how to calculate the Current transfer ratio of Optocoupler

[nareshgtr]

current transfer ratio

hi guys,
I am using FOD817 optocoupler in my design. As per the data sheet, the current transfer ratio of FOD817A is 80-160. My query is how to measure the CTR and how to fix the CTR.

Regards
V. Naresh Kumar
Advay Solutions Pvt. Ltd

 

[FvM]

current transfer ratio optocoupler

You can measure (output current/input current) but not fix it. In circuit design, any value within the said range must be expected.

 

[hakeen]

optocoupler calculation

It is just ratio of Ic/If*100%. You can measure it in saturated mode or in linear mode, depending on your appliaction. You differentiate these with the help of VCE value in test conditions.

E.g. HCPL-817-00BE has 80-160% CTR at VCE=5V, If=5mA.