SMT caps - ESR reading help.

[[email protected]]

I am repairing a camcorder ccd0tr75e and would like to now what
readings I sould get with an ESR meter for these small SMT caps.
For the 10uf 6volts I measure .48 and some at .88
For the 22uf 10volts I measure .18 and some at .62
As I don't have any newones on hand could someone please tell me what
ERS is acceptable.
Thanks
Jim

 

[[email protected]]

I am repairing a camcorder ccd0tr75e and would like to now what
readings I sould get with an ESR meter for these small SMT caps.
For the 10uf 6volts I measure .48 and some at .88
For the 22uf 10volts I measure .18 and some at .62
As I don't have any newones on hand could someone please tell me what
ERS is acceptable.
Thanks
Jim

= = = = = = = = = = = = = = = =


SMD = Surface Mount Device
SMT = Surface Mount Transistor

It appears you are dealing with SMD caps not SMT caps. The ESR
readings you specified are "normal". To doublecheck your findings,
with your specific ESR meter and brand of ESR meter, you can test a
small quantity of 10uf and 22uf caps in your parts bin to obtain an
"average"... they do not have to be SMD type, they can be radial,
axial and a variety of voltage ratings.

 

[[email protected]]

You can check out the "Hints" page for the Bob Parker meter:

http://members.ozemail.com.au/~bobpar/esrhints.htm

Here's his page:

http://members.ozemail.com.au/~bobpar/

Here's a chart for worst case cap values:

http://members.ozemail.com.au/~bobpar/2003esrchart.txt

from the "Hints" page.

BTW I've worked on a bunch of thoseSMD "fish" caps in those camcorders
and they definately stick out when they're bad.

Richard

 

[[email protected]]

Thanks for clarification on SMD and the websites;
I am dealing with caps and yes something is fishy when the camcorder is
on for about 5 minutes but there is no visual damage inside the boards,
therefore I need to rely on the measuments of ESR readings.
I have actually found 2 of the 10uf 16 volts to have 1.0 and 1.1 which
are the highest of the lot so I am suspecting them to be the smellyones
but I cannot turn camcorder on to check.
Is it okai to warm them up with the tip of the soldering iron and for
how many seconds? Thanks
JIM

 

[[email protected]]

Hmm 1.0 and 1.1 seem to be within the OK range. I just repaired a
control board for a Sony DVD player that had these caps on it. The ones
I replaced had readings more in the 16 and 18 range. BTW I got the
replacements from Mouser.

I heat the leads where they're pegged down to the boards and slowly
work them off. Be careful the traces on some boards will lift if you
get them too hot. Altho' I've never had that problem on Sony boards
only Daewoo. Low temp solder and micro low temp irons would help.
Anyone have a better way to remove these "fish" caps??

Richard

 

[David L. Jones]

I am repairing a camcorder ccd0tr75e and would like to now what
readings I sould get with an ESR meter for these small SMT caps.
For the 10uf 6volts I measure .48 and some at .88
For the 22uf 10volts I measure .18 and some at .62
As I don't have any newones on hand could someone please tell me what
ERS is acceptable.
Thanks
Jim

You can get very low ESR tantalum caps in addition to the "regular"
variety.
The 22uF 10V one for example might be in the order of 2ohms for a
normal one, while a low ESR one might be in the order of several
hundred milliohms. So for that cap I would say you have the low ESR
variety.
A 10uF 6V one would be higher than 2ohms for a normal type, so again I
think you have low ESR types.
Both I would consider to be perfectly acceptable values.

Dave