Four-bit Parallel Adder Ripple Adder

Duration: 7 min

This video lesson is available to enrolled students.

Return to /learn/TPSC-ASSISTANT-TECHNICAL-OFFICER/digital-logic/combinational-circuit/cla-arithmetic-logic/asset-four-bit-parallel-adder-ripple-adder after enrolling

Inside: a video lesson and guided study material.

Module outline

  1. About Course: About the Course
  2. Paper 2 | Digital Logic: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation, Floating Point Rep
  3. Paper 2 | Computer Organization And Architecture: Basics of COA, Cache Memory Organization, Input Output Organisation, Pipelining, Control Unit Design, Instr Formats & Modes, Programming the Basic Computer
  4. Paper 2 | Analog And Digital Communication: Introduction to Communication Systems & Random Signals, Analog Communication Systems, Information Theory & Digital Communication Fundamentals, Digital Modulation & Detection Techniques, Error Control, Synchronization & Multiple Access Techniques
  5. Paper 2 | Programming in C: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling
  6. Paper 2 | Data Structures And Programming: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, Java, OOPS with C++, Java Fundamentals, Array, String, IO & References
  7. Paper 2 | Algorithms: Algorithm Analysis, Sorting Algorithms, Time Complexity Analysis, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos
  8. Paper 2 | Compiler Design: Intro to Compilers, Lexical Analysis, Grammar & CFG, Syntax Analysis: Top-Down, Syntax Analysis: Bottom-Up, Semantic Analysis & SDT, Intermediate Code Gen, Code Optimization, Run Time Environment
  9. Paper 2 | Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management, Unix OS, Linux OS
  10. Paper 2 | Databases: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, Relational Algebra, SQL, Relational Calculus, File Organization & Indexing, Transaction Management, Concurrency Control
  11. Paper 2 | Information Systems and Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
  12. Paper 2 | Computer Networks: Introduction to CN, Data Communication, DLL: Access Control, DLL: Flow Control, DLL: Error Control, DLL: Framing, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Net Layer:Routing Protocol, Transport Layer Services, TL: Congestion & UDP, Application Layer, Hardware Basics
  13. Paper 2 | Internet & Web Technologies: Website, Browser & Services, Internet Fundamentals, Web Design & Development, Protocols & Services, Web Publishing & Hosting, Server Side & Security, Emerging Technologies, HTML Basics, JavaScript-Basics, CSS, XML, HTML5
  14. Paper 2 | Cyber Security And Emerging Technologies: Emerging Tech Trends
  15. Paper 2 | Cloud Technology: Cloud Computing
  16. Paper 2 | Probability and statistics: Probability, Statistics
  17. Paper-1 English: Vocabulary, Preposition, Articles, Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions), Sentence Re-arrangements (Para Jumbles) (Narrative Sequencing), Sentence Correction (Error Correction), Sentence Completion (Fill in the blanks), Cloze Test (Cloze Passage), Sentence Construction
  18. Paper 1 General Mental Ability & Logical reasoning: Ratio and Proportion (Ratios), Divisibility Rules, Data Interpretation, Mixture and Alligation, Permutation and Combination, Logarithm, Number System, HCF LCM, Sequence and Series (Series), Speed Time and Distance, Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Data Sufficiency, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Percentage, Average, Powers and Exponents (Surds and Indices), Algebra, Profit and Loss, Simple Interest and Compound Interest, Time and Work, Pipe and Cistern, Mensuration and Geometry, Mental Ability, Age Problems, Partnership, Arithmetic, Speed Mathematics and Basic Mathematics, Syllogisms, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Seating Arrangements, Blood Relations, Directions (Direction Test), Analytical Reasoning (Counting Figures Reasoning), Puzzle Solving (Puzzles), Calendar, Clock, Cubes & Dices, Selection Decision Table (Decision Making), Logical Sequence Of Words, Venn Diagram, Analogy
  19. Paper-1 General Knowledge & Current Affairs: State Wise GK, History, Geography, GK- Current Affairs, Static General Knowledge
  20. Full Length Mock Test:
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

The lecture focuses on the design and functionality of a four-bit parallel binary adder, commonly referred to as a ripple adder. The instructor begins by establishing the fundamental building block: the full adder, which adds two 1-bit numbers and a carry-in. He explains that to perform addition on multi-bit binary numbers, multiple full adders must be employed in a specific configuration. The visual aid displays a schematic with four columns representing the bit positions, labeled A3 through A0 and B3 through B0 for the two operands. The outputs are labeled S3 through S0 for the sum bits. The instructor emphasizes the carry propagation, showing how the carry-out from one stage becomes the carry-in for the next higher-order stage, labeled C4 through C0. He physically points to and circles the input rows to reinforce the parallel input structure. This sets the stage for understanding how digital circuits handle arithmetic operations beyond single bits.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The instructor introduces the concept of a four-bit parallel binary adder. He explains that while a single full adder is capable of adding two 1-bit numbers and a previous carry, adding numbers with more than one bit requires additional full adders. He points to a diagram showing four columns of inputs (A3, A2, A1, A0 and B3, B2, B1, B0) and outputs (S3, S2, S1, S0). He highlights the carry signals C4, C3, C2, C1, and C0, explaining their role in the addition process. He circles the rows of inputs A and B to show they are applied in parallel. He specifically points out the carry outputs C4, C3, C2, C1, and C0, indicating the flow of information between stages.

  2. 2:00 – 5:00 02:00-05:00

    The instructor transitions to a block diagram representation of the adder. He explains that the four full adders are connected in cascade, where the carry output of each adder is connected to the carry input of the next higher-order adder. He notes that the least significant bit stage uses a Half Adder, while the others use Full Adders. He writes binary numbers "1011" and "1101" above the inputs to demonstrate a specific addition example. He circles the Half Adder block and traces the carry path from C1 to C2 to C3 to C4, illustrating the ripple effect. He calculates the sum bits S0, S1, S2, S3 based on the example. He explicitly writes "1011" and "1101" on the board to show the inputs for the addition. He points to the carry lines C1, C2, C3, and C4 to show the direction of the ripple.

  3. 5:00 – 7:19 05:00-07:19

    The instructor discusses the scope for improvement in adders. He presents a slide comparing "Carry propagation delay" with "Look ahead Carry Generator". The slide uses illustrations of a slow person and a fast person to metaphorically represent the speed difference. He explains that the ripple adder suffers from delay because the carry must propagate through each stage sequentially. He then introduces the concept of modifying an adder to work as a subtractor, showing a diagram labeled "Adder/subtractor or ripple adder". This suggests a modification to the circuit to perform subtraction operations, likely using 2's complement. He mentions that the adder can be modified to work as a subtractor. He shows a diagram with Full Adders and a Half Adder again, implying the structure remains similar but with control logic for subtraction.

The video provides a comprehensive overview of the four-bit parallel binary adder. It starts with the theoretical basis of cascading full adders, moves to a practical block diagram with a specific binary addition example, and concludes by addressing performance limitations. The instructor clearly distinguishes between the ripple adder's sequential carry propagation and faster alternatives like the look-ahead carry generator. The final segment hints at the versatility of the adder circuit by introducing the adder/subtractor concept. The lecture effectively bridges the gap between basic logic gates and complex arithmetic circuits.

Loading lesson…