A tetrode transistor is any
transistor
upright=1.4, gate (G), body (B), source (S) and drain (D) terminals. The gate is separated from the body by an insulating layer (pink).
A transistor is a semiconductor device used to Electronic amplifier, amplify or electronic switch, switch ...
having four active terminals.
Early tetrode transistors
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.
*Point-contact transistor having two emitters. It became obsolete in the middle 1950s.
*Modified grown-junction transistor or alloy-junction transistor having two connections at opposite ends of the base. It achieved its high speed by reducing the input to output
capacitance
Capacitance is the capability of a material object or device to store electric charge. It is measured by the change in charge in response to a difference in electric potential, expressed as the ratio of those quantities. Commonly recognized a ...
. It became obsolete in the early 1960s with the development of the
diffusion transistor
A diffused junction transistor is a transistor formed by diffusing dopants into a semiconductor substrate. The diffusion process was developed later than the alloy junction and grown junction processes for making bipolar junction transistors (B ...
.
Modern tetrode transistors
*Dual emitter transistor, used in two-input
transistor-transistor logic gates
*Dual collector transistor, used in two-output
integrated injection logic gates
*
Diffused planar silicon bipolar junction transistor,
[ - ''Tetrode transistor memory logic cell'', March 6, 1979. Filed September 6, 1977.] used in some
integrated circuits. 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 tetrode
See also
*
Multigate transistor
A multigate device, multi-gate MOSFET or multi-gate field-effect transistor (MuGFET) refers to a metal–oxide–semiconductor field-effect transistor (MOSFET) that has more than one gate on a single transistor. The multiple gates may be control ...
.
*
Pentode transistor A pentode transistor is any transistor having five active terminals.
Early pentode transistors
One early pentode transistor was developed in the early 1950s as an improvement over the point-contact transistor.
*A point-contact transistor having thr ...
References
External links
Some application aspects of the tetrode transistorsPDF (point contact)
The Tetrode Power TransistorPDF (alloy junction)
(grown junction)
Transistor types
{{Electronic components