Experiment No.
:1
Objective:- Introduction to digital electronics lab-nomenclature of digital IC’s, study of the
data sheet, and concept Vcc and ground. Verification of the truth tables of logics gates using
TTL IC’s
Components Required:-
S. No. Name of Apparatus Specifications
1. Digital trainer Kits with Breadboard
2. IC 7432 Quad Two i/p OR Gate
IC 7408 Quad Two i/p AND Gate
IC 7404 Hex Inverter
IC 7400 Quad Two i/p NAND Gate
IC 7410 Triple Three i/p NAND Gate
IC 7402 Quad Two i/p NOR Gate
IC 7486 Quad Two i/p X-OR Gate
3. Connecting wires
Brief Theory:-
Gate: - Gate is a logical circuit, which can have ‘N’ no. inputs and only one output.
Integrated Circuit (I.C):- An integrated circuit has many components built on a single chip.
Generally logic gates ICs has 14 pin configurations. All the logic gates, which we have to study,
has an individual ICs which has a particular ICs number.
Truth Table: - It is a table which represents possible states combination of input and their
corresponding output.
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Nomenclature of digital IC’s-
74 stand For TTL Logic General Purpose
54 stand For TTL Logic Military Purpose.
74HC and 74HCT- High-speed CMOS (the “T” indicates TTL compatibility)
74AC and 74ACT- Advanced CMOS
74HC and 74AHCT- Advanced High-speed CMOS
The basic CMOS series for the 3.3V category and their designations are as follows:
74LV- Low-voltage CMOS
74LVC-Low-voltage CMOS
74ALVC-Advaced Low-voltage CMOS
In addition to the 74 series there is a 4000 series, which is an older, low-speed CMOS
technology that is still available, although in limited use. In addition to the “pure” CMOS
there is a series that combines both CMOS and TTL called Backmost. The basic BiCMOS
series and their designation are as follows.
74BCT-BiCMOS
74ABT-Advanced BiCMOS
74LVT-Low-voltage BiCMOS
74ALB-Advenced Low-voltage BiCMOS
74-standard TTL (no letter)
74S-Schottky TTL
74AS- Advanced Schottky TTL
74LS-Low-power Schottky TTL
74ALS-Advanced Low-power Schottky TTL
74F- Fast TTL
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Circuit Diagram:-
2 i/p NAND GATE: 3 i/p NAND GATE:
SN74LS00N (NAND GATE) SN74LS10N (THREE I/P NAND)
NOT GATE: 2 i/p AND Gate:
SN74 LS04N(NOT GATE) SN74LS08N (AND GATE)
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2 i/p OR Gate: 2 i/p XOR Gate:
SN74LS32N (OR GATE) SN74LS86N(X-OR GATE)
2 i/p NOR Gate:
SN74LS02N (NOR GATE)
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Procedure:- .
1. Place the IC on IC Trainer Kit.
2. Connect VCC and ground to respective pins of IC Trainer Kit. .
3. Connect the inputs to the input switches provided in the IC Trainer Kit.
4. Connect the outputs to the switches of O/P LEDs.
5. Apply various combinations of inputs according to the Truth Table and observe condition of
LEDs.
6. Disconnect output from the LEDs and note down the corresponding.
Observation Table:-
2 i/p NAND GATE:
SN74LS00N (NAND GATE)
TRUTH TABLE
A (I/P) B (I/P) Y(O/P )
0 0 1
0 1 1
1 0 1
1 1 0
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3 i/p NAND GATE:
NOT GATE:
SN74LS10N (THREE I/P NAND)
SN74LS04N (NOT GATE)
TRUTH TABLE
A Y
A B C Y (I/P) (O/P)
(I/P) (I/P) (I/P) (O/P )
0 1
0 0 0 1
1 0
0 0 1 1
0 1 0 1
2 i/p AND Gate:
0 1 1 1
1 0 0 1
SN74LS08N (AND GATE)
1 0 1 1
TRUTH TABLE
1 1 0 1
A B Y
1 1 1 0 (I/P) (I/P) (O/P)
0 0 0
0 1 0
1 0 0
1 1 1
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2 i/p OR Gate: 2 i/p NOR Gate:
SN74LS32N(OR GATE) SN74LS02N(NOR GATE)
TRUTH TABLE TRUTH TABLE
A (I/P) B (I/P) Y(O/P ) A B Y
(I/P) (I/P) (O/P )
0 0 0
0 0 1
0 1 1
0 1 0
1 0 1
1 0 0
1 1 1
1 1 0
2 i/p XOR Gate:
SN74LS86N(X-OR GATE)
TRUTH TABLE
A B Y
(I/P) (I/P) (O/P)
0 0 0
0 1 1
1 0 1
1 1 0
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Result:- We study and verified the Truth Tables of all gates.
Precautions:-
1. All Connections should be according to circuit diagram.
2. All Connections should be right and tight.
3. Reading should be taken carefully.
4. Power supply Switched Off after completing the Experiment.
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