In computing , multi-touch is technology that enables a surface (a touchpad or touchscreen ) to recognize the presence of more than one point of contact with the surface at the same time. The origins of multitouch began at CERN , MIT , University of Toronto , Carnegie Mellon University and Bell Labs in the 1970s. CERN started using multi-touch screens as early as 1976 for the controls of the Super Proton Synchrotron . Capacitive multi-touch displays were popularized by Apple 's iPhone in 2007. Multi-touch may be used to implement additional functionality, such as pinch to zoom or to activate certain subroutines attached to predefined gestures using gesture recognition .
98-422: The Magic Trackpad is a multi-touch and force touch trackpad produced by Apple Inc. The first generation version was released on July 27, 2010, and featured a trackpad 80% larger than the built-in trackpad found on the then-current MacBook family of laptops. A redesigned second generation version, initially marketed as Magic Trackpad 2 , was released on October 13, 2015. The first generation Magic Trackpad
196-520: A 3 μm process . The Hitachi HM6147 chip was able to match the performance (55/70 ns access) of the Intel 2147 HMOS chip, while the HM6147 also consumed significantly less power (15 mA ) than the 2147 (110 mA). With comparable performance and much less power consumption, the twin-well CMOS process eventually overtook NMOS as the most common semiconductor manufacturing process for computers in
294-419: A 350 nm CMOS process, while Hitachi and NEC commercialized 250 nm CMOS. Hitachi introduced a 160 nm CMOS process in 1995, then Mitsubishi introduced 150 nm CMOS in 1996, and then Samsung Electronics introduced 140 nm in 1999. In 2000, Gurtej Singh Sandhu and Trung T. Doan at Micron Technology invented atomic layer deposition High-κ dielectric films , leading to
392-474: A "tap-click" gesture to select while maintaining location with another finger are also described. In 1991, Pierre Wellner advanced the topic publishing about his multi-touch "Digital Desk", which supported multi-finger and pinching motions. Various companies expanded upon these inventions in the beginning of the twenty-first century. Between 1999 and 2005, the company Fingerworks developed various multi-touch technologies, including Touchstream keyboards and
490-466: A 20 μm semiconductor manufacturing process before gradually scaling to a 10 μm process over the next several years. CMOS technology was initially overlooked by the American semiconductor industry in favour of NMOS, which was more powerful at the time. However, CMOS was quickly adopted and further advanced by Japanese semiconductor manufacturers due to its low power consumption, leading to
588-545: A CMOS IC chip for a Seiko quartz watch in 1969, and began mass-production with the launch of the Seiko Analog Quartz 38SQW watch in 1971. The first mass-produced CMOS consumer electronic product was the Hamilton Pulsar "Wrist Computer" digital watch, released in 1970. Due to low power consumption, CMOS logic has been widely used for calculators and watches since the 1970s. The earliest microprocessors in
686-460: A CMOS circuit. This example shows a NAND logic device drawn as a physical representation as it would be manufactured. The physical layout perspective is a "bird's eye view" of a stack of layers. The circuit is constructed on a P-type substrate. The polysilicon , diffusion, and n-well are referred to as "base layers" and are actually inserted into trenches of the P-type substrate. (See steps 1 to 6 in
784-482: A CMOS device: P = 0.5 C V 2 f {\displaystyle P=0.5CV^{2}f} . Since most gates do not operate/switch at every clock cycle , they are often accompanied by a factor α {\displaystyle \alpha } , called the activity factor. Now, the dynamic power dissipation may be re-written as P = α C V 2 f {\displaystyle P=\alpha CV^{2}f} . A clock in
882-443: A PMOS transistor creates low resistance between its source and drain contacts when a low gate voltage is applied and high resistance when a high gate voltage is applied. On the other hand, the composition of an NMOS transistor creates high resistance between source and drain when a low gate voltage is applied and low resistance when a high gate voltage is applied. CMOS accomplishes current reduction by complementing every nMOSFET with
980-401: A brief spike in power consumption and becomes a serious issue at high frequencies. The adjacent image shows what happens when an input is connected to both a PMOS transistor (top of diagram) and an NMOS transistor (bottom of diagram). Vdd is some positive voltage connected to a power supply and Vss is ground. A is the input and Q is the output. When the voltage of A is low (i.e. close to Vss),
1078-412: A capacitive touch screen with a fixed number of programmable buttons presented on a display. The screen was to consist of a set of capacitors etched into a film of copper on a sheet of glass, each capacitor being constructed so that a nearby flat conductor, such as the surface of a finger, would increase the capacitance by a significant amount. The capacitors were to consist of fine lines etched in copper on
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#17328633384361176-456: A close relative of CMOS. He invented complementary flip-flop and inverter circuits, but did no work in a more complex complementary logic. He was the first person able to put p-channel and n-channel TFTs in a circuit on the same substrate. Three years earlier, John T. Wallmark and Sanford M. Marcus published a variety of complex logic functions implemented as integrated circuits using JFETs , including complementary memory circuits. Frank Wanlass
1274-543: A device similar to the Microsoft Surface was shown. It took up an executive's entire desk and was used to communicate with the Master Control computer . In the 2002 film Minority Report , Tom Cruise uses a set of gloves that resemble a multi-touch interface to browse through information. In the 2005 film The Island , another form of a multi-touch computer was seen where the professor, played by Sean Bean , has
1372-422: A finger or an object touches the surface, causing the light to scatter, the reflection of which is caught with sensors or cameras that send the data to software that dictates response to the touch, depending on the type of reflection measured. Optical technologies include: Acoustic and radio-frequency wave-based technologies include: Multi-touch touchscreen gestures enable predefined motions to interact with
1470-458: A high density of logic functions on a chip. It was primarily for this reason that CMOS became the most widely used technology to be implemented in VLSI chips. The phrase "metal–oxide–semiconductor" is a reference to the physical structure of MOS field-effect transistors , having a metal gate electrode placed on top of an oxide insulator, which in turn is on top of a semiconductor material . Aluminium
1568-399: A means of information or exhibit display. Multi-touch has been implemented in several different ways, depending on the size and type of interface. The most popular form are mobile devices, tablets , touchtables and walls. Both touchtables and touch walls project an image through acrylic or glass, and then back-light the image with LEDs. Touch surfaces can also be made pressure-sensitive by
1666-436: A multi-touch desktop to organize files, based on an early version of Microsoft Surface (not be confused with the tablet computers which now bear that name). In 2007, the television series CSI: Miami introduced both surface and wall multi-touch displays in its sixth season. Multi-touch technology can be seen in the 2008 James Bond film Quantum of Solace , where MI6 uses a touch interface to browse information about
1764-431: A pMOSFET and connecting both gates and both drains together. A high voltage on the gates will cause the nMOSFET to conduct and the pMOSFET not to conduct, while a low voltage on the gates causes the reverse. This arrangement greatly reduces power consumption and heat generation. However, during the switching time, both pMOS and nMOS MOSFETs conduct briefly as the gate voltage transitions from one state to another. This induces
1862-512: A rectangular piece of silicon of often between 10 and 400 mm . CMOS always uses all enhancement-mode MOSFETs (in other words, a zero gate-to-source voltage turns the transistor off). CMOS circuits are constructed in such a way that all P-type metal–oxide–semiconductor (PMOS) transistors must have either an input from the voltage source or from another PMOS transistor. Similarly, all NMOS transistors must have either an input from ground or from another NMOS transistor. The composition of
1960-419: A response to the gesture event. In the past few years, several companies have released products that use multi-touch. In an attempt to make the expensive technology more accessible, hobbyists have also published methods of constructing DIY touchscreens. Capacitive technologies include: Resistive technologies include: Optical touch technology is based on image sensor technology. It functions when
2058-414: A sheet of glass – fine enough (80 μm) and sufficiently far apart (80 μm) to be invisible. In the final device, a simple lacquer coating prevented the fingers from actually touching the capacitors. In the same year, MIT described a keyboard with variable graphics capable of multi-touch detection. In the early 1980s, The University of Toronto 's Input Research Group were among the earliest to explore
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#17328633384362156-567: A shift key while typing another were not possible. Exceptions to these were a "cross-wire" multi-touch reconfigurable touchscreen keyboard/display developed at the Massachusetts Institute of Technology in the early 1970s and the 16 button capacitive multi-touch screen developed at CERN in 1972 for the controls of the Super Proton Synchrotron that were under construction. In 1976 a new x-y capacitive screen, based on
2254-413: A small period of time in which current will find a path directly from V DD to ground, hence creating a short-circuit current , sometimes called a crowbar current. Short-circuit power dissipation increases with the rise and fall time of the transistors. This form of power consumption became significant in the 1990s as wires on chip became narrower and the long wires became more resistive. CMOS gates at
2352-425: A system has an activity factor α=1, since it rises and falls every cycle. Most data has an activity factor of 0.1. If correct load capacitance is estimated on a node together with its activity factor, the dynamic power dissipation at that node can be calculated effectively. Since there is a finite rise/fall time for both pMOS and nMOS, during transition, for example, from off to on, both the transistors will be on for
2450-443: A trade-off for devices to become slower. To speed up designs, manufacturers have switched to constructions that have lower voltage thresholds but because of this a modern NMOS transistor with a V th of 200 mV has a significant subthreshold leakage current. Designs (e.g. desktop processors) which include vast numbers of circuits which are not actively switching still consume power because of this leakage current. Leakage power
2548-467: Is optical touch technology , based on image sensor technology. In computing , multi-touch is technology which enables a touchpad or touchscreen to recognize more than one or more than two points of contact with the surface. Apple popularized the term "multi-touch" in 2007 with which it implemented additional functionality, such as pinch to zoom or to activate certain subroutines attached to predefined gestures . The two different uses of
2646-471: Is a significant portion of the total power consumed by such designs. Multi-threshold CMOS (MTCMOS), now available from foundries, is one approach to managing leakage power. With MTCMOS, high V th transistors are used when switching speed is not critical, while low V th transistors are used in speed sensitive paths. Further technology advances that use even thinner gate dielectrics have an additional leakage component because of current tunnelling through
2744-456: Is attached to the touch surface. Usually, separate companies make the ASIC and screen that combine into a touch screen; conversely, a touchpad's surface and ASIC are usually manufactured by the same company. There have been large companies in recent years that have expanded into the growing multi-touch industry, with systems designed for everything from the casual user to multinational organizations. It
2842-405: Is connected to V SS and an N-type n-well tap is connected to V DD to prevent latchup . CMOS logic dissipates less power than NMOS logic circuits because CMOS dissipates power only when switching ("dynamic power"). On a typical ASIC in a modern 90 nanometer process, switching the output might take 120 picoseconds, and happens once every ten nanoseconds. NMOS logic dissipates power whenever
2940-457: Is connected together in metal (illustrated in cyan coloring). Connections between metal and polysilicon or diffusion are made through contacts (illustrated as black squares). The physical layout example matches the NAND logic circuit given in the previous example. The N device is manufactured on a P-type substrate while the P device is manufactured in an N-type well (n-well). A P-type substrate "tap"
3038-466: Is now common for laptop manufacturers to include multi-touch touchpads on their laptops, and tablet computers respond to touch input rather than traditional stylus input and it is supported by many recent operating systems . A few companies are focusing on large-scale surface computing rather than personal electronics, either large multi-touch tables or wall surfaces. These systems are generally used by government organizations, museums, and companies as
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3136-425: Is reduced and the users' hands don't obstruct the display. Instead of placing windows all over the screen, the windowing manager, Con10uum, uses a linear paradigm, with multi-touch used to navigate between and arrange the windows. An area at the right side of the touch screen brings up a global context menu, and a similar strip at the left side brings up application-specific menus. An open source community preview of
3234-666: Is seated or the floorpad on which the user is standing. In 2007, NORTD labs open source system offered its CUBIT (multi-touch) . Small-scale touch devices rapidly became commonplace in 2008. The number of touch screen telephones was expected to increase from 200,000 shipped in 2006 to 21 million in 2012. In May 2015, Apple was granted a patent for a "fusion keyboard", which turns individual physical keys into multi-touch buttons. Apple has retailed and distributed numerous products using multi-touch technology, most prominently including its iPhone smartphone and iPad tablet. Additionally, Apple also holds several patents related to
3332-424: Is shown to be performing multiple multi-touch hand gestures on a large touch wall. In the 2009, the film District 9 the interface used to control the alien ship features similar technology. 10/GUI is a proposed new user interface paradigm. Created in 2009 by R. Clayton Miller, it combines multi-touch input with a new windowing manager . It splits the touch surface away from the screen, so that user fatigue
3430-465: Is that both low-to-high and high-to-low output transitions are fast since the (PMOS) pull-up transistors have low resistance when switched on, unlike the load resistors in NMOS logic. In addition, the output signal swings the full voltage between the low and high rails. This strong, more nearly symmetric response also makes CMOS more resistant to noise. See Logical effort for a method of calculating delay in
3528-447: Is the duality that exists between its PMOS transistors and NMOS transistors. A CMOS circuit is created to allow a path always to exist from the output to either the power source or ground. To accomplish this, the set of all paths to the voltage source must be the complement of the set of all paths to ground. This can be easily accomplished by defining one in terms of the NOT of the other. Due to
3626-546: Is the same height and angle of inclination as the Apple Wireless Keyboard, making them a good fit, in terms of size and style." In reviews of the second-generation Magic Trackpad, reviewers praised the new Force Touch functionality, better ergonomics over the Magic Mouse, and full compatibility with macOS and iPadOS, but noted its high price tag. Multi-touch Several uses of the term multi-touch resulted from
3724-518: Is used for constructing integrated circuit (IC) chips, including microprocessors , microcontrollers , memory chips (including CMOS BIOS ), and other digital logic circuits. CMOS technology is also used for analog circuits such as image sensors ( CMOS sensors ), data converters , RF circuits ( RF CMOS ), and highly integrated transceivers for many types of communication. In 1948, Bardeen and Brattain patented an insulated-gate transistor (IGFET) with an inversion layer. Bardeen's concept forms
3822-456: Is very small compared to sub threshold and tunnelling currents, so these may be neglected during power calculations. If the ratios do not match, then there might be different currents of PMOS and NMOS; this may lead to imbalance and thus improper current causes the CMOS to heat up and dissipate power unnecessarily. Furthermore, recent studies have shown that leakage power reduces due to aging effects as
3920-595: The Lightning connector for charging and pairing. Released in 2020, iPadOS 13.4 introduced mouse support to iPads for the first time, and supports all functionality of the second-generation Magic Trackpad. It was originally released in white, and was followed by a space gray version that was introduced with the iMac Pro in 2017 alongside a color-matching Magic Keyboard ; both were later made available as standalone purchases. Seven pastel models (red, pink, orange, yellow, green, blue, and purple) were introduced in 2021 to match
4018-431: The 1970s. The Intel 5101 (1 kb SRAM ) CMOS memory chip (1974) had an access time of 800 ns , whereas the fastest NMOS chip at the time, the Intel 2147 (4 kb SRAM) HMOS memory chip (1976), had an access time of 55/70 ns. In 1978, a Hitachi research team led by Toshiaki Masuhara introduced the twin-well Hi-CMOS process, with its HM6147 (4 kb SRAM) memory chip, manufactured with
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4116-485: The 1980s. In the 1980s, CMOS microprocessors overtook NMOS microprocessors. NASA 's Galileo spacecraft, sent to orbit Jupiter in 1989, used the RCA 1802 CMOS microprocessor due to low power consumption. Intel introduced a 1.5 μm process for CMOS semiconductor device fabrication in 1983. In the mid-1980s, Bijan Davari of IBM developed high-performance, low-voltage, deep sub-micron CMOS technology, which enabled
4214-462: The A or B inputs is low, one of the NMOS transistors will not conduct, one of the PMOS transistors will, and a conductive path will be established between the output and V dd (voltage source), bringing the output high. As the only configuration of the two inputs that results in a low output is when both are high, this circuit implements a NAND (NOT AND) logic gate. An advantage of CMOS over NMOS logic
4312-456: The CMOS device. Clamp diodes are included in CMOS circuits to deal with these signals. Manufacturers' data sheets specify the maximum permitted current that may flow through the diodes. Besides digital applications, CMOS technology is also used in analog applications. For example, there are CMOS operational amplifier ICs available in the market. Transmission gates may be used as analog multiplexers instead of signal relays . CMOS technology
4410-509: The CMU system was optical. In 1985, the canonical multitouch pinch-to-zoom gesture was demonstrated, with coordinated graphics, on CMU's system. In October 1985, Steve Jobs signed a non-disclosure agreement to tour CMU's Sensor Frame multi-touch lab. In 1990, Sears et al. published a review of academic research on single and multi-touch touchscreen human–computer interaction of the time, describing single touch gestures such as rotating knobs, swiping
4508-516: The Con10uum window manager was made available in November, 2009. CMOS Complementary metal–oxide–semiconductor ( CMOS , pronounced "sea-moss ", / s iː m ɑː s / , /- ɒ s / ) is a type of metal–oxide–semiconductor field-effect transistor (MOSFET) fabrication process that uses complementary and symmetrical pairs of p-type and n-type MOSFETs for logic functions. CMOS technology
4606-451: The MOSFET pair is always off, the series combination draws significant power only momentarily during switching between on and off states. Consequently, CMOS devices do not produce as much waste heat as other forms of logic, like NMOS logic or transistor–transistor logic (TTL), which normally have some standing current even when not changing state. These characteristics allow CMOS to integrate
4704-638: The Magic Trackpad 2, was released on October 13, 2015, alongside the Magic Keyboard and Magic Mouse 2 . It had 29% more surface area than the first generation model, features an enclosed wedge design, and adds support for Force Touch . It also provides haptic feedback via Apple's built-in Taptic Engine that is also used in MacBook trackpads. It includes a built-in rechargeable lithium-ion battery and uses
4802-450: The NMOS transistor's channel is in a high resistance state, disconnecting Vss from Q. The PMOS transistor's channel is in a low resistance state, connecting Vdd to Q. Q, therefore, registers Vdd. On the other hand, when the voltage of A is high (i.e. close to Vdd), the PMOS transistor is in a high resistance state, disconnecting Vdd from Q. The NMOS transistor is in a low resistance state, connecting Vss to Q. Now, Q registers Vss. In short,
4900-416: The PMOS transistors (top half) will conduct, and a conductive path will be established between the output and V ss (ground), bringing the output low. If both of the A and B inputs are low, then neither of the NMOS transistors will conduct, while both of the PMOS transistors will conduct, establishing a conductive path between the output and V dd (voltage source), bringing the output high. If either of
4998-433: The U.S. Patent and Trademark office declared that the "pinch-to-zoom" functionality was predicted by U.S. Patent # 7,844,915 relating to gestures on touch screens, filed by Bran Ferren and Daniel Hillis in 2005, as was inertial scrolling, thus invalidated a key claims of Apple's patent. In 2001, Microsoft's table-top touch platform, Microsoft PixelSense (formerly Surface) started development, which interacts with both
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#17328633384365096-405: The addition of a pressure-sensitive coating that flexes differently depending on how firmly it is pressed, altering the reflection. Handheld technologies use a panel that carries an electrical charge. When a finger touches the screen, the touch disrupts the panel's electrical field. The disruption is registered as a computer event (gesture) and may be sent to the software, which may then initiate
5194-537: The basis of CMOS technology today. The CMOS process was presented by Fairchild Semiconductor 's Frank Wanlass and Chih-Tang Sah at the International Solid-State Circuits Conference in 1963. Wanlass later filed US patent 3,356,858 for CMOS circuitry and it was granted in 1967. RCA commercialized the technology with the trademark "COS-MOS" in the late 1960s, forcing other manufacturers to find another name, leading to "CMOS" becoming
5292-414: The best performance per watt each year have been CMOS static logic since 1976. As of 2019, planar CMOS technology is still the most common form of semiconductor device fabrication, but is gradually being replaced by non-planar FinFET technology, which is capable of manufacturing semiconductor nodes smaller than 20 nm . "CMOS" refers to both a particular style of digital circuitry design and
5390-496: The capacitance touch screens developed in 1972 by Danish electronics engineer Bent Stumpe , was developed at CERN . This technology, allowing an exact location of the different touch points, was used to develop a new type of human machine interface (HMI) for the control room of the Super Proton Synchrotron particle accelerator. In a handwritten note dated 11 March 1972, Stumpe presented his proposed solution –
5488-511: The colors of the M1 iMac . Additionally, standalone purchases included a USB-C to Lightning cable instead of a USB-A cable. In 2022, the space gray color was replaced by a black-and-silver version which was previously only available bundled with the third-generation Mac Pro . On October 28, 2024, Apple released an updated Magic Trackpad that replaced the Lightning charging port with a USB-C port. Reviews of
5586-412: The concept of an inversion layer, forms the basis of CMOS technology today. A new type of MOSFET logic combining both the PMOS and NMOS processes was developed, called complementary MOS (CMOS), by Chih-Tang Sah and Frank Wanlass at Fairchild. In February 1963, they published the invention in a research paper . In both the research paper and the patent filed by Wanlass, the fabrication of CMOS devices
5684-430: The corresponding supply voltage, modelling an AND. When a path consists of two transistors in parallel, either one or both of the transistors must have low resistance to connect the supply voltage to the output, modelling an OR. Shown on the right is a circuit diagram of a NAND gate in CMOS logic. If both of the A and B inputs are high, then both the NMOS transistors (bottom half of the diagram) will conduct, neither of
5782-484: The criminal Dominic Greene. In the 2008 film The Day the Earth Stood Still , Microsoft's Surface was used. The television series NCIS: Los Angeles , which premiered 2009, makes use of multi-touch surfaces and wall panels as an initiative to go digital. In a 2008, an episode of the television series The Simpsons , Lisa Simpson travels to the underwater headquarters of Mapple to visit Steve Mobbs, who
5880-433: The development of a cost-effective 90 nm CMOS process. Toshiba and Sony developed a 65 nm CMOS process in 2002, and then TSMC initiated the development of 45 nm CMOS logic in 2004. The development of pitch double patterning by Gurtej Singh Sandhu at Micron Technology led to the development of 30 nm class CMOS in the 2000s. CMOS is used in most modern LSI and VLSI devices. As of 2010, CPUs with
5978-416: The development of faster computers as well as portable computers and battery-powered handheld electronics . In 1988, Davari led an IBM team that demonstrated a high-performance 250 nanometer CMOS process. Fujitsu commercialized a 700 nm CMOS process in 1987, and then Hitachi, Mitsubishi Electric , NEC and Toshiba commercialized 500 nm CMOS in 1989. In 1993, Sony commercialized
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#17328633384366076-477: The device and software. An increasing number of devices like smartphones , tablet computers , laptops or desktop computers have functions that are triggered by multi-touch gestures. Years before it was a viable consumer product, popular culture portrayed potential uses of multi-touch technology in the future, including in several installments of the Star Trek franchise. In the 1982 Disney sci-fi film Tron
6174-477: The device; M. O. Thurston, L. A. D'Asaro, and J. R. Ligenza who developed the diffusion processes, and H. K. Gummel and R. Lindner who characterized the device. There were originally two types of MOSFET logic, PMOS ( p-type MOS) and NMOS ( n-type MOS). Both types were developed by Frosch and Derrick in 1957 at Bell Labs. In 1948, Bardeen and Brattain patented the progenitor of MOSFET, an insulated-gate FET (IGFET) with an inversion layer. Bardeen's patent, and
6272-477: The display. In January 2007, multi-touch technology became mainstream with the iPhone , and in its iPhone announcement Apple even stated it "invented multi touch", however both the function and the term predate the announcement or patent requests, except for the area of capacitive mobile screens, which did not exist before Fingerworks/Apple's technology (Fingerworks filed patents in 2001–2005, subsequent multi-touch refinements were patented by Apple ). However,
6370-478: The early 1970s were PMOS processors, which initially dominated the early microprocessor industry. By the late 1970s, NMOS microprocessors had overtaken PMOS processors. CMOS microprocessors were introduced in 1975, with the Intersil 6100 , and RCA CDP 1801 . However, CMOS processors did not become dominant until the 1980s. CMOS was initially slower than NMOS logic , thus NMOS was more widely used for computers in
6468-444: The end of those resistive wires see slow input transitions. Careful design which avoids weakly driven long skinny wires reduces this effect, but crowbar power can be a substantial part of dynamic CMOS power. Parasitic transistors that are inherent in the CMOS structure may be turned on by input signals outside the normal operating range, e.g. electrostatic discharges or line reflections . The resulting latch-up may damage or destroy
6566-585: The extremely thin gate dielectric. Using high-κ dielectrics instead of silicon dioxide that is the conventional gate dielectric allows similar device performance, but with a thicker gate insulator, thus avoiding this current. Leakage power reduction using new material and system designs is critical to sustaining scaling of CMOS. CMOS circuits dissipate power by charging the various load capacitances (mostly gate and wire capacitance, but also drain and some source capacitances) whenever they are switched. In one complete cycle of CMOS logic, current flows from V DD to
6664-411: The family of processes used to implement that circuitry on integrated circuits (chips). CMOS circuitry dissipates less power than logic families with resistive loads. Since this advantage has increased and grown more important, CMOS processes and variants have come to dominate, thus the vast majority of modern integrated circuit manufacturing is on CMOS processes. CMOS logic consumes around one seventh
6762-476: The first generation Magic Trackpad lauded its design but criticized its price. Scott Stein of CNET wrote, "Apple's $ 69 Bluetooth device is minimalist and not particularly cheap"; "We're not sure we'd ditch our mouse and use the Magic Trackpad, but it's a compact solution for the touch-addicted." Macworld also praised the trackpad's design similarity with the Apple Wireless Keyboard: "The Magic Trackpad
6860-454: The first touch screens in the late 1960s. In 1972, Control Data released the PLATO IV computer, an infrared terminal used for educational purposes, which employed single-touch points in a 16×16 array user interface. These early touchscreens only registered one point of touch at a time. On-screen keyboards (a well-known feature today) were thus awkward to use, because key-rollover and holding down
6958-540: The iGesture Pad. in the early 2000s Alan Hedge , professor of human factors and ergonomics at Cornell University published several studies about this technology. In 2005, Apple acquired Fingerworks and its multi-touch technology. In 2004, French start-up JazzMutant developed the Lemur Input Device , a music controller that became in 2005 the first commercial product to feature a proprietary transparent multi-touch screen, allowing direct, ten-finger manipulation on
7056-528: The implementation of multi-touch in user interfaces, however the legitimacy of some patents has been disputed. Apple additionally attempted to register "Multi-touch" as a trademark in the United States—however its request was denied by the United States Patent and Trademark Office because it considered the term generic . Multi-touch sensing and processing occurs via an ASIC sensor that
7154-522: The input. The transistors' resistances are never exactly equal to zero or infinity, so Q will never exactly equal Vss or Vdd, but Q will always be closer to Vss than A was to Vdd (or vice versa if A were close to Vss). Without this amplification, there would be a very low limit to the number of logic gates that could be chained together in series, and CMOS logic with billions of transistors would be impossible. The power supply pins for CMOS are called V DD and V SS , or V CC and Ground(GND) depending on
7252-425: The load capacitance to charge it and then flows from the charged load capacitance (C L ) to ground during discharge. Therefore, in one complete charge/discharge cycle, a total of Q=C L V DD is thus transferred from V DD to ground. Multiply by the switching frequency on the load capacitances to get the current used, and multiply by the average voltage again to get the characteristic switching power dissipated by
7350-444: The logic based on De Morgan's laws , the PMOS transistors in parallel have corresponding NMOS transistors in series while the PMOS transistors in series have corresponding NMOS transistors in parallel. More complex logic functions such as those involving AND and OR gates require manipulating the paths between gates to represent the logic. When a path consists of two transistors in series, both transistors must have low resistance to
7448-408: The manufacturer. V DD and V SS are carryovers from conventional MOS circuits and stand for the drain and source supplies. These do not apply directly to CMOS, since both supplies are really source supplies. V CC and Ground are carryovers from TTL logic and that nomenclature has been retained with the introduction of the 54C/74C line of CMOS. An important characteristic of a CMOS circuit
7546-401: The outputs of the PMOS and NMOS transistors are complementary such that when the input is low, the output is high, and when the input is high, the output is low. No matter what the input is, the output is never left floating (charge is never stored due to wire capacitance and lack of electrical drain/ground). Because of this behavior of input and output, the CMOS circuit's output is the inverse of
7644-403: The person was pressing on the glass), the system was somewhat pressure-sensitive as well. Of note, this system was input only and not able to display graphics. In 1983, Bell Labs at Murray Hill published a comprehensive discussion of touch-screen based interfaces, though it makes no mention of multiple fingers. In the same year, the video-based Video Place/Video Desk system of Myron Krueger
7742-583: The power consumption per unit area of the chip has risen tremendously. Broadly classifying, power dissipation in CMOS circuits occurs because of two components, static and dynamic: Both NMOS and PMOS transistors have a gate–source threshold voltage (V th ), below which the current (called sub threshold current) through the device will drop exponentially. Historically, CMOS circuits operated at supply voltages much larger than their threshold voltages (V dd might have been 5 V, and V th for both NMOS and PMOS might have been 700 mV). A special type of
7840-479: The power of NMOS logic , and about 10 million times less power than bipolar transistor-transistor logic (TTL). CMOS circuits use a combination of p-type and n-type metal–oxide–semiconductor field-effect transistor (MOSFETs) to implement logic gates and other digital circuits. Although CMOS logic can be implemented with discrete devices for demonstrations, commercial CMOS products are integrated circuits composed of up to billions of transistors of both types, on
7938-512: The process diagram below right) The contacts penetrate an insulating layer between the base layers and the first layer of metal (metal1) making a connection. The inputs to the NAND (illustrated in green color) are in polysilicon. The transistors (devices) are formed by the intersection of the polysilicon and diffusion; N diffusion for the N device & P diffusion for the P device (illustrated in salmon and yellow coloring respectively). The output ("out")
8036-415: The quick developments in this field, and many companies using the term to market older technology which is called gesture-enhanced single-touch or several other terms by other companies and researchers. Several other similar or related terms attempt to differentiate between whether a device can exactly determine or only approximate the location of different points of contact to further differentiate between
8134-479: The rise of the Japanese semiconductor industry. Toshiba developed C MOS (Clocked CMOS), a circuit technology with lower power consumption and faster operating speed than ordinary CMOS, in 1969. Toshiba used its C MOS technology to develop a large-scale integration (LSI) chip for Sharp 's Elsi Mini LED pocket calculator , developed in 1971 and released in 1972. Suwa Seikosha (now Seiko Epson ) began developing
8232-405: The screen to activate a switch (or a U-shaped gesture for a toggle switch), and touchscreen keyboards (including a study that showed that users could type at 25 words per minute for a touchscreen keyboard compared with 58 words per minute for a standard keyboard, with multi-touch hypothesized to improve data entry rate); multi-touch gestures such as selecting a range of a line, connecting objects, and
8330-463: The software side of multi-touch input systems. A 1982 system at the University of Toronto used a frosted-glass panel with a camera placed behind the glass. When a finger or several fingers pressed on the glass, the camera would detect the action as one or more black spots on an otherwise white background, allowing it to be registered as an input. Since the size of a dot was dependent on pressure (how hard
8428-632: The standard name for the technology by the early 1970s. CMOS overtook NMOS logic as the dominant MOSFET fabrication process for very large-scale integration (VLSI) chips in the 1980s, also replacing earlier transistor–transistor logic (TTL) technology. CMOS has since remained the standard fabrication process for MOSFET semiconductor devices in VLSI chips. As of 2011 , 99% of IC chips, including most digital , analog and mixed-signal ICs, were fabricated using CMOS technology. Two important characteristics of CMOS devices are high noise immunity and low static power consumption . Since one transistor of
8526-440: The term resulted from the quick developments in this field, and many companies using the term to market older technology which is called gesture-enhanced single-touch or several other terms by other companies and researchers. Several other similar or related terms attempt to differentiate between whether a device can exactly determine or only approximate the location of different points of contact to further differentiate between
8624-434: The transistor is on, because there is a current path from V dd to V ss through the load resistor and the n-type network. Static CMOS gates are very power efficient because they dissipate nearly zero power when idle. Earlier, the power consumption of CMOS devices was not the major concern while designing chips. Factors like speed and area dominated the design parameters. As the CMOS technology moved below sub-micron levels
8722-659: The transistor used in some CMOS circuits is the native transistor , with near zero threshold voltage . SiO 2 is a good insulator, but at very small thickness levels electrons can tunnel across the very thin insulation; the probability drops off exponentially with oxide thickness. Tunnelling current becomes very important for transistors below 130 nm technology with gate oxides of 20 Å or thinner. Small reverse leakage currents are formed due to formation of reverse bias between diffusion regions and wells (for e.g., p-type diffusion vs. n-well), wells and substrate (for e.g., n-well vs. p-substrate). In modern process diode leakage
8820-478: The user's touch and their electronic devices and became commercial on May 29, 2007. Similarly, in 2001, Mitsubishi Electric Research Laboratories (MERL) began development of a multi-touch, multi-user system called DiamondTouch . In 2008, the Diamondtouch became a commercial product and is also based on capacitance, but able to differentiate between multiple simultaneous users or rather, the chairs in which each user
8918-415: The various technological capabilities, but they are often used as synonyms in marketing. The use of touchscreen technology predates both multi-touch technology and the personal computer. Early synthesizer and electronic instrument builders like Hugh Le Caine and Robert Moog experimented with using touch-sensitive capacitance sensors to control the sounds made by their instruments. IBM began building
9016-495: The various technological capabilities, but they are often used as synonyms in marketing. Multi-touch is commonly implemented using capacitive sensing technology in mobile devices and smart devices . A capacitive touchscreen typically consists of a capacitive touch sensor , application-specific integrated circuit (ASIC) controller and digital signal processor (DSP) fabricated from CMOS (complementary metal–oxide–semiconductor ) technology. A more recent alternative approach
9114-413: The wafer. J.R. Ligenza and W.G. Spitzer studied the mechanism of thermally grown oxides and fabricated a high quality Si/ SiO 2 stack in 1960. Following this research, Mohamed Atalla and Dawon Kahng proposed a silicon MOS transistor in 1959 and successfully demonstrated a working MOS device with their Bell Labs team in 1960. Their team included E. E. LaBate and E. I. Povilonis who fabricated
9212-442: Was familiar with work done by Weimer at RCA. In 1955, Carl Frosch and Lincoln Derick accidentally grew a layer of silicon dioxide over the silicon wafer, for which they observed surface passivation effects. By 1957 Frosch and Derrick, using masking and predeposition, were able to manufacture silicon dioxide transistors and showed that silicon dioxide insulated, protected silicon wafers and prevented dopants from diffusing into
9310-408: Was influential in development of multi-touch gestures such as pinch-to-zoom, though this system had no touch interaction itself. By 1984, both Bell Labs and Carnegie Mellon University had working multi-touch-screen prototypes – both input and graphics – that could respond interactively in response to multiple finger inputs. The Bell Labs system was based on capacitive coupling of fingers, whereas
9408-489: Was once used but now the material is polysilicon . Other metal gates have made a comeback with the advent of high-κ dielectric materials in the CMOS process, as announced by IBM and Intel for the 45 nanometer node and smaller sizes. The principle of complementary symmetry was first introduced by George Sziklai in 1953 who then discussed several complementary bipolar circuits. Paul Weimer , also at RCA , invented in 1962 thin-film transistor (TFT) complementary circuits,
9506-488: Was outlined, on the basis of thermal oxidation of a silicon substrate to yield a layer of silicon dioxide located between the drain contact and the source contact. CMOS was commercialised by RCA in the late 1960s. RCA adopted CMOS for the design of integrated circuits (ICs), developing CMOS circuits for an Air Force computer in 1965 and then a 288- bit CMOS SRAM memory chip in 1968. RCA also used CMOS for its 4000-series integrated circuits in 1968, starting with
9604-409: Was released on July 27, 2010. It is made of glass and aluminum in the same style as Apple's Wireless Keyboard and sits flush with it. The entire trackpad can be used as a button, pressing down on the trackpad puts pressure on two circular feet below to register a click. The trackpad connects via Bluetooth and is powered by two AA batteries. The second generation Magic Trackpad, initially marketed as
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