Lecture K No lectures on Thursdays anymore! Yeah! Mid-term in ~3 weeks. Covers all materials we covered up that date (lectures and labs) Start thinking about your final projects! (Proposal due in 5 weeks) Our Trusty LF356 contains about a dozen transistors (BJTs and FETs) Modern CPUs and GPUs contain well over 1 billion transistors. Some memory chips even several 10 billions (mostly FETs)! (Sorry. No circuit diagram for this one) Moores Law Curve shows Moores Law: Transistor count doubling every two years Analogy of current in n and p-doped semiconductors Energy Momentum n-doped p-doped un-doped (intrinsic) Electrons carry the current. Holes carry the current. Traffic jam! Current cannot flow. Based on the V CE vs. I C plot on the board, what is the current gain h fe ? L1 A)1 B)10 C)100 D)200 E)1000 What is V out for an emitter follower? L2 A)I B R E B)V in C)10 V V D)V in V E)V in 0.6 V What is V E for a emitter follower? L3 I B R E I E R E C)0 V D)+ 0.6 V E) 0.6 V What is the input impedance for an emitter follower? L4 R e C)R e D)1/ ( +1) E)R e /( +1) What is V out for a common emitter amplifier? L5 A)V cc - h fe R C I B B)V in - h fe R C I B C)V cc - R C I B D)V in - R C I B E)I donno. What is the quiescent base voltage, V B ? L6 A)15 V B)5V C)3 V D)2.5 V E)0 V What is the quiescent emitter voltage, V E ? L7 A)15 V B)14.6V C)3.1 V D)2.5 V E)1.9 V What is the collector current, I C ? L8 A)15 mA B)3 mA C)2.5 mA D)1.9 mA E)0.6 mA What is the collector voltage, V C ? L9 A)15 V B)5.5 V C)3.1 V D)2.5 V E)0 V How much power is dissipated in the transistor? L10 A)22.7 mW B)18.1 mW C)10.4 V D)6.8 mW E)No power is dissipated What is the AC voltage gain? L11 A)-6 B)-5 C)-50 D)-60 E)-1 21 For the (properly biased) input voltage signal shown below, which of the following choices best represents the output voltage signal for the circuit at right? 22 V in is a 1 kHz signal with peak-to-peak amplitude of 1 V. A) A > B > C B) B > A > C C) B > C > A D) B > A = C E) C > A > B Rank the three circuits according to the peak-to-peak amplitude of V out. 23 For V in as shown, rank outputs 1, 2, and 3 according to peak-to- peak amplitude from largest to smallest A)1 > 2 > 3 B)1 > 2 = 3 C)2 = 3 > 1 D)2 > 3 > 1 E)3 > 2 = 1 24 Suppose a 1-k resistor is added to the circuit as shown at right. A)Increase B)Decrease C)Remain the same D)Not enough information When the resistor is added, the peak-to- peak amplitude of output 1 (for the same input signal) will: 25 V in is a 1 kHz signal with peak-to-peak amplitude of 1 V. A)A > B > C B)B > A > C C)B > C > A D)B > A = C E)C > A > B Rank the three circuits according to the peak-to-peak amplitude of V out.