On Mon, 1 Jul 2019 at 03:31, doug metzler wrote: > > Correct, fat finger. The actual part number is IRLR3636PbF. > That's the one that I provided a datasheet link to so we are both talking about the same part. Because of my "it's been my understanding" statement - I've tried to switch > 24V with logic level fets in the past and it hasn't worked as I expected. > My solution was to use a transistor to raise the gate voltage. I'm sur= e > Russell is correct that I'm not reading the datasheet carefully enough. > > Q1 - What is the switching repetition rate? Q2 - How long on and how long off? Q3 - Is there any reason apart from device dissipation to require rapid turn on and off? Q4 - What are worst case ambient conditions? (eg not in Erebus crater or .... ?)(As happens ...) *Dante II volcano robot * Q5 - Is the load inductive or has it an inductive component - or might it have? I feel that there is something 'generally wrong' here. It partly depends on what "it hasn't worked' means. At the sort of currents and voltages involved I'd expect a very basic gate drive circuit would suffice, unless there is an exceptional requirement for rapid turn on or off. eg at 24V and 16A peak (which may or may not occur at turn on or off) if you dissipated all of the energy in the FET (which you won't) during switching transition you;d get 24 x 16 =3D~ 400 Watts or 0.4 mJ/microsecond off transition time. Look at datasheet page 5 figs 13 14 15. Allowed "avalanche energy" is far in excess of what you should need with a simple driver. If you did need higher current drive then more current (but no more voltage) can be obtained with two jellybean transistors acting as dual emitter followers. More on that if required. rUSSELL > > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .