IC Integrated circuits ppt for undergraduate course.pptx

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About This Presentation

Integrated circuits


Slide Content

1 Basics of Electrical and Electronics Engineering Course Code: ECE1PM01A

UNIT-IV Introduction to Integrated Circuits 2

Contents: Introduction to Integrated Circuits: Analog Integrated circuits, Basics of OPAMP: study of parameters of IC 741, inverting and non-inverting amplifier, Digital integrated circuits: Logic Gates, Boolean algebra, Combinational logic Circuits, De-Morgan’s theorems, SOP, POS, K- map, Half Adder, Full Adder, flip-flops: RS flip flop, J-K flip flop, D flip flop, shift registers (12L) 3

Integrated Circuits Integrated circuit or IC or microchip or chip It is a microscopic electronic circuit array formed by the fabrication of various electronic components Components (resistors, capacitors, transistors,)are placed on semiconductor material (silicon) wafer It can perform operations similar to the large discrete electronic circuits made of discrete electronic components 4

IC- Integrated circuit ICs have three key advantages over digital circuits built from discrete components Small size ICs are much smaller , both transistors and wires are shrunk to micrometer sizes, compared to the centimeter scales of discrete components High speed Communication within a chip is faster than communication between chips on a PCB (Printed Circuit Board) Low power consumption Logic operations within a chip take much less power 5

6 IC Packaging Basic types of IC packages The metal can or transistor pack : chip is encapsulated in a metal or plastic case. Available with 3,5,8,10 or 12 pins LM117 (voltage regulator) has 3 pins Power op-amps, audio power amplifiers have 5 pins General purpose op-amps come in 8,10 or 12 pins The flat pack : the chip is enclosed in a rectangular ceramic case with terminal leads extending through the sides and ends. Comes with 8, 10, 14 or 16 pins The dual-in-line package (DIP): chip is mounted inside a plastic or ceramic case Most widely used Available in 12, 14, 16 and 20 pins

7 Manufacturer’s Designation for ICs Each manufacturer uses a specific code and assigns a specific type number to the ICs it produces. Examples are- Fairchild Analog Devices AD Atmel AT National Semiconductor LM Motorola MC Signetics NE Texas Instruments CA/CD  

Example of Analog IC Operational Amplifier 8

Operational Amplifier: OP-AMP Linear Integrated Circuit Linear– Output signal varies according to the input signal Integrated – all components are fabricated on a single chip Direct coupled high gain amplifier Versatile device – amplifies ac as well as dc signals Originally designed for computing mathematical functions as addition, subtraction, multiplication and division, hence the name U sed for a variety of applications such as ac and dc signal amplification, active filters, oscillators, comparators, regulators, etc. 9

Op-amp IC Pinout diagram 10

Block diagram of op-amp 11

Internal Diagram of Op-Amp 12

Stages of internal block diagram Input Stage - The input stage is a Dual input balanced output differential amplifier. The two amplifiers are applied at inverting or non inverting terminals. This stage provides most of voltage gain of the op-amp and decides input resistance value R1. Intermediate Stage - It is driven by output of the input stage. This stage is dual input unbalanced output differential amp. This stage provides additional voltage gain to the input signals. 13

Stages of internal block diagram Level shifting stage - This is third stage in the block diagram of op-amp. Due to direct coupling between first two stage the input of level shifting stage is an amplifying system with non-zero DC level. Level shifting stage is used to bring this DC level to a zero volt with respect to ground. Output Stage - This is normally complementary output stage. It increases magnitude of voltage and rises the current supplying capacity of the op-amp. It also provides low output resistance. The output stage is a push pull of two transistors. 14

Ideal Op-amp and Practical Op-amp Circuit 15

Op-Amp Parameters 1. Open-loop voltage gain, Go 2. Input impedance, Zin(Ω) 3. Output impedance, Zo(Ω) 4. Input Offset current, Ios ( nA ) 5. Input Bias current, I BIAS ( nA ) 6. Input Offset voltage, Vos (mV) 7. Slew rate, SR (V/ μs ) 8. CMRR 9. SVRR / PSRR 10 Gain Bandwidth product 16

Op-Amp Parameters Maximum Output Voltage Swing (V O(p-p) ) With no input signal, the output of an opamp is ideally 0 V. When an input signal is applied, the ideal limits of the peak-to-peak output signal are Vcc . In practice, however, this ideal can be approached but never reached. It varies with the load connected to the op-amp and increases directly with load resistance. For example, the Fairchild KA741 datasheet shows a typical Vo(p-p) of 13V for Vcc = 15V when RL = 2K Ω and Vo(p-p) increases to 14V when RL = 10K Ω . 17

Op-Amp Parameters Open-loop voltage gain The open-loop voltage gain, A ol , of an op-amp is the internal voltage gain of the device and represents the ratio of output voltage to input voltage when there are no external components. The open-loop voltage gain is set entirely by the internal design. Open-loop voltage gain can range up to 200,000 (106 dB) and is not a well-controlled parameter. Datasheets often refer to the open-loop voltage gain as the large-signal voltage gain. 18

Op-Amp Parameters Input offset voltage The ideal op-amp produces zero volts out for zero volts in. In a practical op-amp, however, a small dc voltage, V OUT(error), appears at the output when no differential input voltage is applied. Its primary cause is a slight mismatch of the base-emitter voltages of the differential amplifier input stage of an op-amp. The input offset voltage, V OS , is the differential dc voltage required between the inputs to force the output to zero volts. Typical values of input offset voltage are in the range of 2 mV or less. In the ideal case, it is 0 V. 19

Op-Amp Parameters Input bias current T he input terminals of a bipolar differential amplifier are the transistor bases and, therefore, the input currents are the base currents. The input bias current is the dc current required by the inputs of the amplifier to properly operate the first stage. By definition, the input bias current is the average of both input currents and is calculated as follows: 20

Op-Amp Parameters Input offset current Ideally, the two input bias currents are equal, and thus their difference is zero. In a practical op-amp, however, the bias currents are not exactly equal. The input offset current, I OS , is the difference of the input bias currents, expressed as an absolute value. I OS = | I 1 – I 2 | Typical value is 200 nA 21

Op-Amp Parameters Input Impedance The differential input impedance is the total resistance between the inverting and the noninverting inputs, as illustrated in Figure It is measured by determining the change in bias current for a given change in differential input voltage. 22

Op-Amp Parameters Output Impedance The output impedance is the resistance viewed from the output terminal of the op-amp, as indicated in Figure 23

Op-Amp Parameters Slew rate The slew rate is the maximum rate of change of output voltage for a step input voltage.  The slew rate makes the output voltage to change at a slower rate than the applied input.  Max rate of change of output voltage with time. i.e. dv/dt (max) or ΔV/ Δt max expressed in (volts/µs) . Slew rate is usually measured in the unity gain non-inverting amplifier configuration Typically it is 0.5 V/ μs 24

25 Slew rate

Op-Amp Parameters SVRR (Supply Voltage Rejection Ratio) or Power Supply Rejection Ratio (PSRR) Power-supply rejection ratio PSRR is the ratio of the change in input offset voltage to the corresponding change in power-supply. The PSRR is expressed in mV/V or dB   PS RR = ΔVos / ΔV   26

Op-Amp Parameters Common Mode Rejection Ratio­ (CMRR) The output signal due to the common mode input voltage is zero, but it is nonzero in a practical device. CMRR is the measure of the amplifier's ability to reject common mode signals The output voltage is proportional to the difference between the voltages applied to its two input terminals.   When the two input voltages are equal, ideally the output voltage should be zero. It is a metric used to quantify the ability of the device to reject common-mode signals, i.e. those that appear simultaneously and in-phase on both inputs. 27

A signal applied to both input terminals of the op-amp is called as common-mode signal. Usually it is an unwanted noise voltage. CMRR is defined as the ratio of the open loop differential voltage gain A ol to the common mode voltage gain A cm CMRR = A ol / A cm CMRR=20 log [ A ol / A cm ]  dB 28 Common Mode Rejection Ratio­ (CMRR)

Op-Amp Parameters 29 Gain Bandwidth Product It is the bandwidth of the op-amp when the voltage gain is 1 Typically it is 1 MHz Also called closed-loop bandwidth, unity gain bandwidth and small-signal bandwidth GBP=Av × f Where: GBP = op amp gain bandwidth product  Av = voltage gain  f = cutoff frequency (Hz) 

Op Amp Parameters Parameter values for op-amps IDEAL PRACTICAL Open-loop voltage gain, Go(V/V) INF 2,00,000 2. Input impedance, Zin (Ω) INF 2 MΩ 3. Output impedance, Zo (Ω) 75 Ω 4. Input Offset current, Ios ( nA ) 20 nA 5. Input Bias current, I BIAS ( nA ) 80 nA 6. Input Offset voltage, Vos (mV) 2 mV 7. Slew rate, SR (V/ μs ) INF 0.5 V/microsec 8. CMRR INF 90 dB 9. SVRR / PSRR INF 96 dB 10 Gain Bandwidth product INF 1 MHz 30

What is negative feedback? Negative feedback is the most useful concepts in OPAMP applications. It is the process whereby a portion of the output voltage of an amplifier is returned to the input with a phase angle that opposes the input signal. 31

Negative Feedback / Closed Loop configuration 32 Negative feedback is illustrated in the Figure. The inverting input effectively makes the feedback signal 180° out of phase with the input signal.

Why Use Negative Feedback? The inherent open-loop voltage gain of a typical op-amp is very high (usually greater than 100,000). Therefore, an extremely small input voltage drives the op-amp into its saturated output states. In fact, even the input offset voltage of the op-amp can drive it into saturation. For example, assume V in = 1 mV and A ol = 100,000. Then: V in A ol = (1 mV)(100,000) = 100 V Since the output level of an op-amp can never reach 100 V, it is driven deep into saturation and the output is limited to its maximum output levels, i . e. Vcc . With negative feedback, the closed loop voltage gain ( A cl ) can be reduced and controlled so that the op-amp can function as a linear amplifier. In addition to providing a controlled, stable voltage gain, negative feedback also provides for control of the input and output impedances and amplifier bandwidth. 33

Closed-Loop Voltage Gain, Acl The amplifier configuration consists of the op-amp and an external negative feedback circuit that connects the output to the inverting input . The closed-loop voltage gain is the voltage gain of an op-amp with external feedback. The closed-loop voltage gain is determined by the external component values and can be precisely controlled by them. 34

Virtual short and Virtual ground Voltage between inverting and non-inverting terminals of OP-AMP is output voltage divided by open loop gain of OP-AMP. Open loop gain being very large, this voltage is very small. Practically zero. This is virtual short. Both input terminals will be at the same potential. In other words they are virtually shorted to each other. Virtual ground concept is NOT valid for positive feedback or open loop operation of OPAMP.   35

Virtual Ground If the non-inverting (+) terminal of OP-AMP is connected to ground, then due to the "virtual short" existing between the two input terminals, the inverting (-) terminal also be at ground potential. hence it is said to be as "virtual ground". The input impedance (Ri) of an OP-AMP is ideally infinite. Hence current "I" flowing from one input terminal to the other will be zero. 36

Inverting Amplifier An op-amp connected as an inverting amplifier with a controlled amount of voltage gain is shown in Figure The input signal is applied through a series input resistor Ri to the inverting (-) input. Also, the output is fed back through Rf to the same input. The noninverting (+) input is grounded. 37

Inverting Amplifier Since there is no current at the inverting input, the current through Ri and the current through Rf are equal, as shown in Figure I in = I f 38 FIGURE: Virtual ground concept and closed loop voltage gain development for the inverting amplifier.

Inverting Amplifier 39 The closed-loop gain is independent of the op-amp’s internal open-loop gain.

Numerical 40

Exercise 41 Acl = -12.5

Noninverting Amplifier An op-amp connected in a closed-loop configuration as a noninverting amplifier with a controlled amount of voltage gain is shown in Figure. The input signal is applied to the noninverting (+) input. The output is applied back to the inverting input through the feedback circuit (closed loop) formed by the input resistor Ri and the feedback resistor Rf. This creates negative feedback as: Resistors Ri and Rf form a voltage-divider circuit, which reduces Vout and connects the reduced voltage Vf to the inverting input. 42 The feedback voltage is expressed as

Noninverting Amplifier 43 Fig. Differential input, V in - V f . Then applying basic algebra,

Noninverting Amplifier 44 Since the overall voltage gain of the amplifier in is Vout /Vin, it can be expressed as

Closed loop Gain Notice that the closed-loop voltage gain is not at all dependent on the op-amp’s open-loop voltage gain under the condition Aol B >> 1 Example : Aol = 100000 , B<1 The closed-loop gain can be set by selecting values of Ri and Rf 45

Numerical 46 Practice problem: Find Ri to get gain as 30 with the same value of Rf.

Determine closed loop gain of each amplifier Ans. 11 101 47.8 23 47 Exercise

Find Rf Value for the each op amp. Ans. 49K 3M 84K 165K 48 Exercise

If signal voltage is 10mVrms, find the output voltage. Ans. a)10mVrms, in phase b) -10mVrms,out of phase c) 223 mVrms , in phase d) -100 mVrms , out of phase 49 Exercise

Exercise 50 In the circuit given below, if R 2 = 1 K & R 1 = 10 K & input in 0.1V what will be the output Ans. Acl = - R1/R2 = 10 Vout = Vin * Acl Vou = -1V, out of phase  

Exercise 51 Calculate the input voltage for this circuit if V o = –11 V. Ans. Vin = 1.1 V

An OP-AMP is used in inverting mode with R 1 = 1K Ω and R F = 15K Ω . Vcc = +/- 15V. Calculate the output voltage for i ) Vi= 150 mV ii) Vi= 1V Solution: A= -R F /R 1 = -(15 K Ω / 1K Ω ) = -15 Vi= 150 mV Vo= (-15 × 150 mV) = -0.225V ii) Vi= 1V Vo= (-15 × 1V) = -15V 52 Exercise

Digital Electronics It uses Binary Digits 0 and 1 Each of the two digits in the binary system, 1 and 0, is called a bit, Two different voltage levels are used to represent the two bits. 1 - is represented by the higher voltage, which will be referred as a HIGH, 0 - is represented by the lower voltage level, which will be referred as a LOW. This is called positive logic and will be used throughout the topic.

Logic Level ranges or Voltage for a digital circuits

Basic Logic Functions In the 1850s, the Irish logician and mathematician George Boole developed a mathematical system for formulating logic statements with symbols so that problems can be written and solved in a manner similar to ordinary algebra The term logic is applied to digital circuits used to implement logic functions. Three basic logic functions - NOT, AND, and OR Logic functions are indicated by standard symbols shown below The inputs are on the left of each symbol and the output is on the right. A circuit that performs a specified logic function (AND, OR) is called a logic gate. AND and OR gates can have any number of inputs. The basic logic functions and symbols

Example 1 Determine output X: Write logical expression and output waveform

Logic Function NAND The NAND gate is the same as the AND gate with the inverted output. The Boolean expression for the output of a 2-input NAND gate is

NOR Gate Logic Expressions for a NOR Gate: ->

EX-OR Gate Logic Expressions for a XOR Gate: Truth Table T here are two special gates, i.e., Ex-OR and Ex-NOR. These gates are not basic gates in their own and are constructed by combining with other logic gates. 

EX-OR Gate

OR Gate AND Gate

Digital Circuits Basically, Digital Circuits are divided into two broad categories Combinational circuits Combinational Circuit  is the type of  circuit  in which output depend upon the input present at that particular instant. Sequential circuits Sequential circuit  is the type of  circuit  where output at any instant of time depend upon the current input as well as on the previous input/output. It consists of memory element

Combinational Logic Circuit Representation

Combinational Logic Circuits Combinational logic circuits have no feedback, and any changes to the signals being applied to their inputs will immediately have an effect at the output. It has no “memory”, “timing” or “feedback loops”. The three main ways of specifying the function of a combinational logic circuit are: Boolean Expression  – This forms the algebraic expression showing the operation of the logic circuit Truth Table  – Shows all the output states in tabular form for each possible combination of input variable Logic Diagram  – This is a graphical representation of a logic circuit

Combinational Logic Circuit Boolean expression A(B + C) Truth Table  Logic Diagram 

Boolean Algebra Boolean algebra is the mathematics of digital logic Commutative Laws : The commutative law of addition for two variables is written as The commutative law of multiplication for two variables is

Associative Laws The associative law of logical addition is written as follows for three variables: The associative law of logical multiplication is written as follows for three variables

Distributive Law The distributive law is written for three variables as follows: A(B + C) = A.B + A.C      (OR Distributive Law) A + (B.C) = (A + B).(A + C)     (AND Distributive Law)

Basic rules of Boolean algebra Rule 1 Rule 2

Rule 8 Rule 7 Rule 6 Rule 5 Rule 4 Rule 3

Rule 9 Equivalence

Equivalence

De Morgan’s theorem 1. The complement of a product of variables is equal to the sum of the complements of the variables. OR The complement of two or more ANDed variables is equivalent to the OR of the complements of the individual variables. 2. The complement of a sum of variables is equal to the product of the complements of the variables. OR The complement of two or more ORed variables is equivalent to the AND of the complements of the individual variables.

De Morgan’s Theorem 1 A · B = A + B EQUAL NAND = Bubbled OR

De Morgan’s Theorem 2 A + B = A · B EQUAL NOR = Bubbled AND

De Morgan’s Law

NAND gate as universal logic gate

NOR gate as universal logic gate

Exercise

Exercise- Solution = X .Y . Z = W + X + Y + Z = ( A + B + C ) + D = A B C + D = A B C . D E F = (A + B + C) . ( D + E + F )

Standard Forms of Boolean Expressions Sum-of-products form (SOP) Product-of-sums form (POS) The Sum-of-Products (SOP) Form: An SOP expression can be implemented with one OR gate and two or more AND gates.

The Product-of-Sums (POS) Form When two or more sum terms are multiplied, the resulting expression is a product-of-sums (POS). Implementing the POS expression simply requires AND ing the outputs of two or more OR gates

Construct SOP form expression from a Truth Table

Construct POS form expression from a Truth Table F = (A + B + C) (A + B + C) (A + B + C) (A + B + C) (A + B + C)

Canonical SOP form and POS form Each individual term in canonical SOP form is called as minterm and in canonical POS form as maxterm

Shorthand form of canonical SOP using minterms F = m1 + m3 + m5 F = Σ m (1, 3, 5)

Shorthand form of canonical POS using maxterms F = (A + B + C) (A + B + C) (A + B + C) (A + B + C) (A + B + C) F = M0 M2 M4 M6 M7 F = Π M (0, 2, 4, 6, 7)

Simplification of Boolean expression The required Boolean results are transferred from a  truth table  onto a two-dimensional grid where, in Karnaugh maps, the cells are ordered in  Gray code , [6] [4]  and each cell position represents one combination of input conditions, while each cell value represents the corresponding output value. Optimal groups of 1s or 0s are identified, which represent the terms of a  canonical form  of the logic in the original truth table. [7]  These terms can be used to write a minimal Boolean expression representing the required logic.

The Karnaugh Map( K map) Technique A Karnaugh map technique provides a graphical, systematic method for simplifying Boolean/ logic expressions Karnaugh map is an array of cells in which each cell represents a binary value of the input variables K-map produce the simplest SOP or POS expression possible, known as the minimum expression The information contained in the truth table or available in SOP/ POS form is represented on K map Karnaugh maps can be used easily used as a tool to simplify expressions with two, three, four , five variables

K-maps K-maps adjacencies wrap around edges Wrap from first to last column Wrap top row to bottom row Numbering scheme is based on Gray–code (only a single bit changes in code for adjacent map cells K-maps are hard to draw and visualize for more than 4 dimensions, and virtually impossible for more than 6 dimensions

Two variable K-map Three variable K-map m interms / maxterms written inside the corresponding cell in the K-map minterms Maxterms

Procedure for Obtaining Simplified Boolean equation from K-map Identify adjacent ones for grouping (Group size 2, 4, 8 ) See the values of the variables associated with these cells Only one variable will be different and it gets eliminated Other variables will appear in ANDed form in the term, it will be in the uncomplemented form if it is 1 and in complemented form if it is 0. Determine the term corresponding to each group of adjacent ones. These terms are ORed to get the simplified equation in SOP form.

K-map examples (2 variable) A’ is A bar and B’ is B bar

K Map – 2 variables examples

K Map – 2 variables examples

K-map examples (3 variable) X YZ

S olution is : F =  yz   +  xz   +  xy K-map examples (3 variable)

Example: F = x’y’z + x’yz + x’yz ’ + xy’z ’ + xy’z + xyz Solution: The equation has six minterms . So, enter 1’s at appropriate positions in the K-Map S olution is: F =  z  +  x’y   +  xy ’ K-map examples (3 variable)

K-map examples (3 variable) Adjacent cells for grouping

K-map examples (3 variable)

Redundant Groups A redundant group is one whose all the 1’s have been consumed by other groups. So, there is no need to form such group. Whenever you see that all 1’s of a group have been exhausted, simply ignore that group. y = x’z + xy ’ xy ’

K-map examples (3 variable) 1. F = Σ m( 0, 1, 4, 5, 6 ) F = Y’ + X Z’ 2. F = Σ m( 1, 2, 5, 7 ) F = X’ Y Z’ + X Z + Y’ Z

Arithmetic Circuits: Half Adder A half-adder is an arithmetic circuit block that can be used to add two 1 bit numbers. Such a circuit thus has two inputs that represent the two bits to be added and two outputs , with one producing the SUM output and the other producing the CARRY . Possible input combinations and the corresponding outputs are as given in the truth table. The Boolean expressions for the SUM and CARRY outputs are given by the following equations.

Half Adder Truth Table , Kmap , Realization Input Output A B S C 1 1 1 1 1 1 1 Sum = S Carry = C

Full Adder A full adder circuit is an arithmetic circuit block that can be used to add three bits to produce a SUM and a CARRY output. Such a building block is needed in order to add binary numbers with a large number of bits. The full adder circuit overcomes the limitation of the half-adder, which can be used to add two bits only

Full Adder Sum = S Carry = CR S = A’B’C + A’BC’+AB’C’+ABC = A’(B’C + BC’) + A(B’C’ + BC) = A (B C) + A (B C ) = A B C CR = AB + BC + AC S = ∑m(1,2,4,7) C = ∑m(3,5,6,7)

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Full Adder

Sequential Logic Circuit Sequential logic  is a type of logic circuit whose output depends not only on the present value of its input signals but on the sequence of past inputs, the input history. Sequential logic is combinational logic with memory. Sequential logic circuits are classified in 2 categories Synchronous Asynchronous

Clock Pulse- CK =0 or CK=1 A Synchronization is achieved by the timing device known as system clock which generates a periodic train of clock pulses shown in figure. The outputs are affected with the application of clock pulse, CK.

SR Latch (1-Bit Memory Cell )

SR Flip-Flop Block diagram Race Around

SR Flip flop Operation S.N. Condition Operation 1 S = R = 0 , CK=1 If S = R = 0 then output of NAND gates 3 and 4 are forced to become 1. Hence R' and S' both will be equal to 1. Since S' and R' are the input of the basic S-R latch using NAND gates, there will be no change in the state of outputs. 2 S = 0, R = 1, CK = 1 Since S = 0, output of NAND-3 i.e. R' = 1 and CK = 1 the output of NAND-4 i.e. S' = 0. Hence Q n+1  = 0 and Q n+1  bar = 1. This is reset condition. 3 S = 1, R = 0, CK = 1 Output of NAND-3 i.e. R' = 0 and output of NAND-4 i.e. S' = 1. Hence output of S-R NAND latch is Q n+1  = 1 and Q n+1  bar = 0. This is the set condition. 4 S = 1, R = 1, CK = 1 As S = 1, R = 1 and E = 1, the output of NAND gates 3 and 4 both are 0 i.e. S' = R' = 0. Hence the  Race  condition will occur in the basic NAND latch.

Truth Table of J-K Flip-Flop Fig: Block Diagram

D Flip-Flop If we use only middle two rows of SR or JK flip-flop, We obtain D Flip-flop.

Operation of D Flip-Flop S. No. Condition Operation 1 E = 0 Latch is disabled. Hence no change in output. 2 E = 1 and D = 0 If E = 1 and D = 0 then S = 0 and R = 1. Hence irrespective of the present state, the next state is Q n+1  = 0 and Q n+1  bar = 1. This is the reset condition. 3 E = 1 and D = 1 If E = 1 and D = 1, then S = 1 and R = 0. This will set the latch and Q n+1  = 1 and Q n+1  bar = 0 irrespective of the present state.

T Flip-Flop In JK flip-flop, if J=K, the resulting Flip-flop is called as T Flip-flop.

Operation of T Flip-Flop S.N. Condition Operation 1 T = 0, J = K = 0 The output Q and Q bar won't change 2 T = 1, J = K = 1 Output will toggle corresponding to every leading edge of clock signal.

Shift Register Register is a digital circuit with two basic functions: Data storage Data Movement A register can consist of one or more flip flops used to store and shift data Shift Registers are an important Flip-Flop configuration with a wide range of applications, including: Computer and Data Communications Serial and Parallel Communications Multi-bit number storage Sequencing Basic arithmetic such as scaling (a serial shift to the left or right will change the value of a binary number a power of 2) Logical operations

Data Transfer Methods/ Modes 1. SISO: Serial In, Serial Out How many clock edges are required for each operation? 10110 10110 10110 10110 10110 10110 10110 10110 2. SIPO: Serial In, Parallel Out 3. PISO: Parallel In, Serial Out 4. PIPO: Parallel In, Parallel Out 2n-1 clock cycle n clock cycle n clock cycle 1 clock cycle

SISO Flip-Flop Shift Register A Serial In Serial Out shift register has a single input and a single output D Q Q D Q Q D Q Q Input Output CLK

SIPO Flip-Flop Shift Register Serial In Parallel Out shift register has a single input and access to all outputs D Q Q D Q Q D Q Q Input Output Output Output CLK

PIPO Flip-Flop Shift Register Parallel In Parallel Out register has the simplest configuration. It represents a memory device. D Q Q Input Output D Q Q Output D Q Q Output Input Input CLK

PISO Flip-Flop Shift Register Parallel In Serial Out shift register requires additional gates, and the parallel input must revert to logic low. Input D Q 1 Q Input Output Input D Q Q D Q Q

Additional links for more information: http://www.ee.surrey.ac.uk/Projects/CAL/digital-logic/gatesfunc/ https://www.electronicshub.org/half-adder-and-full-adder-circuits/ https://youtu.be/kt8d3CYWGH4 https://youtu.be/HZg7fNu-l24

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