전자공학철도신호기사 · 2016년10월01일 · 7/80
7.다음 회로의 안정계수를 구하면? (단, +VCC=10V, R1=3kΩ, R2=2kΩ, β=100, Re=3kΩ, Rc=3kΩ이다.)
1
10
2
1.4정답
3
2.45
4
101
해설
Voltage Divider Bias - This is the most widely used method to provide biasing and stabilization to a transistor. - In this form of biasing, R1 and R2 divide the supply voltage Vcc and voltage across R2 provide fixed bias voltage VB at the transistor base. - Also a resistance Re is included in series with the emitter that provides the stabilization. S = (β+1) x (1 + Rth/Re) / {(β+1) + Rth/Re} ∴Rth = R1//R2 = 3x2 / (3+2) = 1.2[kΩ] = 101 x (1 + 1.2/3) / (101 + 0.4) = 141.4 / 101.4 = 1.394477318