Electronics > Projects, Designs, and Technical Stuff
Searching for an optocoupler with MOSFET output stage
(1/3) > >>
Lupin III.:
I'm looking for an optocoupler that has a MOSFET output stage and not the usual bipolar output transistor. I have an analog pin on a chip that I want to pull really close to ground (via an isolated signal), which means that the saturation voltage of a bipolar transistor is already too high. The current will be very low (<1mA), so the internal resistance doesn't matter. Switching speed isn't an issue either. As long as an about 1kHz square wave can get through it's fine. I can't really find such a component that's also easily available and rather cheap (~1€/piece would be nice since I need multiple of them).

Has anyone got any suggestions?
Wimberleytech:
The physics of a bipolar junction transistor make it very amenable to use as an opto-coupler...MOSFET device physics does not.  Could an opto be fabricated in a process that has both MOS and bipolar (e.g., BiCMOS)?  Yes, of course, but it would be more expensive and why?  I rather doubt one exists.
up8051:
MOUSER:
 All Products => Optoelectronics => Optocouplers / Photocouplers => MOSFET Output Optocouplers
Wimberleytech:

--- Quote from: up8051 on January 06, 2020, 05:00:16 pm ---MOUSER:
 All Products => Optoelectronics => Optocouplers / Photocouplers => MOSFET Output Optocouplers

--- End quote ---

Well, shut my mouth.  I have been schooled...lol!
Looking at the datasheet, it appears that they just put an output stage on a more-or-less conventional opto circuit.
oPossum:
There are even depletion mode MOSFET optos that are normally closed.
Navigation
Message Index
Next page
There was an error while thanking
Thanking...

Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod