W1 - Lab1 Frequency Response-OL (2)

4. Calculate β ac β ac = Δ Ic Δ Ib = ¿ 158.04nA 5. Measure the DC current at the emitter I E = 1.80mA 6. Calculate r’e r’e = 14.32Ω 7. Measure the AC voltage at the Load. Vout = 844mV 8. Measure the AC voltage at the Source. Vin = 20mv 9. Calculate the mid-band gain. A V = A M = V out V ¿ = 42.2 10. Convert the mid-band gain to its dB value A V(dB) = 20log ( 42.2 ) = 32.51 dB 11. Calculate the low frequency cutoff values due to the 3 external capacitances. Show your work and record the values in Table 1. a. Frequency due to the input capacitor. The source resistance in this case is in series with Rin(tot) f c 1 = 1 2 π ( R S + ( R 1 | | R 2 | | ( β ac ( r ' e + R E 1 ) ) ) ) C 1 Equation 1 1 2 π ( 600 + ( R 1 | | R 2 | | ( 158 ( 14.32 + 32 ) ) ) ) C 1 158 ∗ ( 14.32 + 32 ) = 7318.6 1 ( 1 68000 + 1 22000 + 1 7318 ) = 5081.048166 1 2 π ( 5081 ∗ 100 ∗ 10 − 9 ) = 313. 2354715 Hz b. Frequency due to the bypass capacitor. The source resistance in this case is in parallel. f c 2 = 1 2 π ¿¿ Equation 2 2 π ( R E 2 ∨ ¿ ( 14.32 + 32 + 5081 158 ) ) C 2