1. 2016-02-04Mobile Communication Lab. (http://mobile pknu.ac.kr)1 Chapter 8. Transistor bias

2. 2016-02-04Mobile Communication Lab. (http://mobile pknu.ac.kr)2  8-1. VDB (Voltage-Divider Bias) (β dc 에 무관 )

3. 2016-02-04Mobile Communication Lab. (http://mobile pknu.ac.kr)3  8-2. Accurate VDB Analysis V TH R TH 부하선 보통 R 2 <R 1 이므로 R TH R 2

4. 2016-02-04Mobile Communication Lab. (http://mobile pknu.ac.kr)4  8-3. VDB Load Line and Q point ① ② ③ (for R E = 1k) (for R E = 2.2k) (for R E = 510Ω) * Q Variation points : V CC, R 1, R 2, R C * But R E → Simple Variations of Q point

5. 2016-02-04Mobile Communication Lab. (http://mobile pknu.ac.kr)5  8-4. Two-supply Emitter Bias V BE + - ① ②

6. 2016-02-04Mobile Communication Lab. (http://mobile pknu.ac.kr)6 ex ) * Simplify

7. 2016-02-04Mobile Communication Lab. (http://mobile pknu.ac.kr)7  8-5. Other Types Biasing ① Base Bias Switching

8. 2016-02-04Mobile Communication Lab. (http://mobile pknu.ac.kr)8 ② Emitter-feedback Bias β dc ( 大 ) → I C ( 大 ) → V RE ( 大 ) (a) (b) β dc 영향 → V RB ( 小 ) → I B ( 小 ) → IC ( 小 ) → βdc ( 감소 ) ( 고찰 ) if ) → β dc 영향 무시가능 * β dc 의 3 : 1 변화는 I C 를 거의 3 : 1 로 변화시킴 RBRB RCRC RERE V CC

9. 2016-02-04Mobile Communication Lab. (http://mobile pknu.ac.kr)9 ex 8.6 )  ( V RL )   ( V RE )    

10. 2016-02-04Mobile Communication Lab. (http://mobile pknu.ac.kr)10 ( V R2 ) ( V RE ) (Base - GND) (Emitter - GND)

11. 2016-02-04Mobile Communication Lab. (http://mobile pknu.ac.kr)11 ③ Collector-feedback Bias (or self-bias) I B + I C ICIC * β dc 3 : 1 → I C 2 : 1 less β dc ( 大 ) → I C ( 大 ) → V RC ( 大 ) → V RB ( 小 ) → I B ( 小 ) → I C 감소 * 포화전류 : 차단전압 : IBIB

12. 2016-02-04Mobile Communication Lab. (http://mobile pknu.ac.kr)12 * β dc 영향 0 → 포화점에 달할 수 없다 로 하면부하선의 중앙점 + - - + 0.7 > 0.7 ( 포화점에 달할 수 없다 )

13. 2016-02-04Mobile Communication Lab. (http://mobile pknu.ac.kr)13 ④ Collector-AND Emitter-feedback Bias

14. 2016-02-04Mobile Communication Lab. (http://mobile pknu.ac.kr)14  8-7. PNP Tr + - V CE + + - - V BE V CB ① npn Tr → pnp Tr 로 교체 ② 전류, 전압을 모두 역으로 -V CC +V EE + - V2V2 VBVB I VE’VE’ VCVC IEIE + - V E (V RE ) 동일