STLD Notes and Study Material PDF Free Download

STLD Notes: Aspirants looking to get hold of the STLD Study Material and Notes can access the best notes for their preparation process or to have a revision of essential concepts.

The STLD Lecture Notes and Study Materials acts as the principal study material and notes that foster and enhance better preparation and helps students score better grades. Students can refer to the STLD Notes as per the latest curriculum from this article.

STLD Notes give aspirants a head start as they will also acquire the latest Syllabus, Reference Books, and Important Questions List for STLD notes over regular notes. STLD Notes and Study Material PDF Free Download.

Participants can benefit from the STLD Notes PDFs and Reference Books from this article and ace the preparation methods with the best and updated study resources and achieve better grades.

Introduction to STLD Notes

Switching Theory permits us to comprehend the activity and connection between Boolean Algebra and two-level rationale capacities concerning Digital Logic Gates. The exchanging hypothesis can be utilized to additionally build up the hypothetical information and ideas of computerized circuits when seen as an interconnection of info components creating a yield state or condition.

Computerized rationale entryways whose data sources and yield can switch between two particular consistent estimations of 0 and 1, can be characterized numerically just by utilizing Boolean Algebra. Be that as it may, we can likewise speak to the two advanced rationale conditions of HIGH or LOW, “1” or “0”, “ON” or “OFF”, and TRUE or FALSE, utilizing electromechanical contacts as switches or transfers as a rationale circuit component. The execution of exchanging capacities in computerized rationale circuits is the same old thing, however, it can give us a superior comprehension of how a solitary advanced rationale door functions.

STLD Notes and Study Material PDF Free Download

Aspirants pursuing their Bachelors in Technology (B.Tech) or anybody who is interested in learning about the software can avail from the STLD Notes and Study Material updated in this article. Students can aid your preparation with the ultimate preparation tools that help you score more marks.

Candidates can download the study material and notes and refer to them whenever during the preparation process. Use of the STLD Notes and Study Materials as a reference will help candidates get a better understanding of the concepts and change their score chart.

Here, is a list of a few important notes for a thorough preparation of the STLD  course programme-

  • STLD Notes PDF
  • STLD Handwritten Notes PDFs
  • STLD Notes for CSE PDFs
  • STLD Question Paper PDFs
  • STLD PPT Notes PDF

STLD Reference Books

Books are a rich source of information and students should refer books that provide excellent conceptual background. Candidates can avail the best books for STLD as recommended by the experts of the subject.

Pupils can refer and read through the STLD Books and other Study Sources during your preparation.

The list of best and highly recommended books for  STLD preparation are as follows, and candidates can choose the book that meets their knowledge and prepare accordingly.

  •   Introduction to Switching Theory and Logic Design – Fredriac J. Hill, Gerald R. Peterson, 3rd Ed, John Wiley Sons Inc.
  • Digital Fundamentals – A Systems Approach – Thomas L. Floyd, Pearson, 2013.
  • Digital Logic Design – Ye Brian and Holds Worth, Elsevier.
  • Fundamentals of Logic Design- Charles H. Roth, Cengage Learning, 5th, Edition, 2004.
  • Digital Logic Applications and Design- John M. Yarbrough, Thomson Publications, 2006.
  • Digital Logic and State Machine Design – Comer, 3rd, Oxford, 2013.
  • Switching and Finite Automata Theory- Zvi Kohavi & Niraj K. Jha, 3rd Edition, Cambridge.
  • Digital Design- Morris Mano, PHI, 3rd Edition.
  • Modern Digital Electronics by RP Jain, TMH
  • Microelectronics by Milliman MH edition.
  • Switching Theory and Logic Design by Hill and Peterson Mc-Graw Hill TMH edition.
  • Switching Theory and Logic Design by A. Anand Kumar

STLD Curriculum

The best way to make your preparation effective is with an initial idea and an outline of the STLD Syllabus. Keeping in mind every student’s requirements, we have provided a detailed view of the STLD curriculum.

STLD Course Curriculum will give students a clear idea of what to study, and the unit-wise break up gives topics under each unit carefully and allot time to each topic.

Students must cover all the topics before attempting the STLD exam so that the paper is reasonably comfortable at the time of the exam. Candidates must ensure awareness of the STLD Syllabus as it prevents you from wasting unnecessary time on redundant topics.

The updated unit-wise breakup of the STLD Syllabus is as follows-

Unit Topics
UNIT I: i) Representation of numbers of different radix, conversation from one radix to another radix, r-1’s compliments and r’s compliments of signed members, problem solving. ii) 4 bit codes, BCD, Excess-3, 2421, 84-2-1 9’s compliment code etc., iii) Logic operations and error detection & correction codes; Basic logic operations -NOT, OR, AND, Universal building blocks, EX-OR, EX-NOR – Gates, Standard SOP and POS, Forms, Gray code, error detection, error correction codes (parity checking, even parity, odd parity, Hamming code) NAND-NAND and NOR-NOR realizations.
UNIT II- Boolean theorems, principle of complementation & duality, De-morgan theorems, minimization of logic functions using Boolean theorems, minimization of switching functions using K-Map up to 6 variables, tabular minimization, problem solving (code-converters using K-Map etc..).
UNIT III- Design of Half adder, full adder, half subtractor, full subtractor, applications of full adders, 4-bit binary subtractor, adder-subtractor circuit, BCD adder circuit, Excess 3 adder circuit, look-a-head adder circuit, Design of decoder, demultiplexer, 7 segment decoder, higher order demultiplexing, encoder, multiplexer, higher order multiplexing, realization of Boolean functions using decoders and multiplexers, priority encoder, 4-bit digital comparator.
UNIT-IV- PROM, PAL, PLA-Basics structures, realization of Boolean function with PLDs, programming tables of PLDs, merits & demerits of PROM, PAL, PLA comparison, realization of Boolean functions using PROM, PAL, PLA, programming tables of PROM, PAL, PLA.
UNIT V- Classification of sequential circuits (synchronous and asynchronous); basic flip-flops, truth tables and excitation tables (nand RS latch, nor RS latch, RS flip-flop, JK flip-flop, T flip-flop, D flip-flop with reset and clear terminals). Conversion from one flip-flop to flip-flop. Design of ripple counters, design of synchronous counters, Johnson counter, ring counter. Design of registers – Buffer register, control buffer register, shift register, bi-directional shift register, universal shift register.
UNIT VI- Finite state machine; Analysis of clocked sequential circuits, state diagrams, state tables, reduction of state tables and state assignment, design procedures. Realization of circuits using various flip-flops. Meelay to Moore conversion and vice-versa.

List of STLD Important Questions

Candidates studying STLD can go through the list of essential questions mentioned below for the STLD course programme. All the given review questions aim to help the candidates to excel in the examination.

  1. What is the difference between Latch And Flip-flop?
  2. What is the binary number system?
  3. State De Morgan’s Theorem?
  4. Define Digital System?
  5. What is meant by a bit?
  6. What is the best Example of a Digital system?
  7. How many types of number systems are there?
  8. What is the Logic gate?
  9. What are the basic Logic gates?
  10. Which gates are called Universal gate and what are its advantages?
  11. What are the applications of the octal number system?
  12. What are the fundamental properties of Boolean algebra?
  13. What are Boolean algebra and Boolean expressions?
  14. What is meant by K-Map or Karnaugh Map?
  15. Name the two forms of Boolean expression?
  16. What are Minterm and Maxterm?
  17. Write down the Characteristics of Digital ICs?
  18. What are the limitations of the Karnaugh Map?
  19. What are the advantages and disadvantages of the K-Map Method?
  20. What are the advantages and disadvantages of Quine-MC Cluskey method?

FAQs on STLD Notes

Question 1.
Express the Boolean function F = A + B´C in a sum of minterms

The function has three variables, A, B, and C. The first term A is missing two variables; therefore A = A(B+B’) = AB+AB’

This is still missing one variable C: A = (AB+AB’) (C+C’) = ABC+ABC’+AB’C+AB’C’

The second term B´C is missing one variable: B’C = B’C (A+A’) = AB’C+A’B’C

F = A+B’C = ABC+ABC’+AB’C+AB’C’ + AB’C+A’B’C

But ABC appears twice, and according to theorem 1

F = ABC+ABC’+AB’C+AB’C’+A’B’C = m7+m6+m5+m4+m1 = Σ( 1,4,5,6,7)

Question 2.
Describe the differences between PLA and PAL


  • PLA has both programmable AND and OR planes whereas PAL has only programmable AND planes and OR plane is fixed
  • PLA has more flexibility in the logic circuit function implementation than PAL
  • PAL is simpler to manufacture than PLA
  • PLA has reduced speed performance
  • PAL devices are manufactured in a smaller size.

Drawbacks of PLA †

  • PLA was hard to be implemented †
  • PLA reduced the speed performance of circuits. „

Advantage of PAL †

  • Simple to manufacturers † Less expensive †
  • Better performance „

The disadvantage of PAL †

  • Not flexible as compared PLA, because OR plane is fixed.

Question 3.
What you mean by weighted code?


  • Weighted binary codes are those binary codes which obey the positional weight principle. Each position of the number represents a specific weight. Several systems of the codes are used to express the decimal digits 0 through 9. In these codes, each decimal digit is represented by a group of four bits.
  • In the example below, 100101, which is a binary base 2 number, is converted to a decimal (base 10) number.100101 = Binary (base 2) number 543210 = positional weights (1 x 2^5) + (0 x 2^4) + (0 x 2^3) + (1 x 2^2) + (0 x 2^1) + (1 x 2^0) =32 + 0 + 0 + 4 + 0 + 1 = 3737base10 = decimal conversion Other weighted methods include BCD and 2421, each of which uses a similar formula to assign weights and convert to decimal

Question 4.
What is the race condition? How it can be avoided?

A race condition is a result of poor design for a latch or flip-flop. It denotes a condition in which the data and clock are changing at the same time and the result depends on which one wins.

In rare cases, the data can be exactly on the threshold between a 0 and 1 and when the clock changes, the output actually stays between a 0 and 1 for a while (for example in a 5V system the output may stay around 2.5 volts for a short time (microseconds, maybe). When this happens the output is said to be ‘metastable’. This could have serious effects on the operation of the system and worse, could be virtually impossible to duplicate and thus very hard to find and fix.

This same problem can exist at inputs to a logic gate and produce unwanted ‘glitches’.

In order to prevent these design flaws, the designer needs to do a ‘worst case timing analysis’ on all the logic. This analysis uses propagation delays, rise and fall times, threshold points, etc. to calculate timings. He must do both minimum and maximum times for each device and choose the worst case combinations. In a large system, this can be very time consuming but there are tools to aid in this analysis.

Power gating is used to simply turn the clock on and off (or gate the clock) to sections of logic that aren’t in use for periods of time. This results in a reduction in power.


The information on STLD Notes is genuine and reliable and the above mentioned Books and Study Materials aim to help and enhance student’s knowledge and understanding of the subject during preparations and at the time of examination. Students can refer and practice from the provided STLD Books, Study Materials, and Important Questions from this article.