Final Project in Digital Design

House Security System

Members:
Cherry May Abela
Sherwin Atender
Annabel Balane
Trazyl Joy Suplico
Rommel Terante

May 11, 2014 activity

Pin Configuration

Pin Configuration

 

Activity May 5 2014

           Logic Gates

"Schematic Diagram and Truth Table"

1.

2.

Lab Activity 1

Lab Activity 1

Logic Gates and Truth Tables

Logic Gates 

Truth Table

Logic Gates (Schematic Diagram, Truth Table, 74 series logic IC)

                             LOGIC GATES

 

Logic gates perform basic logical functions and are the fundamental building blocks of digital integrated circuits. Most logic gates take an input of two binary values, and output a single value of a 1 or 0. Some circuits may have only a few logic gates, while others, such as microprocessors, may have millions of them. There are seven different types of logic gates, which are outlined below.
In the following examples, each logic gate except the NOT gate has two inputs, A and B, which can either be 1 (True) or 0 (False). The resulting output is a single value of 1 if the result is true, or 0 if the result is false.

1. AND - True if A and B are both True
2. OR - True if either A or B are True
3. NOT - Inverts value: True if input is False; False if input is True
4. XOR - True if either A or B are True, but False if both are True
5. NAND - AND followed by NOT: False only if A and B are both True
6. NOR - OR followed by NOT: True only if A and B are both False
7. XNOR - XOR followed by NOT: True if A and B are both True or both False

By combining thousands or millions of logic gates, it is possible to perform highly complex operations. The maximum number of logic gates on an integrated circuit is determined by the size of the chip divided by the size of the logic gates. Since transistors make up most of the logic gates in computer processors, smaller transistors mean more complex and faster processors.

 

Logic gates

Digital systems are said to be constructed by using logic gates. These gates are the AND, OR, NOT, NAND, NOR, EXOR and EXNOR gates. The basic operations are described below with the aid of truth tables.

AND gate

The AND gate is an electronic circuit that gives a high output (1) only if all its inputs are high.  A dot (.) is used to show the AND operation i.e. A.B.  Bear in mind that this dot is sometimes omitted i.e. AB

 

OR gate

The OR gate is an electronic circuit that gives a high output (1) if one or more of its inputs are high.  A plus (+) is used to show the OR operation.

 

NOT gate

The NOT gate is an electronic circuit that produces an inverted version of the input at its output.  It is also known as an inverter.  If the input variable is A, the inverted output is known as NOT A.  This is also shown as A', or A with a bar over the top, as shown at the outputs. The diagrams below show two ways that the NAND logic gate can be configured to produce a NOT gate. It can also be done using NOR logic gates in the same way.

 

NAND gate

This is a NOT-AND gate which is equal to an AND gate followed by a NOT gate.  The outputs of all NAND gates are high if any of the inputs are low. The symbol is an AND gate with a small circle on the output. The small circle represents inversion.

 

NOR gate

This is a NOT-OR gate which is equal to an OR gate followed by a NOT gate.  The outputs of all NOR gates are low if any of the inputs are high.

The symbol is an OR gate with a small circle on the output. The small circle represents inversion.

 

 

EXOR gate

The 'Exclusive-OR' gate is a circuit which will give a high output if either, but not both, of its two inputs are high.  An encircled plus sign () is used to show the EOR operation.

EXNOR gate

The 'Exclusive-NOR' gate circuit does the opposite to the EOR gate. It will give a low output if either, but not both, of its two inputs are high. The symbol is an EXOR gate with a small circle on the output. The small circle represents inversion.

The NAND and NOR gates are called universal functions since with either one the AND and OR functions and NOT can be generated.
Note:
A function in sum of products form can be implemented using NAND gates by replacing all AND and OR gates by NAND gates.

A function in product of sums form can be implemented using NOR gates by replacing all AND and OR gates by NOR gates.

Table 1: Logic gate symbols

Table 2 is a summary truth table of the input/output combinations for the NOT gate together with all possible input/output combinations for the other gate functions. Also note that a truth table with 'n' inputs has 2ⁿ rows. You can compare the outputs of different gates.
Table 2: Logic gates representation using the Truth table

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Example

A NAND gate can be used as a NOT gate using either of the following wiring configurations.

                                        (You can check this out using a truth table.)

 

 

 

         A schematic, or schematic diagram, is a representation of the elements of a system using abstract, graphic symbols rather than realistic pictures. A schematic usually omits all details that are not relevant to the information the schematic is intended to convey, and may add unrealistic elements that aid comprehension. For example, a subway map intended for riders may represent a subway station with a dot; the dot doesn't resemble the actual station at all but gives the viewer information without unnecessary visual clutter. A schematic diagram of a chemical process uses symbols to represent the vessels, piping, valves, pumps, and other equipment of the system, emphasizing their interconnection paths and suppressing physical details. In an electronic circuit diagram, the layout of the symbols may not resemble the layout in the physical circuit. In the schematic diagram, the symbolic elements are arranged to be more easily interpreted by the viewer.

          A semi-schematic diagram combines some of the abstraction of a purely schematic diagram with other elements displayed as realistically as possible, for various reasons. It is a compromise between a purely abstract diagram (e.g. the schematic of the Washington Metro) and an exclusively realistic representation

 

 

 

                           Electrical Symbols & Electronic Symbols

Electrical symbols and electronic circuit symbols are used for drawing schematic diagram.
The symbols represent electrical and electronic components.

                               Table of Electrical Symbols

Symbol	Component name	Meaning
Wire Symbols
	Electrical Wire	Conductor of electrical current
	Connected Wires	Connected crossing
	Not Connected Wires	Wires are not connected
Switch Symbols and Relay Symbols
	SPST Toggle Switch	Disconnects current when open
	SPDT Toggle Switch	Selects between two connections
	Pushbutton Switch (N.O)	Momentary switch - normally open
	Pushbutton Switch (N.C)	Momentary switch - normally closed
	DIP Switch	DIP switch is used for onboard configuration
	SPST Relay	Relay open / close connection by an electromagnet
	SPDT Relay
	Jumper	Close connection by jumper insertion on pins.
	Solder Bridge	Solder to close connection
Ground Symbols
	Earth Ground	Used for zero potential reference and electrical shock protection.
	Chassis Ground	Connected to the chassis of the circuit
	Digital / Common Ground
Resistor Symbols
	Resistor (IEEE)	Resistor reduces the current flow.
	Resistor (IEC)
	Potentiometer (IEEE)	Adjustable resistor - has 3 terminals.
	Potentiometer (IEC)
	Variable Resistor / Rheostat (IEEE)	Adjustable resistor - has 2 terminals.
	Variable Resistor / Rheostat (IEC)
	Trimmer Resistor	Preset resistor
	Thermistor	Thermal resistor - change resistance when temperature changes
	Photoresistor / Light dependent resistor (LDR)	Photo-resistor - change resistance with light intensity change
Capacitor Symbols
	Capacitor	Capacitor is used to store electric charge. It acts as short circuit with AC and open circuit with DC.
	Capacitor
	Polarized Capacitor	Electrolytic capacitor
	Polarized Capacitor	Electrolytic capacitor
	Variable Capacitor	Adjustable capacitance
Inductor / Coil Symbols
	Inductor	Coil / solenoid that generates magnetic field
	Iron Core Inductor	Includes iron
	Variable Inductor
Power Supply Symbols
	Voltage Source	Generates constant voltage
	Current Source	Generates constant current.
	AC Voltage Source	AC voltage source
	Generator	Electrical voltage is generated by mechanical rotation of the generator
	Battery Cell	Generates constant voltage
	Battery	Generates constant voltage
	Controlled Voltage Source	Generates voltage as a function of voltage or current of other circuit element.
	Controlled Current Source	Generates current as a function of voltage or current of other circuit element.
Meter Symbols
	Voltmeter	Measures voltage. Has very high resistance. Connected in parallel.
	Ammeter	Measures electric current. Has near zero resistance. Connected serially.
	Ohmmeter	Measures resistance
	Wattmeter	Measures electric power
Lamp / Light Bulb Symbols
	Lamp / light bulb	Generates light when current flows through
	Lamp / light bulb
	Lamp / light bulb
Diode / LED Symbols
	Diode	Diode allows current flow in one direction only (left to right).
	Zener Diode	Allows current flow in one direction, but also can flow in the reverse direction when above breakdown voltage
	Schottky Diode	Schottky diode is a diode with low voltage drop
	Varactor / Varicap Diode	Variable capacitance diode
	Tunnel Diode
	Light Emitting Diode (LED)	LED emits light when current flows through
	Photodiode	Photodiode allows current flow when exposed to light
Transistor Symbols
	NPN Bipolar Transistor	Allows current flow when high potential at base (middle)
	PNP Bipolar Transistor	Allows current flow when low potential at base (middle)
	Darlington Transistor	Made from 2 bipolar transistors. Has total gain of the product of each gain.
	JFET-N Transistor	N-channel field effect transistor
	JFET-P Transistor	P-channel field effect transistor
	NMOS Transistor	N-channel MOSFET transistor
	PMOS Transistor	P-channel MOSFET transistor
Misc. Symbols
	Motor	Electric motor
	Transformer	Change AC voltage from high to low or low to high.
	Electric bell	Rings when activated
	Buzzer	Produce buzzing sound
	Fuse	The fuse disconnects when current above threshold. Used to protect circuit from high currents.
	Fuse
	Bus	Contains several wires. Usually for data / address.
	Bus
	Bus
	Optocoupler / Opto-isolator	Optocoupler isolates connection to other board
	Loudspeaker	Converts electrical signal to sound waves
	Microphone	Converts sound waves to electrical signal
	Operational Amplifier	Amplify input signal
	Schmitt Trigger	Operates with hysteresis to reduce noise.
	Analog-to-digital converter (ADC)	Converts analog signal to digital numbers
	Digital-to-Analog converter (DAC)	Converts digital numbers to analog signal
	Crystal Oscillator	Used to generate precise frequency clock signal
Antenna Symbols
	Antenna / aerial	Transmits & receives radio waves
	Antenna / aerial
	Dipole Antenna	Two wires simple antenna
Logic Gates Symbols
	NOT Gate (Inverter)	Outputs 1 when input is 0
	AND Gate	Outputs 1 when both inputs are 1.
	NAND Gate	Outputs 0 when both inputs are 1. (NOT + AND)
	OR Gate	Outputs 1 when any input is 1.
	NOR Gate	Outputs 0 when any input is 1. (NOT + OR)
	XOR Gate	Outputs 1 when inputs are different. (Exclusive OR)
	D Flip-Flop	Stores one bit of data
	Multiplexer / Mux 2 to 1	Connects the output to  selected input line.
	Multiplexer / Mux 4 to 1
	Demultiplexer / Demux 1 to 4	Connects selected output to the input line.

Truth Tables

A truth table shows how a logic circuit's output responds to various combinations of the inputs, using logic 1 for true and logic 0 for false. All permutations of the inputs are listed on the left, and the output of the circuit is listed on the right. The desired output can be achieved by a combination of logic gates. A truth table for two inputs is shown, but it can be extended to any number of inputs. The input columns are usually constructed in the order of binary counting with a number of bits equal to the number of inputs.

Truth tables help understand the behaviour of logic gates.

• They show how the input(s) of a logic gate relate to its output(s).
• The gate input(s) are shown in the left column(s) of the table with all the different possible input combinations. This is normally done by making the inputs count up in binary.
• The gate output(s) are shown in the right hand side column.

74 series logic IC datasheets!

part #	description
74LS00	Quad 2-Input NAND Gate
74LS01	Quad 2-Input NAND Gate; Open Collector Outputs
74LS02	Quad 2-Input NOR Gate
74LS03	Quad 2-Input NAND Gate; Open Collector Outputs
74LS04	Hex Inverter
74LS05	Hex Inverter; Open Collector Outputs
74LS06	Hex Inverter; Open Collector High Voltage Outputs
74LS07	Hex Buffer; Open Collector High Voltage Outputs
74LS08	Quad 2-Input AND Gate
74LS09	Quad 2-Input AND Gate; Open Collector Outputs
74LS10	Triple 3-Input NAND Gate
74LS11	Triple 3-Input AND Gate
74LS12	Triple 3-Input NAND Gate; Open Collector Outputs
74LS13	Dual 4-Input NAND Schmitt Triggers
74LS14	Hex Schmitt-Trigger Inverter
74LS15	Triple 3-Input AND Gate; Open Collector Outputs
74LS16	Hex Inverter; Open Collector 15V Outputs
74LS17	Hex Driver; Open Collector 15V Outputs
74LS19	NAND Schmitt Trigger; Totem Pole Output
74LS20	Dual 4-Input NAND Gate
74LS21	Dual 4-Input AND Gate; Open Collector Outputs
74LS22	Dual 4-Input NAND Gate; Open Collector Outputs
74LS23	2x Four input NOR with Strobe
74LS25	2x Four input NOR with Strobe
74LS26	Quad 2-Input NAND Gate; OC (15V)
74LS27	Triple 3-Input NOR Gate
74LS28	Quad 2-Input NOR Gates
74LS30	8-Input NAND Gate
74LS31	Delay Element
74LS32	Quad 2-Input OR Gate
74LS33	Quad 2-Input NOR Gate; Open Collector Outputs
74LS37	Quad 2-Input NAND Gates
74LS38	Quad 2-Input NAND Gates; Open Collector Outputs
74LS39	4x Two input NAND, Open collector
74LS40	Dual 4-Input NAND Gates
74LS42	BCD to DECIMAL Decoder
74LS45	Four-to-Ten (BCD to Decimal) DECODER, High current
74LS46	BCD to Seven-Segment DECODER, Open Collector, lamp test and leading zero handling
74LS47	BCD to 7-Segment Decoder; Open Collector Outputs (15V)
74LS48	BCD to 7-Seg Decoder; Outputs Active high
74LS49	BCD to 7-Seg Decoder-Outputs Active High
74LS50	2x (Two input AND) NOR (Two input AND), expandable
74LS51	Dual AND-OR-INVERT Gates
74LS53	NOR of Four Two input ANDs, expandable
74LS54	4-Wide AND-OR-INVERT Gate
74LS55	4-Wide; 2-Input AND-OR-INVERT Gate
74LS56	Frequency Divider
74LS57	Frequency Divider
74LS64	4-3-2-2 AND-OR-INVERT
74LS65	4-3-2-2 AND-OR-INVERT
74LS68	Dual 4-Bit Decade or Binary Counter
74LS69	Dual 4-Bit Decade or Binary Counter
74LS70	1x gated JK FLIPFLOP with preset and clear
74LS72	1x gated JK FLIPFLOP with preset and clear
74LS73	Dual J-K Flip-Flop
74LS74	Dual D-Type Flip-Flop
74LS75	Dual 2-Bit D-Type Flip-Flop
74LS76	Dual J-K Flip-Flop
74LS77	4-Bit D-Type Latch
74LS78	Dual J-K Flip-Flop
74LS83	4-Bit Full Adder
74LS85	4-Bit Comparator
74LS86	Quad Exclusive OR Gate
74LS90	Decade Counter
74LS91	8-Bit Shift Register
74LS92	Divide-By-12 Counter
74LS93	4-Bit Binary Counter
74LS94	Four bit SHIFT register
74LS95	4-Bit Shift Register with Parallel Inputs and Outputs
74LS96	5-Bit Shift Register with Parallel Inputs and Outputs
74LS107	Dual J-K Master Slave Flip-Flop
74LS109	Dual J-K Flip-Flop
74LS112	Dual J-K Flip-Flop with Preset and Clear
74LS113	Dual J-K Flip-Flop
74LS114	Dual J-K Flip-Flop
74LS116	2x Four bit LATCH with clear
74LS121	Monostable Multivibrator
74LS122	Retriggerable Monostable Multivibrator
74LS123	Retriggerable Monostable Multivibrator
74LS124	2x Clock Generator or Voltage Controlled Oscillator
74LS125	Quad Line Driver; 3-State Outputs
74LS126	Quad Line Driver; 3-State Outputs
74LS128	4x Two input NOR, Line driver
74LS130	Retriggerable Monostable Multivibrator
74LS132	Quad 2-Input NAND Schmitt Trigger
74LS133	13-Input NAND Gate
74LS134	Twelve input NAND, Tri-state
74LS135	4x Two input XOR (exclusive or)
74LS136	Quad 2-Input Exclusive OR Gates
74LS137	3-Line to 8-Line Demultiplexer with Address Latch
74LS138	3-Line to 8-Line Demultiplexer
74LS139	2-Line to 4-Line Decoder/Demultiplexer
74LS140	2x Four input NAND, 50 ohm Line Driver
74LS143	Four bit counter and latch with 7-segment LED driver
74LS145	BCD to Decimal Decoder/Driver
74LS147	10-Line to 4-Line Priority Encoder
74LS148	8-Line to 3-Line Priority Encoder
74LS150	16-1 SELECTOR (multiplexer)
74LS151	8-Line to 1-Line Multiplexer
74LS153	Dual 4-Line to 1-Line Multiplexer
74LS154	4-Bit Binary Decoder/Demultiplexer
74LS155	Dual 2-Bit Binary Decoders/Demultiplexer
74LS156	Dual 2-Bit Binary Decoders/Demultiplexer
74LS157	Quad 2-Line to 1-Line Multiplexer
74LS158	Quad 2-Line to 1-Line Multiplexer
74LS159	4-16 DECODER (demultiplexer), Open collector
74LS160	4-Bit Synchronous Programmable Counter
74LS161	4-Bit Synchronous Programmable Counter
74LS162	4-Bit Synchronous Programmable Counter
74LS163	4-Bit Synchronous Programmable Counter
74LS164	8-Bit Shift Register with Parallel Outputs
74LS165	8-Bit Shift Register with Parallel Inputs
74LS166	8-Bit Shift Register with Parallel Inputs
74LS168	Up/Down 4-Bit Synchronous Counter
74LS169	Up/Down 4-Bit Synchronous Counter
74LS170	16-Bit RAM; Open Collector Outputs
74LS173	4-Bit Quad D-Type Flip-Flops; 3-State Outputs
74LS174	Hex D-Type Flip-Flop
74LS175	Quad D-Type Flip-Flop
74LS180	Four bit parity checker
74LS181	4-bit Arithmetic Logic Unit
74LS182	Look Ahead Carry Generator
74LS183	Dual Carry-Save Full Adder
74LS190	Synchronous Up/Down Decade Counter
74LS191	Synchronous Up/Down 4-Bit Binary Counter
74LS192	Synchronous Up/Down Decade Counter
74LS193	Synchronous Up/Down 4-Bit Binary Counter
74LS194	4-Bit Bidirectional Shift Register
74LS195	4-Bit Parallel-Access Shift Register
74LS196	Programmable Decade Counter
74LS197	Programmable Decade Counter
74LS198	Eight bit parallel in and out bidirectional SHIFT register
74LS199	Eight bit parallel in and out bidirectional SHIFT register, JK serial input
74LS221	Dual Monostable Multivibrator; Schmitt-Trigger Input
74LS240	Octal Inverting Buffer/Transciever; 3-State Outputs
74LS241	Octal Buffer/Transciever; 3-State Outputs
74LS242	Quad 3-State Bus Transceiver
74LS243	4-Bit Bidirectional Bus Driver
74LS244	Octal 3-State Noninverting Buffer
74LS245	Octal 3-State Noninverting Bus Transceiver
74LS247	BCD to 7-Seg Decoder/Display Driver OC (15V)
74LS248	BCD to 7-Seg Decoder/Display Driver OC (15V)
74LS249	BCD to 7-Seg Decoder/Display Driver OC (15V)
74LS251	8-Line to 1-Line Multiplexer; 3-State Outputs
74LS253	Dual 4-Input Data Selecttor/Multiplexer 3-State
74LS256	Dual 4-Bit Addressable Latch
74LS257	Quad 2-Line to 1-Line Multiplexers; 3-State Outputs
74LS258	Quad 2-Line to 1-Line Multiplexers; 3-State Outputs
74LS259	8-Bit Adressable Latch
74LS260	Dual 5-Input NOR Gate
74LS266	Quad Exclusive NOR Gate
74LS269	8-BIT BIDIRECTIONAL BINARY COUNTER
74LS273	Octal D-Type Flip-Flop; Common Clock and Clear
74LS279	Quad SR-Flip-Flops
74LS280	9-Bit Parity checker
74LS283	4-Bit Full Adder
74LS290	4-Bit Decade/Binary Counter
74LS298	Quad 2-Line to 1-Line Multiplexers with Latch
74LS299	8-Bit Bidirectional Universal Shift Register
74LS322	8-Bit Sign-Extend Shift Register
74LS323	8-Bit Universal Shift Register with Latch
74LS348	8-Line to 3-Line Priority Encoder with 3-State Outputs
74LS352	Dual 4-Line to 1-Line Multiplexers
74LS353	Dual 4-Line to 1-Line Multiplexers with 3-State Outputs
74LS365	Hex Bus Line Drivers
74LS366	3-State Hex Line Driver
74LS367	Hex Bus Line Drivers
74LS368	Hex Inverting Bus Line Drivers
74LS373	Octal D-Type Latch
74LS374	Octal D-Type Flip-Flop
74LS375	Quad D-Type Latch
74LS377	Octal D-Type Flip-Flop
74LS378	Hex D-Type Flip-Flop
74LS379	Quad D-Type Flip-Flop
74LS386	Quad 2-Input Exclusive OR Gates
74LS390	Dual Decade Counters
74LS393	Dual Decade Counters
74LS395	4-Bit Shift Register with 3-State Outputs
74LS398	Quad 2-Input Register
74LS399	Quad 2-Input Register
74LS490	Dual Decade Counter
74LS521	8-BIT IDENTITY COMPARATOR
74LS533	Octal D-Type Transparent Latche
74LS534	Octal Invering D-Type Flip-Flop
74LS538	1-OF-8 DECODER WITH 3-STATE OUTPUTS
74LS540	8-Bit Inverting Line Driver
74LS541	OCTAL BUFFER/LINE DRIVER WITH 3-STATE OUTPUTS
74LS543	OCTAL REGISTERED TRANSCEIVER, NON-INVERTING, 3-STATE
74LS544	OCTAL REGISTERED TRANSCEIVER, INVERTING, 3-STATE
74LS568	4-BIT BIDIRECTIONAL COUNTERS (WITH 3-STATE OUTPUTS)
74LS569	4-Bit Synchronous Counter
74LS574	8-Bit D-Type Flip-Flop/Bus Driver
74LS579	8-BIT BIDIRECTIONAL BINARY COUNTER (3-STATE)
74LS620	OCTAL BUS TRANSCEIVER WITH 3-STATE OUTPUTS (INVERTING AND NONINVERTING)
74LS623	Octal Bus Transcievers
74LS629	Voltage Controlled Oscilator
74LS640	Octal Bus Transciever
74LS646	Octal Bus Transciever
74LS648	Octal Bus Transciever/Register
74LS657	OCTAL BIDIRECTIONAL TRANSCEIVER WITH 8-BIT PARITY GENERATOR CHECKER (3-STATE OUTPUTS)
74LS669	4-Bit Synchronous Up/Down Counter
74LS670	4-By-4 Register File; 3-State Outputs
74LS682	8-Bit Magnitude/Identity Comparator
74LS684	8-Bit Magnitude Comparators
74LS688	8-Bit Magnitude Comparators
74LS748	8-Line to 3-Line Priority Encoder
74LS779	8-BIT BIDIRECTIONAL BINARY COUNTER (3-STATE)
74LS795	Octal Buffer with 3-State Outputs
74LS848	8-Line to 3-Line Priority Encoder with 3-State Outputs
74LS2245	25Ohm Octal Bidirectional Transceiver With 3-State Inputs and Outputs
74LS3893	QUAD FUTUREBUS BACKPLANE TRANSCEIVER (3 STATE + OPEN COLLECTOR)