Question

All lower and upper of the booster circuit with FET in the figure find the cutoff frequencies. As a result of all the circuit.Determine the valid lower and upper cutting frequency for. Note: The output resistance of the FET is large enough to be neglected 20 V Cw Cw. 4 pF Cgd = 8 pF = 6 pF Cgs = 12 pF Cds = 3pF 3.9 ks2 220 k12 W 6.8 uF It V 1.5 k12 V wta TuF I loss = 10 mA Vp = -6 V 5.6 ks2 Vs 2 68 k 2 2.2 k2 10uF

Answer 1

tds from Low-frequency Response of FET amplifier lower cut off frequency fia 20 (Rsig. + R;) Cu between Capacitor Where CG = Co= coupling active device the source input Resistance Rio i.e. 11 R2 R; R] AC equivalent model of given frog 1.5kg IMF mH Rsig + Cer become slm and For coupling capacitor between the caftine iie. Ce: 6.8 uf device & the load network The cut off frequency - fur Lc an (Roth, Ce Ro Ro where, Ro= Olp resistance Lonel resistance the RI for source capacitor ç, the resistance and level of importance is defined The cut off frequeney ㅗ fust 27 Reg. Cs where Req = Equivalent resistence ra os I Req Rs ll In Data Given! from the circuit given 11 12 1.sks Rsig 220k12 11 220 X 68 ka 220 +68 K2 k = 3.9kr si bur - gna gno Req. RS" a loss gro = 2 (10A) 23.33ms GU Las gon one C's Ve VGS VGTERS = 3.33ms ( old Va 68602 (201) 68k2 +220kh = 3.33ms -2.SIV 6V varsa 5-2.55V - 4.72 v Vas = 4.72 lo (2.262) loss (1-4651V.) Isa - 3.3 na Ignal.aims Yote: Instead of solving equation approch hit & trial method to oftein Iso e VGsQ 1.sk // ㅗ 1.9ins =) Reg." 1.sk2 ll 0.523 kr 0.388 kr Ca. = IMF, (= 6.8MF, Cs=10 MF Solution fia 2T (1.542 +51,944 2) llur fuga 2.98 HZ (Ams. fuc 27 (3.8kn 45.6K2) (6.9 uf) fic H2 2.46 Ans. fis 2x (0.388K2) (10u) 4 1 HZ fis response of FET Amplifier from high frequency 1 2aRth C; fwand 11 р. Atha IR, Rsig. 1.5 kr Il 57.94 kr - 1.46 kr (; - Cw; + Ggs +(1-Av Cgy = 4pf + 12 pr t Ci-A,) 8 of Note: values AU the .. Aus care given in circuit diagram. -gn (Rp 11h) =-1.91ms (3.96.211 ST6K2) -4.39 >> C;: 16 pf + C1-(-4.34) 8.p.f 59.12 pf - IN fity 27 (1.46 ks) (59,12 p-f) fH; 1.84 MHZ {er.] ㅗ the Pthe Ro "IRL 20rtha Co 3.9k2 l 5.6 kus 2.3k2 coa f ..) Cad - Got + 3,8 + Co-entry) of 18.82 pf of Ho 20 (2.3K2) (18.82 pf) [Ans.] f Hoa 3.68 mit z