Tutorial: Mechanic - electrician Topic: Technical training II. class Transistors 2 Prepared by: Melichařík Lubomír Projekt Anglicky v odborných předmětech, CZ.1.07/1.3.09/ je spolufinancován Evropským sociálním fondem a státním rozpočtem České republiky.

 UNIPOLAR TRANSISTORS  -transistors driven by the electric field  -has (at least) three electrodes, which are referred to as drain, gate, source  -unipolar transistors are referred to as N-FET or P-FET.

 Electrotechnical schematic symbol of a JFET transistor

 Electrotechnical schematic symbol of a transistor MOSFET induced

 Electrotechnical schematic symbol of a transistor MOSFET embedded

 TYPES OF UNIPOLAR TRANSISTOR JFET- (Junction FET) control electrode(gate) is formed by reverse polarized transition PN.  - transistor works in a so-called depleted mode - at zero voltage it is fully open  - in the reverse polarized transition the conductive channel narrows  MOSFET- (Metal Oxide Semiconductor FET) control electrode(gate) is isolated from the rest of the transistor oxide. It can work in the depleted and enriched mode.  - in the transistor MOSFET with an induced channel N there is a conducting channel only after applying the positive U, thus it only works in the enriched mode.  - for transistors with a channel with a semiconductor- type P there are opposite voltages

 TYPES OF UNIPOLAR TRANSISTORS -MESFET- (Metal Semiconductor FET) control electrode (gate) is formed by reverse polarized transition metal- metalloid. -MISFET- (Metal Insulated Semiconductor FET) Common name for a transistor with an insulated control electrode. Insulator need not be just carbon (eg... nitride).

 1. What is a unipolar transistor?  2. How many electrodes has a unipolar transistor?  3. What are the names of the electrodes?  4. Describe the basic types of unipolar transistors

 1. Draw the schematic symbol for a JFET transistor.  2. Draw the schematic symbol of a transistor MOSFET induced.  3. Draw the schematic symbol of a transistor MOSFET embedded.

 Václav MalinaPoznáváme elektroniku I.  Adrian Schommers Elektronika tajemství zbavená. ISBN