Hello,
Figure 5, page 3, of the following DALI application note (AN1465) shows optos being used to isolate both TX and RX DALI signals….
AN1465 Application note:
https://ww1.microchip.com/downloads/en/AppNotes/01465A.pdf
Though surely, the TX opto should be a TCLT1009 (CTR of TCLT1009 = 300%) and not a TCLT1000 (CTR of TCLT1000 = 50%)?
Also, surely the RX opto should be a TCLT1000, which it indeed is.
The reason that the RX opto should be a TCLT1000 is because it has a lower capacitance seen at its emitter pin which means the rise time of the emitter can be quicker. Do you agree?
TCLT100X opto datasheet:
https://www.vishay.com/docs/83515/tclt1000.pdf
Figure 5, page 3, of the following DALI application note (AN1465) shows optos being used to isolate both TX and RX DALI signals….
![cheesy.gif](https://www.eevblog.com/forum/Smileys/default/cheesy.gif)
AN1465 Application note:
https://ww1.microchip.com/downloads/en/AppNotes/01465A.pdf
Though surely, the TX opto should be a TCLT1009 (CTR of TCLT1009 = 300%) and not a TCLT1000 (CTR of TCLT1000 = 50%)?
![confused0024.gif](https://www.eevblog.com/forum/Smileys/default/confused0024.gif)
Also, surely the RX opto should be a TCLT1000, which it indeed is.
![clap.gif](https://www.eevblog.com/forum/Smileys/default/clap.gif)
The reason that the RX opto should be a TCLT1000 is because it has a lower capacitance seen at its emitter pin which means the rise time of the emitter can be quicker. Do you agree?
![confused0024.gif](https://www.eevblog.com/forum/Smileys/default/confused0024.gif)
TCLT100X opto datasheet:
https://www.vishay.com/docs/83515/tclt1000.pdf