EEVblog Electronics Community Forum
Electronics => Repair => Topic started by: Faringdon on July 19, 2023, 08:04:46 am
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Hi,
We have an opto on a PCB which we believe is of the Sharp "PC357" family.
P357
https://uk.rs-online.com/web/p/optocouplers/8264684?cm_mmc=UK-PPC-DS3A-_-google-_-DSA_UK_EN_Displays+%26+Optoelectronics_Index-_-Optocouplers%7C+Products-_-DYNAMIC+SEARCH+ADS&matchtype=&dsa-1592138831419&cq_src=google_ads&cq_cmp=15904458467&cq_term=&cq_plac=&cq_net=g&cq_plt=gp&gclid=Cj0KCQjwk96lBhDHARIsAEKO4xaAvdlPVsiNkrnlzPJnbfOpRnNYW8enH4kkC8z3DiLcqd0WSUzyBIMaAr2-EALw_wcB&gclsrc=aw.ds
It is marked....
QUOTE...
S B8
357
D
....UNQUOTE
According to the above datasheet, this means the CTR could be either....
300-600%
200-600%
160-600%
80-600%
...from looking at page 5 of the datasheet.
Do you know which one it might be?
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Maybe TLP357 also very common opto?
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Page 2 tells you where "RANK MARK" is
Page 5 tells you what "rank mark" translates to CTR @ I.F = 5 mA
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Yes, thanks, but a Rank Mark of "D" corresponds to many different CTRs, as page 5 says
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Not many different CTRs, but the range between 80% and 600%.
If you want to know the CTR of your device you will need to measure it. Not difficult to do and does not require any elaborate setup or exotic equipment.
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Yes, thanks, but a Rank Mark of "D" corresponds to many different CTRs, as page 5 says
To the range of CTRs to be precise.
Parts are measured and marked per bin/rank to narrow down spread of CTR for your project. Relying on exact CTR value is bad practice. CTR drops with age and varies with temperature anyway..