Due Friday 2019-01-25 at the start of class.

1. Reading

Emitter Read [AoE] from section 2.2.3 through the end of section 2.2.6 (page 87).

Read [AoE] section 2.3.7, paying attenting to Figure 2.60. The “(figure out why)” at the end of page 101 is the goal of the Lab 1-B Current Mirror circuit.

Supplemental: read [L-AoE] chapter 4N.

2. Complete the lab circuits

For each of the Lab 1 versions. It is completely valid to build them also to check your hand work!

Lab 1-A Emitter Follower:

  • Find the values of the checkboxed items.

  • Additional: Sweep source Vs and find the operating modes of Q1 over this range. Write down as a table of Vs ranges and the corresponding Q1 mode.

Lab 1-B Current Mirror:

  • Find the values of the checkboxed items.

  • Additional: Sweep source Vs and find the operating modes of Q2 over this range. Write down as a table of Vs ranges and the corresponding Q2 mode. (Q1 is always either in cutoff or at the boundary between active and saturation — "diode-connected")

3. AoE - Exercise 2.8 (p. 84)

Design an emitter follower with ±15 V supplies to operate over the audio range (20 Hz to 20 kHz). Use 5 mA quiescent current and capacitive input coupling.

This problem uses results from Lab 1-A Emitter Follower: §2.2 Amplifier. The solution looks suspiciously like AoE Figure 2.25 or 2.27 (there are other reasons for choosing between these two topologies). You want the input series capacitor to have an impedance _much lower that the input impedance of the amplifier (\(R_1 || R_2\) or \(R_B\)) over the specified frequency range. “Much lower than” can be \(|Z_C| < \frac{1}{10} R_{in}\) for this exercise.

Additional hw question

  • What is the maximum load (minimum Rload value) that can be used with this amplifier and still maintain an output signal swing of at least 16 V peak-to-peak?

4. Current mirror compliance

What is the output compliance of the current mirror measured in Lab 1-B Current Mirror: §2.1 Current mirror operation?

The term compliance is defined in [AoE] §2.2.6.D (p. 86).

References