elektronika lanjut.e2f

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  1. Pada gambar (a) gambarlah garis beban ac dan hitunglah kepatuhan kluaran ac-nya

gambar a

Penyelesaian :

IE =(10v- 0,7v)/200Ω

= 46,5 . 10­-3 ampere

vE = IE . RE = 70,6.10-3 ampere

= 46,5. 10-3.200

= 9,3 volt

vc = 10- (46,5.10-3.100)

= 5,35 volt

Ic = ICQ = 5,35/200

= 26,75 .10-3


VCEQ = VC - VE

= 5,35 – 9,35

= 3,95 volt

RC = RC // RL

= 100//900

= 90

II (sat) =IC Q + VCEQ / VC

= 26,75 .10-3 + 3,95/90

= 70,6.10-3 ampere

VCE(cut) = VCEQ + ICQrC

= 3,95 + 26,75.10-3.90

= 6,35 volt

I = VCC/RC+RE

=10/100+200

= 33,3 mA

Kepatuhan

PP = 2(Tcq. Ic)

= 2 (2,40)

= 4,80 Volt

2. kepatuhan keluaran ac tahap 1? garis beban ac untuk tahap 2?

Gambar b

Tahap 1

IE = (2,14 – 0,7)/ 1kΩ

= 1,44.10-3 Ampere

VE = 2,5 k / (15 k + 2,5 k) x 15

= 2,14 volt

Vc = 10 V – (1,44.10-3. 3,3 k)

= 5,248 Volt

IC = ICQ

= (5,428 v) / (3,3 k)

= 1,59.10-3Ampere

Kepatuhan tahap I

PP = 2 (TCQ rC ) VTH

= 2 (1,59 x 10-3 x 2,5 k)

=7,95 Volt

IJenuh = IC Q +VCEQ / VC

= 1 x 10-3 + (8,2 k/4,1 k)

VCE = 8,2 + (1x10-3x4,1)

= 12,3 Volt


Tahap 2

I1 = VCC / (20 K+ 20 K)

= 0,375 x 10-3 ampere

I2 = ICQ = IE = 1 x 10-3

IC = ICQ = IE = 1 x 10-3

IS = 1,375 x 10-3 A

RS = 15/(1,375 x 10-3 A)

= 10,909 KΩ

rE = RE //RL

= 8,2 k//8,5 k

= 4,1 K

VTH = (20k/40k)x 15

= 7,5 Volt

= 7,5 V – 0,7 V

= 6,8 v

VCEQ = VC - VE

= 15 – 6,8 = 8,2 V



3. penguras arus dc total (pada gambar b)


tahap 1

ICQ = 26,75 x 10-3 ampere

R1 = 2,5 kΩ

R = 15 kΩ

Vcc = 15 volt

I1 = 15 / 2,5 kΩ + 15 kΩ

I1 = 0, 85 x 10-3 ampere

I2 = ICQ = 26,75 x 10-3 ampere

Is1 = 27,6 x 10-3 ampere

Sehingga :

Is total =Is1 + Is2

= 27,6 x 10-3 + 1,375 x 10-3

= 28,975 x 10-3


tahap 1

ICQ = 1 x 10-3

R1 = 20 kΩ

R2 = 20 kΩ

Vcc = 15 volt

I1 = 15/ 20 kΩ + 20 kΩ

= 0,375 x 10-3 ampere

I2 = ICQ = 1 x 10-3 ampere

I Is2 = 1,375 x 10-3 ampere



4. efisiensi tahap II

diketahui tahap II

ICQ = 1 x 10-3 ampere

rE = 4,1

PP 2 ( 4,1 kΩ . 1 x 10-3)

8,2 volt

η = (PL max) / (Ps max) x 100 %

= (PP2 / 8 RL) / (Ps )x 100 %

=[ (8,2)2 / 8(8,5 )] / (15 x 1,375 x 10-3) x 100%

= 9,8 x10-4 / 20,625 x 10-3 x 100 %

= 4,75 %