Positive SSL
1 如圖所示,VCC = 9V、RB1 = 100kΩ、RB2 = 50kΩ、RC1 = 5kΩ、RE1 = 3kΩ、RE2 = 2kΩ、RC2 = 3kΩ,假設NPN、PNP電晶體之β值均為100,試求VC2電壓值為何?(90統測)
A 4
B 6.7
C 5.6
D 3.3

第一級輸入化成戴維寧等效電路:

等效電壓 = `9 * (100k) /(100k+50k)` = 3V

等效電阻 = 100k// 50k = 33kΩ

`33k * I_(B1) + 100 *I_(B1) * 3k` = `3 - 0.7`

`333k * I_(B1)` = 2.3

` I_(B1)` = `2.3/(333k)`

` I_(E1)` = `230/(333k)`

`V_(E1)` = `9-230/(333k)*5k` = 5.54V

` I_(E2)` = `(9-0.7-5.54)/(2k)` =1.38mA

` V_(C2)` 電壓 = ` R_(C2)` 兩端電壓

` V_(C2)` = 1.38m * 3k = 4.14V