CTR of opto-coupler at low diode current (IF)?

Status
Not open for further replies.
E

eem2am

Banned
Joined
Jun 22, 2008
Messages
1,179
Helped
37
Reputation
74
Reaction score
24
Trophy points
1,318
Activity points
0
Hello,

Can i please confirm that even though the CNY17-2 opto-coupler has a stated CTR of 63% to 125%, .....this does not apply at all levels of diode current?

For example ,Figure 5, page 5 appears to show that the CTR of CNY17-2 is just 30% at a diode current (IF) of 500uA ?

So do you agree that at low diode currents, the stated "63% to 125%" CTR is meaningless?


CNY17-2 DATASHEET:
https://www.vishay.com/docs/83606/cny17.pdf
 
Last edited:

I don't disagree or disagree specifically, but every BJT has a
rolloff of hFE at low current and every LED has an output
efficiency curve that peaks as well.

I expect if you read the fine print, that CTR is spec'd over a
range that makes them look good, not necessarily the range
where you would like to use it.
 
Reactions: eem2am

    E

    eem2am

    Points: 2
    Helpful Answer Positive Rating
Status
Not open for further replies.

Similar threads

Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…