JFET as unijunction transistor?

[Salmon Egg]

It strikes me that a JFET, junction field effect transistor, has the same
basic structure as a unijunction transistor. Has anyone here tried using a
JFET as a unijunction transistor? How has it worked out? What is a good
cheap type to get for the purpose?

Bill

-- Fermez le Bush

 

[ian field]

It strikes me that a JFET, junction field effect transistor, has the same
basic structure as a unijunction transistor. Has anyone here tried using a
JFET as a unijunction transistor? How has it worked out? What is a good
cheap type to get for the purpose?

Bill

-- Fermez le Bush

With only 2 transistors (1 NPN & 1 PNP) you can simulate a programmable
unijunction transistor (PUT) - simply connect the base of each transistor to
the collector of the other, the emitters are the anode and cathode.
Technically since you have access to both C/B joins the device you have
created is a silicon controlled switch (SCS) you can regard this as a
thyristor with an anode gate as well as a cathode gate - and if you ignore
the cathode gate its a PUT.