On Wed, 25 May 2011 22:45:38 -0700, Robert Baer
wrote:
Ian Field wrote:
"John Larkin" wrote in message
...
On Mon, 23 May 2011 16:35:57 -0700, Tim Wescott
wrote:
On 05/23/2011 03:52 PM, Jim Thompson wrote:
Is this the correct pin out for a 2N7000...
http://analog-innovations.com/SED/2N...ak_Pin_Out.pdf
My expectations, from bipolar's, would be, facing the flat, leads
down. left-to-right...
D-G-S
My expectations, from browsing many data sheets, is that the pinout of
any three-terminal device is pretty well standardized:
Pin 1: random
Pin 2: random
Pin 3: random
Even the pin numbers can be random. I've seen all possible
permutations of 1-2-3 on various SOT23 parts. We use the "Motorola"
convention, and force any parts that we use into it.
So, maybe the 2N7000 is a little randomer than you thought -- it's still
normal.
All you need is a ohmmeter to discover/verify the pinout.
What I use is a Steinel continuity checker, it has a 12V keyfob battery & 2
LEDs. Stick the + probe on the drain and the - on source, usually stray
charge will cause enough conduction to make the LED glow, breifly moving
the - probe to gate discharges it then back to source and no light means
good MOSFET, move the positive to the gate to charge it and it conducts
again.
With unknown leadouts its relatively simple to identify the gate as there's
no continuity to either other terminal either way round. Which way round the
body diode is tells you half of what else you need to know.
That is an extremely good and reliable way to destroy the gate...
I've done a lot of playing with 2N7000s with floating gates.
ftp://jjlarkin.lmi.net/2N7000.jpg
There are all sorts of fun things you can do with a 2N7000, a battery,
a resistor, and an LED. I've never managed to blow a gate, even using
body charge to tweak the floating gate bias. They seem to be pretty
tough. The gates seem to leak not very many electrons per second.
I've been meaning to test some various mosfets to gate-voltage
destruction. I get the impression they can usually stand a lot more
than the datasheets suggest.
Does a 2N7000 typically have a gate zener?
John