I can't really keep the gate voltage in the on-state. But I've decided on ye olde two-transistor flip-flop. Have to look for arrays now, to make it small. But my wife also has some other jobs planned, in the yard, involving a ladder and a bow saw and all that.
current into the gate.
But I ain't got the luxury of a continuous current :-)
ones
Needs
miniscule,
current into the gate.
As long as you want to keep the CONTEXT a big mystery, you're not gonna get a reasonable answer.
can
ones
Needs
miniscule,
bias current into the gate.
reasonable answer.
Not a mystery. I've mentioned several times in the thread that I cannot waste power. Also, if you sink current into the trigger pin that is dicey. While they do guarantee that the thing will trigger at a certain current they do not guarantee that it won't at 50% or so.
Anyhow, I'll do it discrete flip-flop style now because there does not seem to be any suitable device.
Can you make one with "high voltage" JFETs? Maybe you can find some with
60Vds (most are 30). Minimum turn on threshold may be too low, don't think you mentioned minimum supply requirement. Of course, the canonical structure would use a PFET, but you could substitute a PNP so you only need half the resistors, or something like that.MOS is similarly an option if you can find one with really high Vgs(max). Unlikely..
Tim
-- Deep Friar: a very philosophical monk. Website:
There are 1mm x 1mm 2-resistor networks. No leftovers.
Best regards, Spehro Pefhany
Those would be nice. But I am afraid they won't want anything smaller than 0402 in terms of pitch.
Well, I used two transistors as flip-flops. Works.
The min voltage can be as low as 10V, max just under 60V. There are no high voltage JFETs but lots of depletion mode MOSFETs. Only N-Channel though.
can
ones
Needs
miniscule,
bias current into the gate.
reasonable answer.
Typical Joerg ;-)
What's with the Outhouse Excuse style punctuation? ...Jim Thompson
Aren't two resistor 0402 (metric 1005) arrays (metric 1010) 1x1mm?
can
ones
Needs
miniscule,
bias current into the gate.
reasonable answer.
Fred is another Google Groups user.
Tim Williams a écrit :
MOSFETs with a gate zener clamp will take care of the 60V...
can
ones
Needs
miniscule,
bias current into the gate.
reasonable answer.
Not Outhouse Excuse, Google Gropes. Idiots insist on using both.
Not quite :-)
You need space in between and the landing area is supposed to be 1.3mm long plus spacing to the next part. Using many resistors is also an issue in some apps because they are only rated 50V. Tough this is not an aircraft project so we may be ok.
But he said, "There are 1mm x 1mm 2-resistor networks. No leftovers.", which is the point. Two-resistor 0402 arrays *are* 1mm x 1mm. No, I guess you can't put them on a 1mmx1mm board. ;-)
Depending on the circuit, voltage may not be an issue. You're being quite secretive so it's pretty hard to help with the details. OTOH, I often get specs like this. Then when things don't turn out as _they_ later decide they should, such complaints aren't uncommon. ;-)
Nothing secretive about this one. It has to go up to 60V and all this is used to turn off a rail when the uC says so. The same rail which also feeds this very uC :-)
But it's fixed, I just use a discrete flip-flop. Was just wondering whether anyone makes
I wanna know where (why?) you're getting 60V uCs. ;-)
1mm x 1mm is 0404 = 2x 0402 side-by-side.
Best regards, Spehro Pefhany
Here it is :-)
In my case the uC is, of course, behind a regulator. Along with a lot of other stuff off of some more regulators. Under certain conditions all this has to turn itself off. Overtemp and so on. Has to be really off, as in no supply voltage to anything.
[...]
Then they'd be shorted out ... bzzzt ... *PHUT* :-)
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