Tetrode transistor: Difference between revisions

{{Short description|Transistor with four active terminals}}A '''tetrode transistor''' is any [[transistor]] having four active terminals.

There were two types of tetrode transistor developed in the early [[1950s]] as an improvement over the [[point-contact transistor]] and the later [[grown -junction transistor]] and [[alloy -junction transistor]]. Both offered much higher speed than earlier transistors.

*Modified grown -junction transistor or alloy -junction transistor having two connections at opposite ends of the base.<ref>{{cite book

| first = Oswald |author2=R. T. Kramer |author3=J. Spiech |author4=H. Shleuder

| dateyear = 1966

| pages = pp. 98-&ndash;102}}</ref>. It achieved its high speed by reducing the input to output [[capacitance]]. It bacamebecame obsolete in the early 1960s with the development of the [[diffusion transistor]].

*Dual emitter transistor, used in two -input [[transistor-transistor logic]] gates.

*Dual collector transistor, used in two -output [[integrated injection logic]] gates.

*[[Planar transistor|Diffused planar silicon bipolar junction transistor]],<ref>{{US patent|4143421}} - ''Tetrode transistor memory logic cell'', March 6, 1979. Filed September 6, 1977.</ref>, used in some [[integrated circuit]]s. This transistor, apart from the three electrodes, (emitter, base, and collector), has a fourth electrode or grid made of conducting material placed near the emitter-base junction from which it is insulated by a silica layer.

*[[Field -effect transistortetrode]]s having two gates.