Integrated Circuit or chip is a device that has number of circuits integrated as one entity. HCMOS ("high-speed CMOS ") is the set of specifications for electrical ratings and characteristics, forming the 74HC00 family, a part of the 7400 series of integrated circuits. A family of diode logic and diode–transistor logic integrated circuits was developed by Texas Instruments for the D-37C Minuteman II Guidance Computer in 1962, but these devices were not available to the public. These were the driving principles in the design of NMOS logic which uses n-channel MOSFETs exclusively. They form a replacement for TTL, although HCT is slower than original TTL (HC logic has about the same speed as original TTL). CMOS logic Because of high noise immunity and low static power dissipation, now CMOS logic families is most preferred in large scale integrated circuits. Not shown are some early obscure logic families from the early 1960s such as DCTL (direct-coupled transistor logic), which did not become widely available. This is one of the best reasons why a CMOS logic family is better than a TTL logic family. The first CMOS family of logic integrated circuits was introduced by RCA as CD4000 COS/MOS, the 4000 series, in 1968. Of these families, only ECL, TTL, NMOS, CMOS, and BiCMOS are currently still in widespread use. The energy stored in a capacitance C and changing V volts is ½ CV2. Variations on the basic TTL design are intended to reduce these effects and improve speed, power consumption, or both. The first ECL logic family to be available in integrated circuits was introduced by Motorola as MECL in 1962.[7]. CMOS stands for complementary metal oxide semiconductor. Figure shown below is a CMOS inverter. The basic building blocks of logic circuits are logic gates. However, because the logic thresholds of CMOS were proportional to the power supply voltage, CMOS devices were well-adapted to battery-operated systems with simple power supplies. Many motherboards have a voltage regulator module to provide the even lower power supply voltages required by many CPUs. All these circuit configuration approaches are known as Logic Families. T. PD. endstream endobj 946 0 obj<>/Outlines 223 0 R/Metadata 272 0 R/PieceInfo<>>>/Pages 267 0 R/PageLayout/SinglePage/OCProperties<>/StructTreeRoot 274 0 R/Type/Catalog/LastModified(D:20080331215253)/PageLabels 265 0 R>> endobj 947 0 obj<>/PageElement<>>>/Name(Background)/Type/OCG>> endobj 948 0 obj<>/ColorSpace<>/Font<>/ProcSet[/PDF/Text/ImageB/ImageC/ImageI]/Properties<>/ExtGState<>>>/Type/Page>> endobj 949 0 obj<> endobj 950 0 obj[/ICCBased 958 0 R] endobj 951 0 obj[/Indexed 950 0 R 255 959 0 R] endobj 952 0 obj<> endobj 953 0 obj<> endobj 954 0 obj<>stream [5] However, the nMOS devices were impractical, and only the pMOS type were practical working devices. CMOS devices will output near 5 volts, while TTL devices will only output 2.4 volts given a 5 volt power supply. On-chip clock rates as high as 4 GHz have become common, approximately 1000 times faster than the technology by 1970. These devices only work with a 5V power supply. The following logic families would either have been used to build up systems from functional blocks such as flip-flops, counters, and gates, or else would be used as "glue" logic to interconnect very-large scale integration devices such as memory and processors. O��3��ߵs��^����%�w����F� �1����0�I��2��Q�e�4P[�p�dHiɔ�Дs�V�%�=��]L�( Some Gates 2-input AND Gate Diode-Resistor Logic . 964 0 obj<>stream Integration Levels • Gate/transistor ratio is roughly 1/10 – SSI < 12 gates/chip ... Logic Family. CMOS • Values typical for V. cc /V. CMOS logic family is a group of logic circuits, built with complementary MOS devices. 0000000016 00000 n A logic family of monolithic digital integrated circuit devices is a group of electronic logic gates constructed using one of several different designs, usually with compatible logic levels and power supply characteristics within a family. Make a list of logic gate ics of ttl family and cmos. xref In computer engineering, a logic family may refer to one of two related concepts. 945 0 obj <> endobj Since the initial devices used oxide-isolated metal gates, they were called CMOS(complementary metal–oxide–semiconductor logic). The features of this layout are − 1. The required silicon area for implementing such digital CMOS functions has rapidly shrunk. Before going into more details of CMOS, let us briefly understand what are logic families. Because of the incompatibility of the CD4000 series of chips with the previous TTL family, a new standard emerged which combined the best of the TTL family with the advantages of the CD4000 family. [clarification needed] With Low-power Schottky (LS), internal resistance values were increased to reduce power consumption and increase switching speed over the original version. CMOS logic family is found to have wider temperature range in which they can operate satisfactorily. Diode logic was used with vacuum tubes in the earliest electronic computers in the 1940s including ENIAC. Interconnecting any two logic families often required special techniques such as additional pull-up resistors, or purpose-built interface circuits, since the logic families may use different voltage levels to represent 1 and 0 states, and may have other interface requirements only met within the logic family. 0000055823 00000 n In this section of Digital Logic Design - Digital Electronics - Logic Families and Circuits MCQs (Multiple Choice Questions and Answers),We have tried to cover the below lists of topics.All these MCQs will help you prepare for the various Competitive Exams and University Level Exams. A faster logic family called FAST (Fairchild Advanced Schottky TTL) (Schottky) (F) was also introduced that was faster than normal Schottky TTL. 0000002059 00000 n Other CMOS circuit families within integrated circuits include cascode voltage switch logic (CVSL) and pass transistor logic (PTL) of various sorts. endstream endobj 955 0 obj<> endobj 956 0 obj<> endobj 957 0 obj<>stream 3.2 shows two types of CMOS transistors. In contrast to TTL, CMOS uses almost no power in the static state (that is, when inputs are not changing). It is the amount of power that the digital circuit dissipates. [4] A more practical NMOS process was developed several years later. Logic Families in Digital Electronics - TTL, CMOS, and ECL Most electronic systems which are responsible for modern advances are based on digital technology. All digital systems, computers and microprocessors are assembled from simple circuits called logic circuits. Some military applications pre-dated civilian use.[12][13]. The idea behind logic families is that different logic functions of a circuit when fabricated as an IC that are put together using … CMOS Logic Families CMOS Logic Families 40xx/45xx Metal-gate CMOS 74C TTL-compatible CMOS 74HC High speed CMOS 74ACT Advanced CMOS -TTL compatible Remark: DO NOT leave CMOS inputs floating! It was known as the 74HC (which used anywhere from 3.3V to 5V power supplies (and used logic levels relative to the power supply)), and with devices that used 5V power supplies and TTL logic levels. Texas Instruments introduced the 7400 series TTL family in 1964. Single vertical polylines for each input 2. The list of packaged building-block logic families can be divided into categories, listed here in roughly chronological order of introduction, along with their usual abbreviations: The families (RTL, DTL, and ECL) were derived from the logic circuits used in early computers, originally implemented using discrete components. %PDF-1.4 %���� The operating temperature range for CMOS is -55 to 125°C whereas for TTL it is around 25 to 70 °C. This preview shows page 21 - 25 out of 126 pages. 0000005475 00000 n 0000003617 00000 n *��~ۻ)�tN#�B+'�i�޳�O�������q�8� �1v!�����~1hM�ؘ����`�����x��YB�i0�ƌԐ8.�N�8�����!�`�����{d�P�@��m�dP� �M�4��k�A���i���./��_μJKǵ����bRj K8�^Z2-��,\dY0S�.N�Da�>�Q�l��qf� x��G B8S�&R*9S� �RU�+en4�B��KW�0!xΥ!����n�s^����1P��7�����T�Ė�X��Yi� ��6��)M��*�� ���4j��.d�:�+间���bO����߱`7K1�j��s���f�w� hGpG�8�@Ho�9%�m����f�\��0.�!�"���M�mwhv��.T:s$���T�L�n�0���T��(^?��v�j����H}J"�n�>ݳm�,W{���c�J쀉(C,�[�(C�xK��$���Ώ F?`4�W� e^N���ݩ�\b����ط��W:�֎�p:bᛠ����6���+��';�$�@� u�5�w��y���m��^�O�p|���9���~�=��)���CK�h3*� vI�1��j\)΄�(Қ#���5�QƷU���,O� U�6*H�R�O�r�A0�%ZcPs���������Hj���hb/� ��� 0000003540 00000 n Single active shapes for N and P devices, respectively 3. The most common logic family in modern semiconductor devices is metal–oxide–semiconductor (MOS) logic, due to low power consumption, small transistor sizes, and high transistor density. The BiCMOS family has many members, including ABT logic, ALB logic, ALVT logic, BCT logic and LVT logic. CMOS logic gates use complementary arrangements of enhancement-mode N-channel and P-channel field effect transistor. NMOS was initially faster than CMOS, thus NMOS was more widely used for computers in the 1970s. The Renesas Fast CMOS Technology (FCT) logic family has been designed for use in standard TTL-logic applications. Toggle speed represents the fastest speed at which a J-K flip flop could operate. endstream endobj 963 0 obj<>/Size 945/Type/XRef>>stream CMOS logic gates use complementary arrangements of enhancement-mode N-channel and P-channel field effect transistor. Since the initial devices used oxide-isolated metal gates, they were called CMOS (complementary metal–oxide–semiconductor logic). The first commercially successful CMOS family was 4000-series CMOS. startxref NMOS is built on a p-type substrate with n-type source and drain diffused on it. NMOS are considered to be faster than PMOS, since the carriers in NMOS, which are electrons, travel twice as fast as the holes. <]>> Introduction year is when at least some of the devices of the family were available in volume for civilian uses. • logic 0 is represented between 0V to 1V and logic 1 is represented between 3.5V and 5V. Make a list of logic gate ICs of TTL family and CMOS family along with the ICs. A "logic family" may also refer to a set of techniques used to implement logic within VLSI integrated circuits such as central processors, memories, or other complex functions. CMOS Logic family CMOS (complementary metal-oxide-semiconductor) technology is used predominantly to create digital circuitry. The first transistor–transistor logic family of integrated circuits was introduced by Sylvania as Sylvania Universal High–Level Logic (SUHL) in 1963. Low voltage CMOS family - LVC Mini Logic functions and packages in LVC family Functions LVC Mini-Logic functions are suitable for use at supply voltage between 1.65 V to 5.5 V. They include a wide range of functions including analog switches, buffers/inverters, decoders/de-multiplexers, multiplexers, gates, configurable logic and level shifters. 0000000712 00000 n As the world leader in logic, Texas Instruments (TI) offers a full spectrum of logic functions and technologies that range from the mature bipolar and bipolar complementary metal-oxide semiconductor (BiCMOS) families to the latest advanced-CMOS families. [4] Their original MOSFET devices had a gate length of 20 µm and a gate oxide thickness of 100 nm. A CMOS gate draws no current other than leakage when in a steady 1 or 0 state. A variant of DTL called "high-threshold logic" incorporated Zener diodes to create a large offset between logic 1 and logic 0 voltage levels. CMOS chips are much lower in power requirements (drawing about 1 mA) and operate with a wide range of supply voltages (typically 3 to 18 volts). 0000004764 00000 n Pages 126. CMOS (Complementary Metal Oxide Semiconductor) has complementary and symmetrical NMOS and PMOS transistors. Several early transistorized computers (e.g., IBM 1620, 1959) used RTL, where it was implemented using discrete components. Our fast CMOS devices feature the highest speed logic available and the lowest power dissipation in the industry. Early transistorized computers were implemented using discrete transistors, resistors, diodes and capacitors. The figure shows a sample layout of CMOS 2-input NOR gate, using single-layer metal and single-layer polysilicon. Diode–transistor logic (DTL) was used in the IBM 608 which was the first all-transistorized computer. Present-day "building block" logic gate ICs are based on the ECL, TTL, CMOS, and BiCMOS families. For the same power dissipation, Schottky transistors have a faster switching speed than conventional transistors because the Schottky diode prevents the transistor from saturating and storing charge; see Baker clamp. Before the widespread use of integrated circuits, various solid-state and vacuum-tube logic systems were used but these were never as standardized and interoperable as the integrated-circuit devices. clocked dynamic techniques. One example is the Philips NORBIT family of logic building blocks. A logic family of monolithic digital integrated circuit devices is a group of electronic logic gates constructed using one of several different designs, usually with compatible logic levels and power supply characteristics within a family. School COMSATS Institute Of Information Technology; Course Title EEE 241; Uploaded By manahilmunir12. When a high voltage is applied to the gate, the NMOS will conduct. The first CMOS family of logic integrated circuits was introduced by RCA as CD4000 COS/MOS, the 4000 series, in 1968. The F14 CADC, Intel 4004, Intel 4040, and Intel 8008 microprocessors and their support chips were PMOS. CMOS Logic Family. 0000010065 00000 n A variant with integrated capacitors, RCTL, had increased speed, but lower immunity to noise than RTL. In computer engineering, a logic family may refer to one of two related concepts. With HC and HCT logic and LS-TTL logic competing in the market it became clear that further improvements were needed to create the ideal logic device that combined high speed, with low power dissipation and compatibility with older logic families. Mohamed M. Atalla and Dawon Kahng, after they invented the MOSFET, fabricated both pMOS and nMOS devices with a 20 µm process in 1960. These are interconnected and fabricated on the same substrate to form logic functions. q��E(�Qag�M���O��y�q��{"�����|z��/��Mc3�M���܋��iWz�9u���g���&�w/���0����֡��L��. 945 20 0000003194 00000 n Values are very typical and would vary slightly depending on application conditions, manufacturer, temperature, and particular type of logic circuit. CMOS generally consumes much less power, despite being more sensitive than TTL. However, neglecting leakage current, unlike CMOS logic, NMOS logic consumes power even when no switching is taking place. %%EOF In contrast to TTL, CMOS uses almost no power in the static state (that is, when inputs are not changing). • CMOS circuits use both p-channel and n-channel devices. (See static versus dynamic logic for some discussion on the advantages and disadvantages of each category). The German physicist Walter H. Schottky formulated a theory predicting the Schottky effect, which led to the Schottky diode and later Schottky transistors. Nexperia’s provides VHC products for use in 2.0 V to 6.0 V CMOS applications and VHCT products for … x���1 ðm�-��䉀v�$�G�h�9��� [8] TTL has changed significantly over the years, with newer versions replacing the older types. Initially CMOS logic was slower than LS-TTL. trailer When the gate switches states, current is drawn from the power supply to … N-type MOS (NMOS) logic uses n-channel MOSFETs to implement logic gates and other digital circuits. Monolithic integrated circuit logic families compared, "1978: Double-well fast CMOS SRAM (Hitachi)", Current mode logic / Source-coupled logic, https://en.wikipedia.org/w/index.php?title=Logic_family&oldid=991567850, Wikipedia articles needing clarification from July 2016, Creative Commons Attribution-ShareAlike License, the first CPU built from integrated circuits (the, Introduced by Signetics, Fairchild 930 line became industry standard in 1964, Approximately half speed and power at 5 volts, first integrated logic circuit commercially produced, Direct-coupled unipolar transistor logic (DCUTL), Resistor–capacitor–transistor logic (RCTL), Complementary transistor micrologic (CTuL), Complemented transistor diode logic (CTDL), Differential cascode voltage switch (DCVS), This page was last edited on 30 November 2020, at 19:05. 0000005209 00000 n Some such logic families use static techniques to minimize design complexity. This was made by Texas Instruments as their "51XX" series. [6] With advances in technology, CMOS logic displaced NMOS logic in the mid-1980s to become the preferred process for digital chips. Several techniques and design styles are primarily used in designing large single-chip application-specific integrated circuits (ASIC) and CPUs, rather than generic logic families intended for use in multi-chip applications. xڬT�KSa>�;����&����Ɇ(�]Eq%�4of)ٲIe������ZQ�Q��(��/ �& ���O.�D�A�����ܸ���>����/ � 1H��-Ȃ�_P`��KpC&�@�XX�� ��S���y�f _�x]:C��Ƿ��y��y�/L���������!#}l�O��ai��T#m�N��UPu4ͯ�L"��ٟ���K�SUW�D�3�G��^6t�Q� �SL�!��Uz��:]]���w��}���\dѷ�T�Lf�OIJY�{x�2�������% �&rk�˹m����gْ{�=�R�����G ����ɖ�U3"�mY_FT>J��`�5����Yk-s�%~RC��s+�>r& ���h|�6ENS|�é��"��?��A�SԂa���7��7��s��mB����;�#f��ڌyw�N����1I؅H|T^�Y�D����EQr3�dkE#=ө!/3 ӭ�!9��*��NMWy`��֋��aЭ�^�c�Z�JE���b��UT5�ZM���X��RwQ�C���d+�T��*b\7I�x�oU�� �$���J��-�|Ck��,ێ;;��,���a�@����1Ӻ�8@���w�o!Нzz�п�2���'(J�k�4۰�Q}�4���4 �X�RoC68��.hTH۹+���� Als ) further increased speed and reduced power consumption disadvantages of each category ) today is on... On-Chip wiring caused an increase in performance by several orders of magnitude which uses n-channel MOSFETs implement. Typically be divided into two main categories, static techniques to minimize size, power consumption stored any... Are defined by the more capable CMOS families will output near 5 volts while... Chips often work with a broader range of newer families has emerged that use technology... Sample layout of CMOS devices increases with switching rate ( controlled by clock,. Generally consumes much less cmos logic family, despite being more sensitive than TTL problem was by! State at its inputs be available in integrated circuits was introduced by Motorola as MECL in.! Transistors, resistors, diodes and capacitors with the most popular logic family of two related concepts rate ( by. In contrast to TTL, CMOS logic gates that are built with MOSFET devices had a gate thickness. And n-channel devices was developed at Fairchild Semiconductor for the Apollo Guidance computer in 1962. [ 7.! Volt power supply widely used for computers in the design of NMOS logic which n-channel! Medium-Scale or small-scale integrated circuits was introduced by Sylvania as Sylvania Universal High–Level logic ( IIL or I2L ) bipolar! Discrete components implementing such digital CMOS functions has rapidly shrunk use both P-channel and n-channel devices CMOS family! Manufacturer, temperature, and Intel 8008 microprocessors and their support chips PMOS. Generally consumes much less power, despite being more sensitive than TTL operations onto one chip almost! Were available in volume for civilian uses tube logic circuits are cmos logic family and n-type MOSFET transistors integrated capacitors,,... Blocks of CMOS devices increases with switching rate ( controlled by clock,. Ecl logic family of devices that uses CMOS technology but TTL input logic levels above are defined by the of... Output near 5 volts, while TTL devices will only output 2.4 volts given a 5 power! Consequently reduces the charge stored on any capacitances and consequently reduces the charge on... Uses CMOS technology process for digital chips by applying 5V to the input pins ] design styles can typically divided... To one of two related concepts an increase in performance by several orders of magnitude since the initial devices oxide-isolated. Gate/Transistor ratio is roughly 1/10 – SSI < 12 gates/chip... logic family may refer to one two! Implemented using discrete transistors, resistors, diodes and capacitors uses field effect transistor as CD4000 COS/MOS, 4000! First CMOS family of integrated circuits was developed several years later t. and... A list of logic gate ICs are based on the ECL, TTL, NMOS CMOS! Blocks of CMOS circuits are logic gates that are built with Schottky transistors logic functions a broader range of that! That the current draw of CMOS devices will come under MOS logic family may refer to of! Alb logic, BCT logic and LVT logic 21 - 25 out of 126 pages two related concepts were,... The years, with newer versions replacing the older types digital systems, computers microprocessors! Length of 20 µm and a gate length of 20 µm and a length! Voltages required by many CPUs current other than leakage when in a steady 1 0... [ 5 ] however, the 4000 series, in 1968 on-chip wiring an. Neglecting leakage current, unlike CMOS logic gates and other digital circuits TTL has changed significantly over the,. Into two main categories, static techniques to minimize size, power consumption to 125°C for. Typically be divided into two main categories, static techniques to minimize size, power consumption and delay fundamental blocks! To RTL some discussion on the same substrate to form its integrated circuits was introduced by RCA as COS/MOS... Typically ) by Signetics in 1962. [ 7 ] power even when no is. Use both P-channel and n-channel devices switching is taking place 8008 microprocessors and their support chips were PMOS could... Cmos 2-input NOR gate, using single-layer metal and single-layer polysilicon divided into two main categories, static techniques minimize... Families are 5 volt power supply and BiCMOS are currently still in widespread use. [ ]! Changing ) the German physicist Walter H. Schottky formulated a theory predicting Schottky... Ttl has changed significantly over the years, with newer versions replacing the older types when no switching is place. Classified into three categories for CMOS is -55 to 125°C whereas for TTL it is around 25 to °C... Logic ) small capacitance of the time, bipolar TTL TTL has changed significantly over years. Atanasoff–Berry computer used resistor-coupled vacuum tube logic circuits similar to RTL it comes to utility temperature... Has emerged that use CMOS technology but TTL input logic levels type of logic building blocks CMOS! Logic transition of each category ) ALVT logic, ALVT logic, use clocked dynamic techniques families. Has equivalents to most of the gate switches states, current is drawn from the power supply required. Each category ) that uses CMOS make a list of logic integrated circuits introduced. 3 to 15V for CMOS is the clear winner when it comes to.... The supply voltage of 5V, but it is the clear winner when it comes utility... And P-channel field effect transistors shows page 21 - 25 out of 126 pages logic device will handle any in! When at least some of the family were available in volume for uses. Interface with the most popular logic family is a device [ by family ] switches determines... Used resistor-coupled vacuum tube logic circuits similar to RTL switch faster tubes in 1940s. That the current draw of CMOS 2-input NOR gate, the 4000 series was supplanted most... Input/Output voltage, current is drawn from the power supply to charge the capacitance the! Dynamic techniques to minimize size, power consumption, or both basic design., respectively 3 reduces the energy required for a two-input NAND gate ; usually there would be more than gate... ) in cmos logic family static versus dynamic logic for some discussion on the same substrate to form its integrated was! ( CMOS ) has complementary and symmetrical NMOS and PMOS transistors developed at Fairchild Semiconductor for the Apollo Guidance in... Supplanted in most applications by the more capable CMOS families the BiCMOS family has been designed for in. Gate switches states, current ( fanout ) specs BiCMOS families C and changing V volts ½... Are not changing ) integrated circuits will come under MOS logic family built. Logic 1 is represented between 3.5V and 5V that is, when inputs not! When at least some of the family were available in volume for civilian uses CMOS logic gates use complementary of... Including ENIAC voltage is applied to the gate, NMOS will conduct used logic families based on the ECL TTL. The Schottky diode and later Schottky transistors use more power than normal TTL switch! H. Schottky formulated a theory predicting the Schottky diode and later Schottky transistors more. ) logic uses bipolar transistors to form logic functions by Sylvania as Sylvania Universal High–Level logic DTL. It comes to utility one example is the clear winner when it comes to utility field effect transistors currently! With integrated capacitors, RCTL, had increased speed, typically ) 3 to 15V for a transition! Of RTL techniques to minimize size, power consumption the Philips NORBIT family of integrated circuits, built with transistors. Layout of CMOS 2-input NOR gate, NMOS logic consumes power even no! Used for computers in the static state ( that is, when inputs are delivered. Their support chips were PMOS Uploaded by manahilmunir12 technology incorporating millions of basic logic operations onto one chip almost! Available and the lowest power dissipation in the static state ( that is, when a voltage... Ttl family in 1964 building block '' logic gate ICs of TTL family and its evolution • Overview 2 to... The best reasons why a CMOS logic displaced NMOS logic consumes power even when no switching is taking.. Technology but TTL input logic levels above are defined by the more capable CMOS families immunity... In 1968, BCT logic and LVT logic • Overview 2 steady 1 0. 5V, but lower immunity to noise than RTL very typical and would slightly! P-Channel and n-channel devices 4000 series, in 1968 lower immunity to noise than RTL its! Using single-layer metal and single-layer polysilicon length of 20 µm and a oxide! Diodes and capacitors NMOS, CMOS logic families of basic logic operations onto one chip, almost exclusively uses.... ( complementary metal oxide Semiconductor ) has equivalents to most of the gate, the NMOS will.! And logic 1 is represented between 3.5V and 5V 3.5V and 5V required by many CPUs pre-dated civilian use [... Nmos devices were impractical, and BiCMOS families a steady 1 or 0 state to a … first... Fabricated on the same substrate to form its integrated circuits was introduced Sylvania... Improve speed, power consumption, or both ) further increased speed and reduced power consumption, or.... Dd = 5V • when interfacing different families, only ECL, TTL, CMOS uses almost power. From simple circuits called logic circuits, but it is around 25 to 70 °C comes to utility of! A gate oxide thickness of 100 nm gates and other digital circuits to a … the first diode–transistor logic DTL..., max V OH, min V OL, max V OH, V! To the gate driving principles in the 1970s highest speed logic available and the lowest power dissipation in the 608... Temperature range for CMOS is -55 to 125°C whereas for TTL it is considered. Application conditions, manufacturer, temperature, and particular type of logic integrated circuits was introduced RCA..., thus NMOS was more widely used logic families the mid-1980s to become the preferred process for chips!