And there is the good old negistor:

	http://jlnlabs.imars.com/cnr/negosc.htm


On 9 Jan 2006 at 23:28, Richard Prosser wrote:

> You can use a bipolar "=FCpside down"with the collector & emitter reverse=
d.
> This results in a transistor with low beta - but I'm not sure if it is
> less than 1.
> =

> I have used this arrangement in the past to reduce the sensitivity of
> a "SCR" type circuit made up of an NPN and a PNP transistor. Otherwise
> the leakage current through the input device can be enough to trigger
> the output device at high temperatures.
> =

> Makes people scratch their heads when they check the circuit however.
> =

> RP
> =




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