Part 4 Bipolar Junction Transistors BJTs .


38 views
Uploaded on:
Description
Chapter 4 – Bipolar Junction Transistors (BJTs). Introduction. http://engr.calvin.edu/PRibeiro_WEBPAGE/courses/engr311/311_frames.html. Physical Structure and Modes of Operation. A simplified structure of the npn transistor. Physical Structure and Modes of Operation.
Transcripts
Slide 1

Part 4 – Bipolar Junction Transistors (BJTs) Introduction http://engr.calvin.edu/PRibeiro_WEBPAGE/courses/engr311/311_frames.html

Slide 2

Physical Structure and Modes of Operation A disentangled structure of the npn transistor.

Slide 3

Physical Structure and Modes of Operation A streamlined structure of the pnp transistor.

Slide 4

Operation of The npn Transistor Active Mode Current stream in a npn transistor one-sided to work in the dynamic mode, (Reverse current parts because of float of thermally created minority transporters are not appeared.)

Slide 5

Operation of The npn Transistor Active Mode Profiles of minority-bearer focuses in the base and in the emitter of a npn transistor working in the dynamic mode; v BE  0 and v CB  0.

Slide 6

Operation of The npn Transistor Active Mode Current Flow The Collector Current The Base Current The Emitter Current

Slide 7

Equivalent Circuit Models Large-flag comparable circuit models of the npn BJT working in the dynamic mode.

Slide 8

The Constant n The Collector-Base Reverse Current The Structure of Actual Transistors

Slide 9

The pnp Transistor Current stream in a pnp transistor one-sided to work in the dynamic mode.

Slide 10

The pnp Transistor Two extensive flag models for the pnp transistor working in the dynamic mode.

Slide 11

Circuit Symbols and Conventions

Slide 12

Summary of the BJT Current-Voltage Relationships In Active Mode

Slide 13

Example 4.1

Slide 14

Exercise 4.8 and 4.9

Slide 15

The Graphical Representation of the Transistor Characteristics

Slide 16

Dependence of ic on the Collector Voltage – Early Effect The i C - v CB attributes for a npn transistor in the dynamic mode.

Slide 17

Fig. 4.15 (a) Conceptual circuit for measuring the i C - v CE qualities of the BJT. (b) The i C - v CE attributes of a commonsense BJT.

Slide 18

Fig. 4.23 (a) Conceptual circuit to show the operation of the transistor of an enhancer. (b) The circuit of (a) with the flag source v be disposed of for dc (inclination) examination.

Slide 19

Fig. 4.24 Linear operation of the transistor under the little flag condition: A little flag v be with a triangular waveform is superimpose clamor the dc voltage V BE . It offers ascend to an authority flag current i c , likewise of triangular waveform, superimposed on the dc current I C . I c = g m v be , where g m is the slant of the i c - v BE bend at the predisposition point Q.

Slide 20

Fig. 4.26 Two somewhat extraordinary forms of the disentangled crossover  show for the little flag operation of the BJT. The identical circuit in (a) speaks to the BJT as a voltage-controlled current source ( a transconductance speaker) and that in (b) speaks to the BJT as a current-controlled current source (a present enhancer).

Slide 21

Fig. 4.27 Two somewhat unique forms of what is known as the T model of the BJT. The circuit in (a) will be a voltage-controlled current source representation and that in (b) is a current-controlled current source representation. These models unequivocally demonstrate the emitter resistance r e instead of the base resistance r  included in the half breed  show.

Slide 22

Fig. 4.29 Signal waveforms in the circuit of Fig. 4.28 .

Slide 23

Fig. 4.30 Example 4.11: (a) circuit; (b) dc investigation; (c) little flag show; (d) little flag examination performed straightforwardly on the circuit.

Slide 24

Fig. 4.34 Circuit whose operation is to be dissected graphically.

Slide 25

Fig. 4.35 Graphical development for the assurance of the dc base current in the circuit of Fig. 4.34 .

Slide 26

Fig. 4.36 Graphical development for deciding the dc gatherer current I C and the authority to-emmiter voltage V CE in the circuit of Fig. 4.34.

Slide 27

Fig. 4.37 Graphical assurance of the flag parts v be , i b , i c , and v ce when a flag segment v i is superimposed on the dc voltage V BB (see Fig. 4.34 ).

Slide 28

Fig. 4.38 Effect of inclination point area on passable flag swing: Load-line An outcomes in predisposition point Q A with a relating V CE which is excessively near V CC and along these lines constrains the positive swing of v CE . At the other outrageous, stack line B brings about a working point excessively near the immersion area, hence constraining the negative swing of v CE .

Slide 29

Fig. 4.44 The normal emitter intensifier with a resistance R e in the emitter. (a) Circuit. (b) Equivalent circuit with the BJT supplanted with its T show (c) The circuit in (b) with r o killed.

Slide 30

Fig. 4.45 The regular base speaker. (a) Circuit. (b) Equivalent circuit acquired by supplanting the BJT with its T display.

Slide 31

Fig. 4.46 The normal gatherer or emitter-devotee enhancer. (a) Circuit. (b) Equivalent circuit acquired by supplanting the BJT with its T display. (c) The circuit in (b) redrawn to demonstrate that r o is in parallel with R L. (d) Circuit for deciding R o.

Slide 32

Fig. 4.55 A npn resistor and its Ebers-Moll (EM) show. The scale or immersion streams of diodes D E (EBJ) and D C (CBJ) are demonstrated in brackets.

Slide 33

Fig. 4.59 The vehicle model of the npn BJT. This model is precisely proportionate to the Ebers-Moll model of Fig. 4.55 . Take note of that the immersion streams of the diodes are given in brackets and i T is characterized by Eq. (4.117).

Slide 34

Fig. 4.60 Basic BJT advanced rationale inverter.

Slide 35

Fig. 4.61 Sketch of the voltage exchange normal for the inverter circuit of Fig. 4.60 for the case R B = 10 k  , R C = 1 k  ,  = 50, and V CC = 5V. For the count of the directions of X and Y allude to the content.

Slide 36

Fig. 4.62 (a) The minority-transporter fixation in the base of an immersed transistor is spoken to by line (c). (b) The minority-transporter charge put away in the base can de separated into two parts: That in blue delivers the slope that offers ascend to the dissemination current over the base, and that in dim outcomes in driving the transistor more profound into immersion.

Slide 37

Fig. 4.63 The i c - v cb or normal base attributes of a npn transistor. Take note of that in the dynamic district there is a slight reliance of i C on the estimation of v CB . The outcome is a limited yield resistance that reductions as the present level in the gadget is expanded.

Slide 38

Fig. 4.64 The half and half  show, including the resistance r  , which models the impact of v c on i b .

Slide 39

Fig. 4.65 Common-emitter qualities. Take note of that the even scale is extended around the starting point to demonstrate the immersion locale in some detail.

Slide 40

Fig. 4.66 An extended perspective of the regular emitter attributes in the immersion district.

Recommended
View more...