07 Chapter Map - Multivibrators, Memory & Converters

Chapter 7 Overview & Map of Content (MOC)

Multivibrator topologies (BJT and 555 timer), semiconductor and magnetic memory, Digital-to-Analog Converters (weighted-resistor and R-2R ladder), and Analog-to-Digital Converters (Flash, dual-slope, successive approximation).


📚 Study Notes Index

#NoteWhat it coversPYQ yearsTypical marks
7.017.01 Multivibrator Topologies (Astable, Monostable, Bistable & 555 Timer)Astable, monostable, bistable, 555 timernone—
7.027.02 Semiconductor & Magnetic Memory SystemsMagnetic core memory, EPROM/E²PROM, RAM/ROM classification2015–2025 (every paper)5–12
7.037.03 Digital-to-Analog Converters (DAC Topologies & Analysis)Weighted-resistor vs R-2R comparison, R-2R proof, resolution/accuracy/settling time2017–20256–10
7.047.04 Analog-to-Digital Converters (ADC Topologies & Applications)Dual-slope proof, SAR balance-and-weights, Flash2015–2025 (every paper)8–15
7.057.05 Chapter 7 Master PYQ Solutions & Converter PuzzlesAdditional worked converter problems——

🎯 Exam Weight

The densest concentration of repeat questions in the entire course

Four questions account for essentially every mark this chapter has ever been worth:

RankQuestionAppearancesMarksNote
1Dual-slope A/D proof108–137.04 Analog-to-Digital Converters (ADC Topologies & Applications) §3.2
1Short notes on EPROM and E²PROM105–107.02 Semiconductor & Magnetic Memory Systems §3
3Magnetic core memory — read/write process88–127.02 Semiconductor & Magnetic Memory Systems §2
4Weighted-resistor vs R-2R ladder DAC77–107.03 Digital-to-Analog Converters (DAC Topologies & Analysis) §4

That is 30–40 marks per paper from four questions, and three of the four are purely descriptive — no derivations, no circuit analysis. The dual-slope proof is four lines of integration.

If revision time is short, this chapter is the highest return per hour in ECE 2103.

Rising items in recent papers

  • R-2R proof — new in 2024, repeated 2025
  • Define resolution / accuracy / settling time — 2024 and 2025
  • SAR balance-and-weights design — 2021, 2023, 2025
  • Magnetic core “read and write” — the question expanded from write-only (2015–2020) to both (2021 onward)

The pattern suggests Chapter 7 is being examined more heavily over time, not less.

Syllabus topics with no exam history

Multivibrators — astable, monostable, bistable and the 555 timer — have never appeared in any paper from 2015 to 2025, despite occupying Week 8 of the teaching plan and an entire note (7.01 Multivibrator Topologies (Astable, Monostable, Bistable & 555 Timer)).

Also unexamined: Flash ADC, quantization-error numericals, RAM vs ROM and SRAM vs DRAM comparisons.

Read them once for coverage — a topic with no history is not the same as a topic that cannot appear — but do not let them compete with the four questions above.