Perfecting Analog Design : Analog design interview preparation:Introduction and content

Introduction

This blog is, as the name suggests, intended to be a guide for interview preparation for designers/ aspirants looking to review/ brush up their analog design basics.

The following are the headers that will be discussed in detail:

1. What to read (Content)
2. Where to read from ( Resources )
3. Practice problems
4. Miscellaneous items that are miscellaneous due to the above arbitrary choice of classification.

1. Content ( What to read)

The following topics must be covered thoroughly

Points 1 to 18 and Miller in point 19 are fundamentals. 

Points 5,12,13,16 are better understood using graphs.

1. Circuit laws: Ohms law, KCL, KVL
2. Circuit theorems: Thevenin;s theorem, Norton's theorem, Maximum power transfer theorem, Superposition, Reciprocity, Source transformation.
3. System properties: Causality, time in-variance, BIBO stability, linearity
4. The tools of Fourier and Laplace transform of common signals, Bode plots, 
5. First order RC circuits: Should be able to write/graph time domain and frequency domain response to input impulse, input step, input sinusoid without calculation/ pen paper analysis.
6. Should be able to tell approximate pole locations at each of the nodes of any order RC network. 
7. Step response of second order series and parallel RLC circuits.
8. Basic charge pump architecture related questions.
9. Concept of negative feedback, concept of stability, stability criterion, gain and phase margin and their limitations, open and closed loop transfer functions, properties of feedback ( impedance modification, bandwidth modification, gain desensitization) 
10. Ideal opamp as a building block, inverting and non-inverting configurations.
11. controlled sources: CCCS, CCVS, VCCS, VCVS, terminal impedances, achieving these using negative feedback.
12. Concept of biasing, linearizing and small-signal analysis.
13. Point 12 applied to diodes and MOSFETS. 
14. Basic circuit topologies: common source, common gate, common drain, cascode e.t.c.
15. Characterization ( i.e. how are they measured?) of mismatch and noise, understand why they are of concern to designers, how they are calculated in different circuit elements (MOSFETS, resistors etc) and circuit/ design techniques to minimize them.
16. Important second order effects: Channel length modulation, body effect, sub-threshold conduction.
17. Realizing controlled sources using MOSFETS.
18. Realizing opamps using MOSFETS. Different architectures: single stage differential to single ended- normal, telescopic cascode, folded cascode, two and more stage amplifiers.
19. Instability and compensation in two and more stage opamps: Miller, Ahuja, Feed-forward
20. Fully differential amplifiers.