|
|
|
|
|||||||
| Components and Circuits For discussions about component types, alternatives and availability, circuit configurations and modifications etc. Discussions here should be of a general nature and not about specific sets. |
 |
|
|
Thread Tools |
27th Feb 2024, 6:58 pm
|
#1 |
|
Nonode
Join Date: Dec 2012
Location: Stockport, Greater Manchester, UK.
Posts: 2,122
|
Small wound inductors in SMPS
What value are these RFCs, pulled from the SMPS in a scrap set-top box, likely to be? I don't recognise the marking (E or F) 97799 (8 or 9)
__________________
- Julian It's good here 
|
|
|
|
27th Feb 2024, 11:09 pm
|
#2 |
|
Nonode
Join Date: Oct 2010
Location: Tintinara, South Australia, Australia
Posts: 2,346
|
Re: Small wound inductors in SMPS
Likely to be a house part #.
Only way to know the value will be to measure it |
|
|
|
|
27th Feb 2024, 11:29 pm
|
#3 |
|
Heptode
Join Date: Oct 2009
Location: Melbourne Australia
Posts: 903
|
Re: Small wound inductors in SMPS
I'd anticipate an inductance around 22 to 100uH based on similar (Panasonic ELCOBD 22uH with 24T) that I have.
Strangely, I use my batch to make smaller inductances (up to 4uH) for use in audio valve amplifier current feedback circuits. |
|
|
|
28th Feb 2024, 1:05 am
|
#4 |
|
Dekatron
Join Date: Dec 2007
Location: Haarlem, Netherlands
Posts: 4,207
|
Re: Small wound inductors in SMPS
The marking looks similar to Toko (date?) codes.
|
|
|
|
|
28th Feb 2024, 12:22 pm
|
#5 |
|
Moderator
Join Date: Jun 2003
Location: Oxford, UK
Posts: 28,001
|
Re: Small wound inductors in SMPS
One of the cheap Chinese component analysers should be able to measure the inductance.
|
|
|
|
|
28th Feb 2024, 2:36 pm
|
#6 | |
|
Nonode
Join Date: Dec 2012
Location: Stockport, Greater Manchester, UK.
Posts: 2,122
|
Re: Small wound inductors in SMPS
Quote:
__________________
- Julian It's good here
|
|
|
|
|
|
28th Feb 2024, 2:49 pm
|
#7 |
|
Moderator
Join Date: Jun 2003
Location: Oxford, UK
Posts: 28,001
|
Re: Small wound inductors in SMPS
Measuring lots of them in series was a good idea.
|
|
|
|
|
28th Feb 2024, 3:01 pm
|
#8 |
|
Dekatron
Join Date: Apr 2012
Location: Wiltshire, UK.
Posts: 14,015
|
Re: Small wound inductors in SMPS
I wonder what use they would be? Only thing I can think of is wiring them in series with loudspeaker leads [with associated capacitors to ground] to prevent RFI pickup.
__________________
I'm the Operator of my Pocket Calculator. -Kraftwerk. |
|
|
|
|
28th Feb 2024, 5:04 pm
|
#9 |
|
Moderator
Join Date: Jun 2003
Location: Oxford, UK
Posts: 28,001
|
Re: Small wound inductors in SMPS
You could use them to wind new inductors.
|
|
|
|
|
28th Feb 2024, 9:10 pm
|
#10 |
|
Nonode
Join Date: Oct 2008
Location: Warsaw, Poland and Cambridge, UK
Posts: 2,682
|
Re: Small wound inductors in SMPS
Those inductors of about 25 microhenries are the right sort of value for making switch-mode boost converters, or other switch-mode power supplies. I've got a drawer full of similar values here which get used for that.
Chris
__________________
What's going on in the workshop? http://martin-jones.com/ |
|
|
|
|
28th Feb 2024, 11:24 pm
|
#11 | |
|
Heptode
Join Date: Oct 2009
Location: Melbourne Australia
Posts: 903
|
Re: Small wound inductors in SMPS
Quote:
They are often located in a CLC configuration, where the first C takes the high ripple brunt from a rectifier, and then the LC attempts to suppress remnant high frequency disturbances as well as switching frequency ripple. The wire in my likely equivalent 22uH inductor is nearly 0.50mm diameter, so perhaps suited for up to about 0.5A, although datasheet rated for over an amp. Last edited by trobbins; 28th Feb 2024 at 11:32 pm. |
|
|
|
|
|
29th Feb 2024, 5:04 pm
|
#12 |
|
Nonode
Join Date: Dec 2012
Location: Stockport, Greater Manchester, UK.
Posts: 2,122
|
Re: Small wound inductors in SMPS
Yes, 25µH, I'm not so good at dividing by 1000
__________________
- Julian It's good here
|
|
|
|
