ommon Base onfguraton nput caracterstcs: s. B wt B const Output caracterstc: s. B wt const Pcture from ref [2] S. Lneykn, ntroducton to electroncs Slde [53] ommon Base Termnal caracterstcs [2] α BO FB 10 7 A α 0.99 ( ) BO Pcture from ref [2] S. Lneykn, ntroducton to electroncs Slde [54] BO KL : + B ( B + ) BO α + α β BO + B + B ( 1 α ) ( 1 α ) O 1
bers-moll model for acte regon (large sgnal) S. Lneykn, ntroducton to electroncs Slde [55] bers-moll model for acte regon (large sgnal) S. Lneykn, ntroducton to electroncs Slde [56] 2
Analytcal model bers-moll model of Transstor (acte regon) B S S BS B T ( e 1) B B T S T ( e 1) ( e 1) α B B T S T ( e 1) ( e 1) β S. Lneykn, ntroducton to electroncs Slde [57] nternal Feedback ffect and Output Resstance S. Lneykn, ntroducton to electroncs Slde [58] 3
H-parameters n B-mode Measurement metod 11 21 22 1 2 0 1 12 1 1 0 2 2 2 0 1 2 1 0 2 ; ; ; eb b rb fb ob e cb e 0 eb cb 0 c cb 0 e c e 0 cb defntons S. Lneykn, ntroducton to electroncs Slde [59] Small-sgnal parameters S. Lneykn, ntroducton to electroncs Slde [60] 4
ommon mtter Termnal caracterstc [2] Pcture from ref [2] S. Lneykn, ntroducton to electroncs Slde [61] Small sgnal e, oe S. Lneykn, ntroducton to electroncs Slde [62] 5
arly oltage arly effect: W ( ) > W ( ) 1 1 2 2 Depleton layer of B-Juncton ncreases wt > current ncreases Te densty of electrons n B-Juncton ncreases wt B > current ncreases 1 + B T Se A S. Lneykn, ntroducton to electroncs Slde [63] Small sgnal fe fe dc 0 100 ce d c Q b b S. Lneykn, ntroducton to electroncs Slde [64] 6
Small sgnal: g m e be 1 db de 1 1 1 e Q Q for 1mA, e 2.6kΩ ce ; α 0 d β d g b d e d α be α be for ( β + 1) r ( β + 1) e ma [ ] c e 1, 0.04 1/ Ω m m Q Q m dbe dbe re T e S. Lneykn, ntroducton to electroncs Slde [65] g T g β Small sgnal: re be re 1 c 0 ce m S. Lneykn, ntroducton to electroncs Slde [66] 7
Small sgnal: 1/ oe (r o ) Pcture from ref [3] 1 oe ce ro b 0 c dc oe Q, for 1mA, ro 100kΩ d + ce A S. Lneykn, ntroducton to electroncs Slde [67] Large and small sgnal model for acte regon Pcture from ref [3] S. Lneykn, ntroducton to electroncs Slde [68] 8
Small sgnal model (T) Pcture from ref [3] S. Lneykn, ntroducton to electroncs Slde [69] π-model Pcture from ref [3] S. Lneykn, ntroducton to electroncs Slde [70] 9
Small Sgnal Models of BJT S. Lneykn, ntroducton to electroncs Slde [71] Transstor: lementary crcuts ommon mtter () ommon Base (B) ommon ollector () S. Lneykn, ntroducton to electroncs Slde [72] 10
Pcture from ref [3] S. Lneykn, ntroducton to electroncs Slde [73] 1. amplfer Pcture from ref [3] S. Lneykn, ntroducton to electroncs Slde [74] 11
-example 10, 1mA, O 5 A 100, β100, S 10fA Fnd: Grapcal soluton, BB, B, R Small sgnal parameters Draw a small sgnal equalent crcut Sole te crcut S. Lneykn, ntroducton to electroncs Slde [75] grapcal soluton S. Lneykn, ntroducton to electroncs Slde [76] 12
Q-pont soluton,, BB, B, R R B BB 10uA β B + T O ln 5kΩ 1.01mA S 656m S. Lneykn, ntroducton to electroncs Slde [77] Small sgnal equalent crcut parameters o fe m re β 100 T re g e ( 1+ β ) α 1 0.04 r Ω e r A 0 26Ω + r e 2.6kΩ 105kΩ S. Lneykn, ntroducton to electroncs Slde [78] 13
Small Sgnal equalent crcut o A o A A p s s g ( r R ) ro r + R g A A 200 100 20k fe m o o R << ro R << ro fe m R 100 200 S. Lneykn, ntroducton to electroncs Slde [79] Small Sgnal equalent crcut R R R n o O r 2.6kΩ R R 5kΩ ( R ) r 100kΩ o e o S. Lneykn, ntroducton to electroncs Slde [80] 14
2. amplfer Pcture from ref [3] S. Lneykn, ntroducton to electroncs Slde [81] -example 10, 1mA, O 5 A 100, β100, S 10fA Fnd: Grapcal soluton, BB, B, R Small sgnal parameters Draw a small sgnal equalent crcut Sole te crcut S. Lneykn, ntroducton to electroncs Slde [82] 15
-grapcal soluton S. Lneykn, ntroducton to electroncs Slde [83] Q-pont soluton,, BB, B, R R B R 10uA 1.01mA BB 0 O α R O O + 4.95kΩ 5 T ln S 5.656 S. Lneykn, ntroducton to electroncs Slde [84] 16
Small sgnal equalent crcut parameters o fe m re β 100 T re g e ( 1+ β ) α 1 0.04 r Ω e r A 0 26Ω + r e 2.6kΩ 105kΩ S. Lneykn, ntroducton to electroncs Slde [85] Small Sgnal equalent crcut Pcture from ref [3] S. Lneykn, ntroducton to electroncs Slde [86] 17
R n Pcture from ref [3] S. Lneykn, ntroducton to electroncs Slde [87] R O Pcture from ref [3] S. Lneykn, ntroducton to electroncs Slde [88] 18
3. B amplfer Pcture from ref [3] S. Lneykn, ntroducton to electroncs Slde [89] B-example 10, 1mA, O 5 A 100, β100, S 10fA Fnd: Grapcal soluton, BB, B, R Small sgnal parameters Draw a small sgnal equalent crcut Sole te crcut S. Lneykn, ntroducton to electroncs Slde [90] 19
B grapcal soluton S. Lneykn, ntroducton to electroncs Slde [91] Q-pont soluton,, BB, B, R R B BB B T + O 10uA β ln + 1.01mA S O 5kΩ 656m S. Lneykn, ntroducton to electroncs Slde [92] 20
Small sgnal equalent crcut parameters o fe m re β 100 T re g e ( 1+ β ) α 1 0.04 r Ω e r A 0 26Ω + r e 2.6kΩ 105kΩ S. Lneykn, ntroducton to electroncs Slde [93] Small Sgnal qualent rcut S. Lneykn, ntroducton to electroncs Slde [94] 21
B: A S. Lneykn, ntroducton to electroncs Slde [95] B: Rn, Ro S. Lneykn, ntroducton to electroncs Slde [96] 22