >> locate a modern equivalent of the board components. Enter the tantalum >> capacitor. Having gone to digikey, mouser, and newark none of them seem >> to have the item I'm looking for in stock. >> >> What are the rules about alternate values? > > lower percentage good, higher voltage good. > same or close capacitance good, > sometimes more capacitance is good. > >> The tantalum cap I'm looking >> for, according to the service manual, has the following rating: >> >> 1uf,10v, +-20%. >> >> The DIP style cap that the board uses isn't in stock anywhere so would I >> be able to substitute this cap for 1uf, 20v, +-20%? > > DIP: I guessing you mean radial pins.BITD you could get tants with actual 0.2 inch, 4-pin DIP patterns. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
Reply by ●March 1, 20232023-03-01
On 2023-03-01 19:54, Phil Hobbs wrote:> On 2023-03-01 19:17, Jasen Betts wrote: >> On 2023-03-01, Daniel <me@sc1f1dan.com> wrote: >>> Hi folks I'm really new with electronics. Doing a massive project for a >>> retro computer system and, as a prong of this project I'm attempting to >>> locate a modern equivalent of the board components. Enter the tantalum >>> capacitor. Having gone to digikey, mouser, and newark none of them seem >>> to have the item I'm looking for in stock. >>> >>> What are the rules about alternate values? >> >> lower percentage good, higher voltage good. >> same or close capacitance good, >> sometimes more capacitance is good. >> >>> The tantalum cap I'm looking >>> for, according to the service manual, has the following rating: >>> >>> 1uf,10v, +-20%. >>> >>> The DIP style cap that the board uses isn't in stock anywhere so would I >>> be able to substitute this cap for 1uf, 20v, +-20%? >> >> DIP: I guessing you mean radial pins. > > BITD you could get tants with actual0.3>inch, 4-pin DIP patterns. > > Cheers > > Phil Hobbs >-- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
Reply by ●March 13, 20232023-03-13
On 01/03/2023 9:06:01 a.m., Daniel wrote:> 1uf,10v, +-20%.Digikey has dozens of equivalent part numbers in Through hole 1μF Tantalum 10V or more, 20% or less and millions of caps , so try again. There are other parameters for reliability and size. but ESR is not one of them. These all tend to be OK like low ESR aluminum types with ESR*C product less than or equal to 10 microseconds. This is well above the audio bandwidth. f=0.44/RC but we have no way of knowing how it is used. 1μF,20v, +-10%. < I suggest but if it matters you can also search with filters for; Price Series Package Product Status Capacitance Tolerance Voltage - Rated Type ESR (Equivalent Series Resistance) Operating Temperature Lifetime @ Temp. Mounting Type Package / Case Size / Dimension Height - Seated (Max) Lead Spacing Manufacturer Size Code Ratings Features Failure Rate
