Logic 74xxxx Series Datasheets

74LS00 Quad 2 input NAND gate

74LS01 Quad 2 input NAND gate (OC)

74LS02 Quad 2 input NOR gate

74LS03 Quad 2 input NAND gate

74LS04 Hex Inverter

74LS05 Hex Inverter (OC)

74LS06 Hex Inverter buffer/driver

74LS08 Quad 2 input AND

74LS09 Quad 2 input AND gate (OC)

74LS10 Triple 3 input NAND gate

74LS11 Triple 3 input AND gate

74LS12 Triple 3 input NAND gate (OC)

74LS13 Dual 4-input NAND gate Schmitt trigger

74LS14 Hex Inverter Schmitt trigger

74LS16 Hex Inverter (OC)

74LS15 Triple 3 input AND gate (OC)

74LS20 Dual 4 input NAND gate

74LS21 Dual 4 input AND gate

74LS22 Dual 4 input NAND gate (OC)

7425 Dual 4 input NOR gate with strobe

74LS22 Dual 4 input NAND gate (OC)

7425 Dual 4 input NOR gate with strobe

74LS27 Triple 3 input NOR gate

74LS30 8 input NAND gate

74LS32 Quad 2 input OR gate

74LS38 Quad 2 input NAND gate Buffer

74LS42 BCD to DEC decoder

7445 BCD to DEC decoder

74LS47 BCD to 7 seg decoder/driver

74LS48 BCD to 7 seg decoder/driver

74LS51 AND/OR/INVERT gate

74LS54 AND/OR/INVERT gate

74F64 AND/OR/INVERT gate

7470 JK flip flop

7472 JK M/S flip flop

74LS73 Dual JK flip flop with clear

74LS74 Dual D-Type flip-flops with preset and clear

74LS75 4 bit bistable latch

74LS76 Dual JK flip-flops with preset and clear

74LS83 4 bit full adder

74LS85 4 bit magnitude comparator

74LS86 Quad 2 input XOR gate

74LS90 Decade counter

74LS91 8-bit shift register

74LS92 Divide by 12 counter

74LS93 Binary counter

74LS95 4 bit shift register

74LS107 Dual JK flip-flops with clear

74LS109 Dual JK pos edge trig flip flop

74LS112 Dual JK neg edge trig flip flop

74121 Monostable multivibrator

74LS122 Monostable multivibrator

74LS123 Monostable multivibrator

74LS125 Monostable multivibrator

74LS132 Quad 2 input NAND gate Schmitt trigger

74S133 13 input NAND

74LS136 Quad 2 input XOR (O.C)

74LS138 3-to-8 line decoder/demux

74LS139 Dual 1-of-4 decoder/demux

74LS147 10 line - 4 line octal priority encoder

74LS148 8 line - 3 line octal priority encoder

74150 Data selector/mux

74LS151 8 input MUX

74LS153 Dual 4-to-1 Multiplexer

74LS154 4-to16 decoder/demux

74LS155 Dual 2 line to 4 line decoder / demux

74LS156 Dual 2 line to 4 line decoder / demux (O.C)

74LS157 Quad 2 input MUX

74LS158 Quad 2 input MUX with invereted outputs

74LS160 BCD decade counter

74LS161 Synchronous 4 bit binary counter

74LS162 BCD decade counter counter

74LS163 Asynchronous 4 bit binary counter

74LS164 8 bit SIPO shift register

74LS165 8 bit PISO shift register

74LS166 8 bit PISO shift register

74LS174 Hex D type flip flop with clear

74LS175 Quad D type flip flop with clear

74176 Decade Counter

74177 Binary Counter

74LS191 4 bit binary up / down counter

74LS192 BCD up / down counter

74LS193 4 bit binary up / down counter

74LS195 4 bit shift register

74LS196 Presettable decade counter

74LS197 Presettable binary counter

74199 8-bit shift register

74LS221 Dual monostable multivibrator

74S225 16x5 FIFO memory

74LS240 Octal buffer/line driver

74LS241 Octal 3-state buffer

74LS244 Octal buffer/line driver

74LS245 Octal bus transceiver

74LS251 Data selector / MUX

74LS257 Quad 2 input mux 3-state

74LS259 8 bit addressable latch

74LS266 Quad 2 input XNOR (O.C)

74LS273 Octal D type flip flop with clear

74LS280 9 bit odd / even parity generator

74LS298 Quad 2 input MUX with storage

74LS299 8 bit universal shift register

74LS323 8-Bit Shift register

74LS367 Hex bus driver

74LS368 Hex bus driver with inverters

74LS373 Octal transparent latch

74LS374 Octal D type flip flop 3-state

74LS390 Dual 4 bit decade counter

74LS393 Dual 4 bit binary counter

74LS395 4 bit shift register

74LS540 Octal buffer 3-state

74LS541 Octal buffer 3-state outputs

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What is Electric Current

An electric current is a flow of microscopic particles called ELECTRONS flowing through wires and electronic components. It can be likened to the flow of water through pipes and radiators etc.
As water is pushed through pipes by a pump, electric current is pushed through wires by a battery. Hot water does work by heating radiators. Electric current does work by heating fires, lighting lamps, ringing bells, electroplating etc.

A basic law of the universe is that like charges repel and unlike attract. Two negatives will repel each other. A negative and a positive will attract each other. An electron has a negative charge.
The negative (-ve) terminal of a battery will push negative electrons along a wire.
The positive (+ve) terminal of a battery will attract negative electrons along a wire.

Electric current will therefore flow from the -ve terminal of a battery, through the lamp, to the positive terminal.

This is called electron current flow.

The current flows round the circuit.

In some books current is said to flow from +ve to -ve. This was guessed at before the electron was discovered. They guessed wrong! This is called conventional current flow.

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Potential Dividers

Make sure that you understand Ohms Law before reading this.

The total resistance of the two series resistors is 8 ohms + 4 ohms = 12 ohms.
The current flowing around the circuit is 12 volts/12 ohms = 1 amp (Ohms Law).
The voltage across the 8 ohm is 1 amp x 8 ohms = 8 volts (again Ohms Law).
The voltage across the 4 ohm is 1 amp x 4 ohms = 4 volts (Mr Ohm again).
The 12 volts of the battery has been divided into 8 volts and 4 volts.

By selecting values for the two resistors, the 12 volts can be divided into any two voltages which add up to 12 volts. For example, 3 volts and 9 volts, 6 volts and 6 volts etc.

A circuit requiring less than 12 volts can be connected across the lower resistor, as long as it requires a current much lower than the current through the two resistors.

If a cardboard strip, coated with carbon, is connected across the battery, together with a "wiper" which can be moved up or down the strip, then you have a POTENTIOMETER (POT for short.) With the wiper at the top then the output is 12 volts. With the wiper at the bottom then the output is zero volts. Any output between 12 volts and zero can be obtained by positioning the wiper correctly.

In practice, the strip is curved and the wiper is joined to a spindle which rotates the wiper on the strip when a control knob is twisted. In the drawings, the wiper is the centre connection. Most front panel controls such volume and brightness are "pots". Their purpose is to adjust the voltage fed from one stage to the next.

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Schmitt Trigger

In the top diagram, the input voltage increases from zero, along the bottom horizontal line.
The output voltage remains at zero on the vertical line.
However, when the input voltage reaches 1.7 volts, the output shoots up from zero to 5 volts.
Reducing the input voltage, as shown in the top horizontal line does not cause the output to drop to zero immediately.
This only happens when the input voltage is reduced to 0.9 volts.
The input level at which the output increases to maximum, and the level at which it drops to zero are different.

This is called HYSTERESIS.

In the lower diagram Schmitt Trigger action is demonstrated in another manner.
The black graph represents a noisy logic signal received from the moon.
This is the input to the Schmitt Trigger.
The green graph is the output signal.
The output remains at zero until the input exceeds 1.7 volts.
The output then shoots up to 5 volts and remains at 5 volts until the input drops to 0.9 volts.
The output then drops to zero.
An almost perfect output is recovered from a very noisy input.

With no signal in,Tr1 has no forward bias and is cut off.
The collector voltage of Tr1 is high, turning Tr2 on.
The emitter current of Tr2 flowing through R2 produces 1 volt across R2.
Since the base of Tr1 is at zero volts, the base/emitter junction of Tr1 is reverse biased by 1 volt.
The input signal has to exceed this voltage plus 0.6 volts (1+0.6 = 1.6 volts) to forward bias Tr1.

INPUT GOES HIGH TO MAKE OUTPUT HIGH

The input signal increases from zero.
Once the input voltage exceeds 1.6 volts,Tr1 begins to conduct.
Its collector voltage starts to fall and the base voltage of Tr2 falls.
The emitter current of Tr2 through falls, reducing the voltage across it.
This further increases the conduction of Tr1, producing a cumulative effect.
Tr1 comes on very rapidly and Tr2 goes off.
Tr2 collector voltage goes high.

INPUT GOES LOW TO MAKE OUTPUT LOW

When the input voltage falls, it has to go below 0.6 volts before Tr1 collector current starts to fall.
Again there is a cumulative action which rapidly turns Tr1 off and Tr2 on.
Tr2 collector voltage falls.
The difference in the values of Tr1 base TURN ON and TURN OFF voltages is known as HYSTERESIS.
The Schmitt Trigger can be used to clean up noisy signals or to speed up slow rise and fall times of pulses.

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ASCII Table

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MATERIAL POKOK DAN KOMPONEN DASAR KELISTRIKAN

ELECTRIC INSULATOR
adalah material|bahan yg memiliki sifat dpt menyekat listrik. Ukuran resistansi|hambatan listriknya maksimum dan konduktansi|hantaran listriknya minimum. Misalnya, kayu, kaca, melamin, keramik, karet, plastik, dlsb. Insulator yg umum digunakan pd kendaraan bermotor adalah plastik, karet, dan keramik. Material insulator digunakan utk membuat pita penyekat (insulator tape), pembungkus kawat (wire jacket), pegangan saklar (switch handle), dlsb. N/B: di Indonesia sering disebut sbg ISOLATOR atau pita ISOLASI.

DIELEKTRIK
adalah material insulator|penyekat listrik yg memiliki kemampuan sangat baik menahan tegangan listrik pd jarak sangat dekat, shg menahan medan listrik diantaranya. Dielektrik bisa padat, cair, atau gas. Dielektrik ideal atau sempurna adalah yg dpt menahan medan listrik tanpa sedikitpun ada energi hilang diantaranya. Dielektrik riel adalah tak sempurna, dan menimbulkan kehilangan "histerysis", suatu penundaan dlm perubahan suatu efek dpt diamati dlm tanggapan thdp suatu perubahan dlm mekanisme yg menghasilkan efek tsb. Lbh jauh ttg histerisis ini tak dibahas disini.

DIELECTRIC INTENSITY
adalah ukuran kekuatan maksimum material dielektrik utk menahan tegangan | beda potensial listrik dan kekuatan medan listrik antara dua sisi permukaannya tanpa hancur pd kondisi tertentu, diukur dlm Volt per meter [per cm, atau per mm].

ELECTRIC RESISTOR
adalah material|bahan yg memiliki sifat dpt menghambat listrik. Ukuran resistansi|hambatan listriknya mendekati maksimum dan konduktansi|hantaran listriknya mendekati minimum. Misalnya, karbon|arang, dlsb. Resistor listrik sekaligus juga adalah resistor panas.

ELECTRIC CONDUCTOR
adalah material|bahan yg memiliki sifat dpt menghantar listrik. Ukuran konduktansi|hantaran listriknya mendekati maksimum dan resistansi|hambatan listriknya mendekati minimum. Misalnya, metal|logam, spt tembaga dan perak, dlsb. Konduktor listrik sekaligus juga adalah konduktor panas. Material konduktor digunakan utk membuat kabel|kawat listrik (electric wrire), perisai panas (heat sink), dlsb.

ELECTRIC SEMICONDUCTOR
adalah material|bahan yg memiliki dua-sifat, dimana pd rangkum kondisi tertentu ia berlaku sbg konduktor, dan pd rangkum kondisi tertentu lain ia berlaku sbg resistor atau bahkan insulator. Material ini memiliki koefisien suhu resistansi negativ (negative temperature coeficient of resistance), dimana resistansi|hambatan listriknya merosot dan konduktansi|hantaran listriknya meningkat selaras dgn kenaikan suhu|temperatur dan ketakmurnian kisi kristal materialnya, dan sebaliknya. Misalnya, silikon, germanium, gallium arsenik, dlsb. Material semikonduktor digunakan utk membuat komponen elektronik terpisah (discrete) spt dioda [mencakup LED (light emitting diode)] dan transitor, dan komponen elektronik terpadu (integrated), rangkaian terpadu (intgrated circuit, IC) spt gerbang logika (logic gate). Penerapannya antara lain adalah sebagai saklar elektronik (electronic switch), pd rangkaian saklar angkani (digital switching circuit), pengedip elektronik (electronic flasher), dlsb.

ELECTRIC SUPERCONDUCTOR
adalah material|bahan yg dpt memiliki efek superkonduktivitas, yakni konduktansi maksimum dan resistansi minimum [mendekati nol] pd rangkum suhu|temperature tertentu. Material semacam ini, bila temperaturnya diturunkan dibawah temperatur transisi, mendekati O derajat mutlak, apalagi dibawah 0, maka resistansi listriknya pun merosot mendekati 0 Ohm.

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Conductors and Insulators

CONDUCTORS

* These are materials in which it is easy to get electrons to move and provide a flow of electric current.
* Conductors are mostly metals such as gold, silver, copper, iron and lead.
* Carbon is a conductor as well as some gases (as in fluorescent tubes) and water containing some chemicals.
* These are not perfect conductors and offer some resistance to the flow of current.

The resistance of a conductor (such as a metal rod) is determined by three things.

(1) its length. The longer its length the higher its resistance.
(2) its cross-sectional area. The bigger this is the lower is its resistance.
(3) the material of which it is made.

All materials have RESISTIVITY. The higher the value of resistivity the higher the resistance.
It is measured in OHM METERS.

Resistance = (length x resistivity) / cross-sectional area


INSULATORS

* These are materials in which it is difficult to get current to flow. Examples are rubber, pvc, paper, polystyrene and oil.Even with these it is possible to get some current flowing if the applied voltage is high enough.
* There is another class of materials called semi-conductors.
These have a resistance between insulators and conductors.
Examples are silicon and germanium and are used in diodes and transistors.

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The Cathode Ray Tube

Cathode Ray Tube

The Cathode Ray Tube (CRT) is used in oscilloscopes, radar, monitors and television receivers.

It consists of a glass envelope made from a neck and cone.
All air has been extracted so that it contains a vacuum.

At the narrow end are pins which make connection with an internal ELECTRON GUN.
Voltages are applied to this gun to produce a beam of electrons.
This electron beam is projected towards the inside face of the screen.

The face is coated with a PHOSPHOR which PHOSPHORESCES (glows) when hit by the beam.
This produces a spot of light on the centre of the face of the CRT.
By varying the beam current, spot BRIGHTNESS can be controlled.
Controlling the diameter of the beam controls FOCUS.

Phosphors come in a range of colours.

On its way from the gun to the screen the beam passes between 2 sets of plates.
They are called the X and Y plates (as in graphs).
By applying voltages to these plates the beam can be deflected.
This causes the spot to move from the centre of the screen to another position on the screen.
The X plates plates deflect the spot horizontally, the Y plates vertically.
Thus the spot can be deflected to any position on the screen.
External deflection coils are often used instead of the internal deflection plates.

Note that dropping a CRT causes it to IMPLODE which is as dangerous as an explosion.

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What is phase

The generator at the power station which produces our AC mains rotates through 360 degrees to produce one cycle of the sine wave form which makes up the supply.

In the next diagram there are two sine waves.

They are out of phase because they do not start from zero at the same time.

To be in phase they must start at the same time.

The waveform A starts before B and is LEADING by 90 degrees.

Waveform B is LAGGING A by 90 degrees.

The last diagram, known as a PHASOR DIAGRAM, shows this in another way.

The phasors are rotating anticlockwise as indicated by the arrowed circle.
A is leading B by 90 degrees.

The length of the phasors is determined by the amplitude of the voltages A and B.

Since the voltages are of the same value then their phasors are of the same length.

If voltage A was half the voltage of B then its phasor would be half the length of B.

All this has nothing to do with "set your phasors on stun".

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Resistors Colour Code

Ignore the colour of the resistor body.

Most resistors have three coloured bands close together at one end and one single band at the other.

The three adjacent band give the resistor value.

The band nearest the wire lead gives the value of the first digit. e.g Brown = 1.

The next band gives the value of the next digit e.g. red = 2

The third band gives the number of zeros which follows the two digits.e.g. orange = 3 zeros = 000.

Therefore a resistor with brown, red, orange bands would have a value of 12000 ohms.

This resistor has a value of 2,700,000 ohms.

A green blue black resistor would be 56 ohms. (black indicates that there are no zeros).

Black = 0
Brown = 1
Red = 2
Orange = 3
Yellow = 4
Green = 5
Blue = 6
Violet = 7
Grey = 8
White = 9

If the third band is silver then divide the value of the first two digits by 100, if gold divide by 10.
e.g. red violet gold is 2.7 ohms.

The fourth band indicates the tolerance.
e.g. brown indicates plus or minus 1%.
a 100 ohm 1% resistor can be in value between 99 ohms and 101 ohms.

brown 1%
red 2%
gold 5%
silver 10%
none 20%

If there is a fifth pink band this indicates a high stability resistor.

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Ohm's Law

Ohm's Law
The voltmeter is connected across the resistor, to measure the voltage across the resistor. The ammeter is connected in series with the resistor, to measure the current flowing around the circuit and through the resistor.

Mr Ohm discovered that if you double the voltage across the resistor then the current through it doubles. If you halve the voltage then the current is halved. This means that the current is PROPORTIONAL to the voltage.

He also found that if you double the value of the resistor then the current through it is halved. If the value of the resistor is halved the the current is doubled. Thus the current is INVERSELY PROPORTIONAL to the resistance.

To use the VIR triangle place your finger over the value you wish to find. If you wish to find V then multiply I by R. If you wish to find I then divide V by R.

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Watts and Joules

When current passes through a resistor, electrical energy is converted into heat.
This heat is DISSIPATED into the surrounding air.
The rate at which this dissipation occurs is called POWER and is measured in WATTS.
The amount of power can be calculated by using one of three methods.

(1) Power = V x I watts
(2) Power = (V x V)/R watts
(3) power = (I x I)R watts
Also see the page with the VIRP wheel.

If we place a 10 ohm resistor across a 20 volt battery then Ohms law says that I = V/R = 20/2 =2 amps will flow.

Using (1)
power = 20 x 2 = 40 watts

Using (2)
power = (20 x 20)/10 = 400/10 = 40 watts.

using (3)
power = (2 x 2)x10 = 4 x 10 = 40 watts.

Using three different formulae we still arrive at the same answer.

We know that power is the rate at which energy is used.
The amount of energy used is measured in JOULES.

Joules = watts x seconds, therefore watts = joules/seconds.

A 1000 watt fire will dissipate 1000 joules per second.
With resistors, the greater the dissipation the hotter it gets, and the larger the resistor needs to be.

The electric meter in your house measures UNITS of electricity.
A unit is when you use 1000 watts for one hour. This is called 1 Kilowatt hour.

It is kilowatts x hours. A 100 watt (0.1 kilowatts) lamp left on for 24 hours uses 0.1 x 24 = 2.4 units.

You or your parents are charged by the unit.
If a unit cost 5 pence then the lamp would cost 12 pence a day to run.
Switch it off and help to save the world.

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Sejarah Penemuan Integrated Circuit (IC)

Pada tahun 1958, seorang insinyur bernama Jack Kilby yang bekerja pada Texas Intruments mencoba memecahkan masalah dengan memikirkan sebuah konsep menggabungkan seluruh komponen elektronika dalam satu blok yang dibuat dari bahan semikonduktor. Terciptalah chip yang pertama, meskipun masih dengan segala kekurangan dan kelemahannya. Beberapa saat setelah itu, Robert Noyce, yang bekerja pada Fairchild Semiconductor Corporation, menemukan hal serupa, meskipun mereka bekerja pada dua tempat yang berbeda.

Sejak penemuan pertama sebuah IC, riset banyak dilakukan untuk menyempurnakan sebuah IC. Beberapa hal yang cukup penting dalam sebuah IC adalah ukuran dan daya listrik yang dibutuhkan sebuah IC untuk berfungsi dengan baik. Saat ini, sebuah IC yang ukurannya sekitar jari kuku manusia, di dalamnya terdapat ratusan juta komponen yang terintegrasi menjadi satu.

Gorden Moore, co-founder perusahaan Intel, pada tahun 1965 memperkirakan bahwa jumlah transistor yang terdapat dalam sebuah IC akan bertambah 2 kali setiap 18 bulan sekali. Kecenderungan peningkatan jumlah transistor ini telah terbukti setelah sekian lama dan diperkirakan akan terus berlanjut.

Sebagai contoh perkembangan IC, sebuah 64-Mbit DRAM yang pertama kali di pasaran pada tahun 1994, terdiri dari 3 juta transistor. Dan microprocessor Intel Pentium 4 terdiri lebih dari 42 juta transistor dan kira-kira terdapat 281 IC didalamnya. Bahkan berdasar pada International Technology Roadmap for Semiconductor (ITRS), diharapkan akan tersedia sebuah chip yang terdiri dari 3 milyar transistor pada tahun 2008.

Umumnya, bahan semikonduktor yang digunakan dalam pembuatan IC, adalah silikon. Beberapa bahan lain pun juga memungkinkan untuk digunakan. Proses pembuatan IC sendiri terdiri dari ratusan step. Meskipun proses pembutan hingga siap untuk digunakan sangatlah rumit, namun keuntungan yang didapat dari fleksibilitas sebuah IC dibandingkan dengan jika tidak menggunakan IC.

Jika ditilik dari sejak penemuan sebuah IC, teknologi IC boleh dibilang masih sangat muda. Belum genap setengah abad dari pertama kali diproduksi, IC telah berperan penting dalam peradaban manusia. Seperti komputer misalnya, yang proses utamanya dikontrol oleh ratusan IC. Komputer merupakan hal penting dalam mendukung perkembangan teknologi lainnya. Sudah sepantasnya kita mengucap syukur kepada Tuhan, yang telah mengizinkan perkembangan teknologi terjadi begitu pesatnya, yang akhirnya membawa kemudahan bagi umat manusia.

Sejarah Penemuan Integrated Circuit (IC) : elektro

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