Here is a link <http://www.infineon.com/dgdl/Infineon-Application_Note_Applications_for_Depletion_MOSFETs-AN-v01_00-EN.pdf?fileId=5546d4624cb7f111014cd63d1a197d94> to a paper about using a depletion mode MOSFET for the same purpose. It gives this equation for calculating the resistor value, which I assume would be the same for all depletion mode MOSFETS (!?):
<https://lh3.googleusercontent.com/-BIZNnjZU_6Y/WOgFjAlbUJI/AAAAAAAAAi4/6FaT3NlNgJ0hFwLOnQChLGzvyur6iVq-QCLcB/s1600/Capture.JPG> VGS(th) is the gate threshold voltage of the MOSFET, IDSS is the on current at VGS = 0 V and ID is the required current. There are plenty of these around with suitable voltage characteristics. -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To post to this group, send an email to neonixie-l@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/c02f17e0-a13b-4095-b2a0-d17fd8bbb11d%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
