228:
216:
38:
1038:
2421:
352:). The sensor is covered with a sheet of glass or clear plastic, which is topped with the LED die. The LED beam fires downward. To minimize losses of light, the useful absorption spectrum of the sensor must match the output spectrum of the LED, which almost invariably lies in the near infrared. The optical channel is made as thin as possible for a desired
1135:
972:(FETs) as sensors are rare and, like vactrols, can be used as remote-controlled analog potentiometers provided that the voltage across the FET's output terminal does not exceed a few hundred mV. Opto-FETs turn on without injecting switching charge in the output circuit, which is particularly useful in
870:
A novel idea of a particular optical analog signal isolator was submitted on 3, June 2011. The proposed configuration consist of two different parts. One of them transfers the signal, and the other establishes a negative feedback to ensure that the output signal has the same features as the input
799:
by charging its terminals to a voltage of up to 0.7 V. The rate of charge is proportional to the intensity of incoming light. The energy is harvested by draining the charge through an external high-impedance path; the ratio of current transfer can reach 0.2%. This mode of operation is called
984:
All opto-isolators described so far are uni-directional. Optical channel always works one way, from the source (LED) to the sensor. The sensors, be they photoresistors, photodiodes or phototransistors, cannot emit light. But LEDs, like all semiconductor diodes, are capable of detecting incoming
120:
The value of optically coupling a solid state light emitter to a semiconductor detector for the purpose of electrical isolation was recognized in 1963 by
Akmenkalns, et al. (US patent 3,417,249). Photoresistor-based opto-isolators were introduced in 1968. They are the slowest, but also the most
790:
as sensors. When the photodiode is reverse-biased with an external voltage source, incoming light increases the reverse current flowing through the diode. The diode itself does not generate energy; it modulates the flow of energy from an external source. This mode of operation is called
629:(CdSe) photoresistors (also called light-dependent resistors, LDRs) as receivers. In applications where control linearity was not important, or where available current was too low for driving an incandescent bulb (as was the case in vacuum tube amplifiers), it was replaced with a
683:. Uniquely among photosensors, photoresistors are non-polar devices suited for either AC or DC circuits. Their resistance drops in reverse proportion to the intensity of incoming light, from virtually infinity to a residual floor that may be as low as less than a hundred
364:
ASSR-300 series is only 0.08 mm thick. Breakdown voltages of planar assemblies depend on the thickness of the transparent sheet and the configuration of bonding wires that connect the dies with external pins. Real in-circuit isolation voltage is further reduced by
779:
129:, and by the end of the 1970s the industry developed all principal types of opto-isolators. The majority of opto-isolators on the market use bipolar silicon phototransistor sensors. They attain medium data transfer speed, sufficient for applications like
259:, one thousand times more than the voltage limits of many electronic components. A circuit can also incorporate high voltages by design, in which case it needs safe, reliable means of interfacing its high-voltage components with low-voltage ones.
815:
range; overall system speed is limited by delays in LED output and in biasing circuitry. To minimize these delays, fast digital opto-isolators contain their own LED drivers and output amplifiers optimized for speed. These devices are called
262:
The main function of an opto-isolator is to block such high voltages and voltage transients, so that a surge in one part of the system will not disrupt or destroy the other parts. Historically, this function was delegated to
928:
Design with transistor opto-isolators requires generous allowances for wide fluctuations of parameters found in commercially available devices. Such fluctuations may be destructive, for example, when an opto-isolator in the
380:. Here, the LED and sensor dies are placed on the opposite sides of the package; the LED fires into the sensor horizontally. The LED, the sensor and the gap between them are encapsulated in a blob, or dome, of transparent
2174:
1368:"Even the garden variety signal diodes you use in circuits have a small photovoltaic effect. There are amusing stories of bizarre circuit behavior finally traced to this." - Horowitz and Hill McCoulny, p. 184.
871:
signal. This proposed analog isolator is linear over a wide range of input voltage and frequency. However linear opto couplers using this principle have been available for many years, for example the IL300.
314:
channel, captures light on the output side and transforms it back into electric signal. Unlike transformers, which pass energy in both directions with very low losses, opto-isolators are unidirectional (see
985:
light, which makes possible construction of a two-way opto-isolator from a pair of LEDs. The simplest bidirectional opto-isolator is merely a pair of LEDs placed face to face and held together with
1270:
Current through the photoresistor (output current) is proportional to the voltage applied across it. In theory it can exceed 100% of input current, but in practice dissipation of heat according to
1304:. Retrieved November 5, 2010). The same trademark, registered in 1993 for "medico-surgical tubing connector sold as a component of suction catheters" is now live and owned by Mallinckrodt Inc. (
668:(LEDs) in 1968–1970, the manufacturers replaced incandescent and neon lamps with LEDs and achieved response times of 5 milliseconds and modulation frequencies up to 250 Hz. The name
292:
344:
The physical layout of an opto-isolator depends primarily on the desired isolation voltage. Devices rated for less than a few kV have planar (or sandwich) construction. The sensor
1014:
LEDs are the preferred choice for bidirectional devices. Bidirectional opto-isolators built around pairs of GaAs:Si LEDs have current transfer ratio of around 0.06% in either
1164:
configuration. This configuration refers to optocouplers that contain a source that emits light and a sensor that only detects light when it has reflected off an object. The
1321:(Edgerton, Germeshausen, and Grier, Inc.), a defense contractor, in 1983. In 1999 EG&G purchased formerly independent PerkinElmer, and changed own name PerkinElmer (see
905:
Phototransistors are inherently slower than photodiodes. The earliest and the slowest but still common 4N35 opto-isolator, for example, has rise and fall times of 5
1218:
Based on conceptual drawings published by Basso and by Mims, p. 100. Real-world LEDs and sensors are much smaller; see the photograph in Avago, p. 3 for an example.
373:
and the surface of the package. Safe design rules require a minimal clearance of 25 mm/kV for bare metal conductors or 8.3 mm/kV for coated conductors.
1153:
configuration. This configuration refers to optocouplers with an open slot between the source and sensor that has the ability to influence incoming signals. The
41:
Schematic diagram of an opto-isolator showing source of light (LED) on the left, dielectric barrier in the center, and sensor (phototransistor) on the right
957:
observed that current transfer ratio in a batch of 4N28's can vary from 15% to more than 100%; the datasheet specified only a minimum of 10%. Transistor
303:
Component
Acceptance Notice #5, etc. Opto-isolator specifications published by manufacturers always follow at least one of these regulatory frameworks.
925:
and loaded to achieve their maximum speeds, for example, the 4N28 operates at up to 50 kHz with optimum bias and less than 4 kHz without it.
2030:
2021:
1297:
288:
392:
designs the space between the silicone blob ("inner mold") and the outer shell ("outer mold") is filled with dark dielectric compound with a matched
1248:
The input side circuitry and the LED must be matched, the output side and the sensor must be matched, but there is, usually, no need to match input
1790:
867:
of the amplifier, which maintains overall current transfer ratio at a constant level regardless of the non-linearity in the second (output) diode.
1283:
Low-cost solid-state relays have switching times of tens of milliseconds. Modern high-speed solid-state relays like Avago ASSR-300 series (see
723:
325:. Typical opto-isolators can only modulate the flow of energy already present on the output side. Unlike transformers, opto-isolators can pass
191:. Since LEDs can sense light in addition to emitting it, construction of symmetrical, bidirectional opto-isolators is possible. An optocoupled
125:
isolators and still retain a niche market in the audio and music industries. Commercialization of LED technology in 1968–1970 caused a boom in
953:
typically list only worst-case values for critical parameters; actual devices surpass these worst-case estimates in an unpredictable fashion.
1146:
configuration. This configuration refers to optocouplers enclosed in a dark container wherein the source and sensor are facing each other.
918:
730:; after 1964 one of these tubes was replaced by an optocoupler made of a LDR and a neon lamp. To date, Vactrols activated by pressing the
388:, retaining all stray light and reflecting it onto the surface of the sensor, minimizing losses in a relatively long optical channel. In
2264:
2195:
73:
from affecting the system receiving the signal. Commercially available opto-isolators withstand input-to-output voltages up to 10
738:
guitar community to "roll their own" resistive opto-isolators. Guitarists to date prefer opto-isolated effects because their superior
2406:
2377:
2347:
2330:
2301:
2253:
2233:
2187:
2166:
2140:
2116:
2099:
2082:
2065:
2048:
2013:
1984:
1854:
1121:
588:
1261:
See
Horowitz and Hill, p. 597, for an expanded list of opto-isolator types with their schematic symbols and typical specifications.
2360:
824:
6N137/HPCL2601 family of devices equipped with internal output amplifiers was introduced in the late 1970s and attained 10
283:
the human user operating this equipment. They contain a single physical isolation barrier, but provide protection equivalent to
2456:
2446:
1059:
1055:
881:
switches usually employ a photodiode opto-isolator to drive the switch. The gate of a MOSFET requires relatively small total
695:
for telephone networks. The photoresistors easily withstood voltages up to 400 volts, which made them ideal for driving
300:
1102:
156:(LED), that converts electrical input signal into light, a closed optical channel (also called dielectrical channel), and a
2175:
A 2.5kV Isolation 35kV/us CMR 250 Mbps 0.13mA/Mbps
Digital Isolator in Standard CMOS with an On-Chip Small Transformer
1996:
Safety
Considerations When Using Optocouplers and Alternative Isolators for Providing Protection Against Electrical Hazards
2451:
2148:
1074:
962:
2388:
541:
255:, switching pulses (spikes) and perturbations in power supply. Remote lightning strikes can induce surges up to 10
252:
184:
885:
to turn on and its leakage current in steady state is very low. A photodiode in photovoltaic mode can generate turn-on
958:
101:
1081:
711:. Most of these applications are now obsolete, but resistive opto-isolators retained a niche in audio, in particular
718:
American guitar and organ manufacturers of the 1960s embraced the resistive opto-isolator as a convenient and cheap
2179:
1486:
1356:
1011:
696:
897:. To reach the required threshold, solid-state relays contain stacks of up to thirty photodiodes wired in series.
275:
input and output sides. Transformers and opto-isolators are the only two classes of electronic devices that offer
2425:
796:
692:
334:
296:
1879:
Horowitz and Hill, p. 596. Ball p. 68, provides rise and fall time of 10 μs but does not specify load impedance.
1808:
2441:
1088:
345:
356:. For example, to be rated for short-term voltages of 3.75 kV and transients of 1 kV/μs, the clear
1048:
969:
751:
618:
608:
429:
248:
1168:
configuration is suitable for the development of tachometers, movement detectors and reflectance monitors.
909:
into a 100 Ohm load and its bandwidth is limited at around 10 kilohertz - sufficient for applications like
243:
Electronic equipment and signal and power transmission lines can be subjected to voltage surges induced by
2383:
2131:
1070:
914:
910:
852:
708:
688:
366:
200:
130:
921:
specification allow digital data transfer speeds of tens of kiloBauds. Phototransistors must be properly
860:
638:
521:
370:
264:
1305:
1301:
287:. Safety, testing and approval of opto-couplers are regulated by national and international standards:
1835:
2275:
1803:
1271:
1177:
1022:
mode — less than photodiode-based isolators, but sufficiently practical for real-world applications.
848:
829:
739:
665:
471:
349:
220:
153:
85:
62:
755:
2312:
1209:
Real-world schematic diagrams omit the barrier symbol, and use a single set of directional arrows.
227:
219:
Planar (top) and silicone dome (bottom) layouts – cross-section through a standard
2213:
1990:
1961:
Photodiode opto-isolators have current transfer ratios of up to 0.2% - Mataré, p. 177, table 5.1.
1777:
1575:
1343:
1190:
986:
934:
874:
828:
data transfer speeds. It remained an industry standard until the introduction of the 50 MBd
672:
was carried over on LED-based devices which are, as of 2010, still produced in small quantities.
361:
330:
272:
268:
195:
contains a photodiode opto-isolator which drives a power switch, usually a complementary pair of
2196:
Analog
Devices Introduces Digital Isolator with Integrated Transformer Driver and PWM Controller
1157:
configuration is suitable for object detection, vibration detection, and bounce-free switching.
207:
of light by external objects obstructing the path of light or reflecting light into the sensor.
333:
between input and output sides. Both transformers and opto-isolators are effective in breaking
215:
34:
Insulates two circuits from one another while allowing signals to pass through in one direction
2402:
2373:
2343:
2326:
2297:
2249:
2229:
2219:
2183:
2162:
2136:
2112:
2095:
2078:
2061:
2044:
2009:
1980:
1342:
The former semiconductor division of
Agilent Technologies operates as an independent company,
938:
894:
573:
393:
353:
284:
192:
109:
2321:
2261:
2224:
795:. Alternatively, in the absence of external bias the diode converts the energy of light into
1322:
1007:
1003:
996:
837:
712:
626:
465:
438:
168:
28:
1677:
of illumination the response times are typically in the range of 5 ms to 100 ms."
1095:
734:
are ubiquitous in the music industry. Shortages of genuine PerkinElmer
Vactrols forced the
2268:
1858:
973:
882:
821:
653:
622:
508:
434:
321:
180:
126:
89:
1850:
1809:
Agilent HCPL-7723 & HCPL-0723 50 MBd 2 ns PWD High Speed CMOS Optocoupler (Datasheet)
1300:, trademark registered in 1969 for "photocell combined with a light source" is now dead (
766:
compounds. Such fluctuations take hours to settle and can be only partially offset with
2200:
1743:
PerkinElmer, pp. 35–36; Silonex, p. 1 (see also distortion charts on subsequent pages).
735:
348:
is mounted directly on the lead frame of its package (usually, a six-pin or a four-pin
337:, common in industrial and stage equipment, caused by high or noisy return currents in
326:
941:
and causes spurious oscillations, or when unexpected delays in opto-isolators cause a
2435:
2126:
2122:
1770:
Porat and Barna, p. 464. See also full specifications of currently produced devices:
1326:
1232:
990:
942:
930:
863:
to compensate for diode non-linearity. One of two identical diodes is wired into the
843:
Photodiode opto-isolators can be used for interfacing analog signals, although their
759:
676:
441:
232:
172:
157:
105:
820:: their LEDs and sensors are fully encapsulated within a digital logic circuit. The
310:
by input current. It transforms useful input signal into light, sends it across the
2355:
2239:
1438:
See
Ananthi, pp. 56, 62 for a practical example of an opto-coupled EEG application.
731:
727:
680:
649:
203:
contains a source of light and a sensor, but its optical channel is open, allowing
70:
37:
2025:. Energy Efficiency and Technology, September 1, 2009. Retrieved November 2, 2010.
1899:
MIDI Electrical
Specification Diagram & Proper Design of Joystick/MIDI Adapter
778:
108:
pairs. Usually opto-isolators transfer digital (on-off) signals and can act as an
92:
in the same opaque package. Other types of source-sensor combinations include LED-
2397:
2368:
2338:
2292:
2244:
2209:
Building a Safe and Robust Industrial System with Avago Technologies Optocouplers
2157:
2107:
2090:
2073:
2056:
2039:
2004:
1975:
1836:
A Novel Approach to Analog Signal Isolation through Digital Opto-coupler (YOUTAB)
754:. Performance is further compromised by slow fluctuations of resistance owing to
2307:
1898:
1674:
1138:
A reflective pair (left) and two slotted couplers with the light paths in purple
1037:
906:
700:
675:
Photoresistors used in opto-isolators rely on bulk effects in a uniform film of
642:
338:
78:
27:
This article is about the electronic component. For the optical component, see
1019:
1015:
812:
801:
792:
787:
747:
743:
704:
488:
311:
307:
236:
204:
176:
165:
138:
93:
2206:
Jeremy Seah Eng Lee, Alexander Jaus, Patrick Sullivan, Chua Teck Bee (2005).
2287:
2208:
1995:
1772:
1580:
1284:
954:
950:
808:
657:
630:
455:
357:
244:
134:
97:
17:
961:
in the same batch can vary from 300 to 3000, resulting in 10:1 variance in
376:
Opto-isolators rated for 2.5 to 6 kV employ a different layout called
2420:
1227:
A transformer can have as many coils as necessary. Each coil can act as a
840:, which require two independent external power supplies of 5 V each.
1000:
946:
864:
767:
648:
The turn-on and turn-off lag of an incandescent bulb lies in hundreds of
468:
381:
150:
2280:
1318:
922:
763:
719:
149:
An opto-isolator contains a source (emitter) of light, almost always a
1134:
832:
7723/0723 family in 2002. The 7723/0723 series opto-isolators contain
306:
An opto-isolator connects input and output sides with a beam of light
878:
811:
in photoconductive mode. The response times of PIN diodes lie in the
782:
A fast photodiode opto-isolator with an output-side amplifier circuit
584:
385:
196:
161:
122:
69:
between two isolated circuits by using light. Opto-isolators prevent
66:
687:. These properties made the original Vactrol a convenient and cheap
2040:
Practical electrical equipment and installations in hazardous areas
2031:
MEMs-Based Magnetic Coils Exceed The Limitation Of Optical Couplers
1902:. MIDI Manufacturers Association. 1985. Retrieved November 2, 2010.
2228:. Advances in electronics and electron physics, Volume 45 (1978),
2172:
S. Kaeriyama, S. Uchida, M. Furumiya, M. Okada, M. Mizuno (2010).
1133:
844:
777:
750:
signal is higher than that of a professional electrically-coupled
661:
633:. These devices (or just their LDR component) were commonly named
560:
226:
214:
188:
36:
786:
Diode opto-isolators employ LEDs as sources of light and silicon
637:, after a trademark of Vactec, Inc. The trademark has since been
223:. Relative sizes of LED (red) and sensor (green) are exaggerated.
112:, but some techniques allow them to be used with analog signals.
989:. If necessary, the gap between two LEDs can be extended with a
917:. Devices like PC-900 or 6N138 recommended in the original 1983
833:
825:
742:
results in "inherently high quality of the sound". However, the
256:
74:
2225:
Light-Emitting Devices, Part II: Device Design and Applications
2034:. Electronic Design, July 24, 2000. Retrieved November 4, 2010.
1791:
Agilent Technologies Introduces Industry's Fastest Optocouplers
1936:
Ball, pp. 181–182. Shorting one side of an H-bridge is called
1031:
684:
660:
but limits the practical modulation frequency range to a few
160:, which detects incoming light and either generates electric
641:, but the original Vactrols are still being manufactured by
2037:
Geoffrey Bottrill, Derek Cheyne, G. Vijayaraghavan (2005).
1171:
The later two configurations are frequently referred to as
171:
flowing from an external power supply. The sensor can be a
2272:. Sensor Magazine. March 2002. Retrieved November 4, 2010.
1287:) attain switching times of less than 70 nanoseconds.
2313:
Photoconductive Cells and Analog Optoisolators (Vactrols)
2152:. Power Electronics Technology, May 2005, pp. 48–52.
851:. A special class of analog opto-isolators introduced by
1686:
Weber, p. 190; PerkinElmer, pp. 2,7,28; Collins, p. 181.
2057:
Handmade Electronic Music: The Art of Hardware Hacking
1851:
http://www.vishay.com/optocouplers/list/product-83622/
2005:
Analog interfacing to embedded microprocessor systems
1713:
Fliegler and Eiche, p. 28; Teagle and Sprung, p. 225.
999:
LEDs have relatively poor transfer efficiency, thus
613:
The earliest opto-isolators, originally marketed as
77:
and voltage transients with speeds up to 25 kV/
2158:
Grounds for Grounding: A Circuit to System Handbook
1655:
Weber, p. 190; PerkinElmer, p. 28; Collins, p. 181.
1062:. Unsourced material may be challenged and removed.
1848:Vishay website, IL300 data (accessed 10-20-2015),
1485:See Basso for a discussion of such interfacing in
707:, professional light measurement instruments and
316:
2149:Navigating the Regulatory Maze with Optocouplers
1325:). An unrelated company, Silonex (a division of
617:, emerged in the 1960s. They employed miniature
2356:Audio level control with resistive optocouplers
2203:. October 21, 2010. Retrieved November 3, 2010.
1359:photodiodes can generate light. - Mims, p. 102.
84:A common type of opto-isolator consists of an
2108:Overvoltage protection of low voltage systems
8:
1306:USPTO database record serial number 74381130
1302:USPTO database record serial number 72318344
1274:limits current transfer ratio at below 100%.
2392:. June 4, 2008. Retrieved November 5, 2010.
2281:Application Bulletin AB-7. GMR in Isolation
1999:. January 2010. Retrieved November 5, 2010.
1833:Modern Applied Science Vol 5, No 3 (2011).
1329:) brands its photoresistive opto-isolators
1752:PerkinElmer, pp. 7, 29, 38; Silonex, p. 8.
889:in a reasonably short time but its output
329:or slow-moving signals and do not require
2284:. March 2007. Retrieved November 4, 2010.
1780:. March 2010. Retrieved November 2, 2010.
1298:United States Patent and Trademark Office
1122:Learn how and when to remove this message
699:. Other industrial applications included
652:range, which makes the bulb an effective
2398:Tube Amp Talk for the Guitarist and Tech
1820:
1818:
1605:
1603:
1601:
1599:
1497:
1495:
403:
2389:Application Note 56. Solid State Relays
2262:Magnetic Couplers in Industrial Systems
2071:Ritchie Fliegler, Jon F. Eiche (1993).
1948:
1946:
1730:
1728:
1553:
1551:
1549:
1530:
1528:
1380:
1239:– picking up energy stored in the core.
1202:
740:separation of audio and control grounds
2074:Amps!: the other half of rock 'n' roll
1923:
1921:
1919:
1917:
1543:Joffe and Kai-Sang Lock, pp. 268, 276.
1509:
1507:
1454:
1452:
1450:
1448:
1446:
1444:
2155:Elya B. Joffe, Kai-Sang Lock (2010).
2022:Dealing with Low-Current Optocouplers
1700:
1698:
1696:
1694:
1692:
1633:
1631:
1629:
1627:
1617:
1615:
1434:
1432:
893:is many times less than the MOSFET's
7:
1395:
1393:
1060:adding citations to reliable sources
919:Musical Instrument Digital Interface
1581:ASSR-301C and ASSR-302C (datasheet)
235:. Note the pair of class Y1 safety
2369:Fender Amps: The First Fifty Years
2322:Introduction to digital techniques
2319:Dan I. Porat, Arpad Barna (1979).
1976:A text book of medical instruments
1794:. Business Wire. December 2, 2002.
1355:Exception: Ternary and quaternary
807:The fastest opto-isolators employ
726:'s early tremolo effects used two
279:— they protect both the equipment
25:
2366:John Teagle, John Sprung (1995).
2245:Mims Circuit Scrapbook (volume 2)
1426:Graf, p. 522; PerkinElmer, p. 28.
746:introduced by a photoresistor at
133:. The fastest opto-isolators use
2419:
2091:Modern dictionary of electronics
1534:Joffe and Kai-Sang Lock, p. 277.
1417:Joffe and Kai-Sang Lock, p. 279.
1036:
394:coefficient of thermal expansion
2293:Troubleshooting Analog Circuits
1761:Horowitz and Hill, pp. 596–597.
1231:, pumping energy into a common
1047:needs additional citations for
2363:). Retrieved November 2, 2010.
2342:. Cambridge University Press.
2182:. Honolulu, June 16–18, 2010.
2135:. Cambridge University Press.
1308:. Retrieved November 5, 2010).
901:Phototransistor opto-isolators
859:photodiodes and an input-side
1:
2316:. Retrieved November 2, 2010.
2216:. Retrieved November 2, 2010.
1812:. Retrieved November 2, 2010.
1584:. Retrieved November 3, 2010.
1142:Usually, optocouplers have a
253:radio frequency transmissions
1673:PerkinElmer, pp. 6–7: "at 1
1487:switched-mode power supplies
980:Bidirectional opto-isolators
752:voltage-controlled amplifier
581:Stack of photodiodes driving
578:Stack of GaAs infrared LEDs
542:Silicon-controlled rectifier
185:silicon-controlled rectifier
2401:. Hal Leonard Corporation.
2372:. Hal Leonard Corporation.
2077:. Hal Leonard Corporation.
1773:6N137 / HCPL-2601 datasheet
1155:slotted coupler/interrupter
1151:slotted coupler/interrupter
697:vacuum fluorescent displays
664:. With the introduction of
319:) and they cannot transmit
2473:
2180:Symposium on VLSI Circuits
1824:Horowitz and Hill, p. 598.
1637:Mataré, p. 177, table 5.1.
1501:Horowitz and Hill, p. 595.
606:
65:that transfers electrical
26:
2336:E. Fred Schubert (2006).
2054:Nicholas Collins (2009).
2019:Christophe Basso (2009).
1979:. New Age International.
1160:Some optocouplers have a
1149:Some optocouplers have a
915:pulse-width motor control
818:full logic opto-isolators
774:Photodiode opto-isolators
621:as sources of light, and
503:
501:Transistor opto-isolator
500:
449:
433:
423:
2060:. Taylor & Francis.
1593:Bottrill et al., p. 175.
1317:Vactec was purchased by
970:field-effect transistors
770:in the control circuit.
619:incandescent light bulbs
603:Resistive opto-isolators
2146:Alexander Jaus (2005).
2088:Rudolf F. Graf (1999).
2002:Stuart R. Ball (2004).
1026:Types of configurations
945:through one side of an
836:LED drivers and a CMOS
609:Resistive opto-isolator
430:Incandescent light bulb
424:Resistive opto-isolator
419:Current transfer ratio
400:Types of opto-isolators
249:electrostatic discharge
2193:Linda Kincaid (2010).
2132:The Art of Electronics
1139:
1001:near infrared spectrum
911:electroencephalography
783:
689:automatic gain control
596:Practically unlimited
265:isolation transformers
240:
224:
201:slotted optical switch
131:electroencephalography
42:
2457:Semiconductor devices
2447:Electrical components
2395:Gerald Weber (1997).
2384:Vishay Semiconductors
2339:Light-emitting diodes
2028:Ashok Bindra (2000).
1621:Vishay Semiconductor.
1178:photoelectric sensors
1137:
968:Opto-isolators using
861:operational amplifier
781:
666:light-emitting diodes
384:. The dome acts as a
277:reinforced protection
273:galvanically isolated
230:
218:
40:
2452:Solid state switches
2428:at Wikimedia Commons
2105:Peter Hasse (2000).
1952:Mims vol. 2, p. 102.
1804:Agilent Technologies
1331:Audiohm Optocouplers
1056:improve this article
830:Agilent Technologies
793:photoconductive mode
709:auto-exposure meters
554:Opto-isolated triac
481:Diode opto-isolator
350:dual in-line package
221:dual in-line package
154:light-emitting diode
139:photoconductive mode
63:electronic component
2259:John Myers (2002).
2190:. pp. 197–198.
1973:S. Ananthi (2006).
849:distorts the signal
838:buffered amplifiers
331:matching impedances
2267:2011-07-16 at the
2236:, pp. 40–200.
2214:Avago Technologies
1991:Avago Technologies
1857:2016-12-27 at the
1778:Avago Technologies
1664:Schubert, pp. 8–9.
1576:Avago Technologies
1344:Avago Technologies
1191:Galvanic isolation
1140:
991:glass fiber insert
987:heat-shrink tubing
935:DC-to-DC converter
875:Solid-state relays
784:
557:GaAs infrared LED
538:GaAs infrared LED
535:Opto-isolated SCR
504:GaAs infrared LED
484:GaAs infrared LED
269:inductive coupling
241:
225:
211:Electric isolation
43:
2424:Media related to
2220:Herbert F. Mataré
1704:PerkinElmer, p. 3
1399:Lee et al., p. 2.
1296:According to the
1132:
1131:
1124:
1106:
949:. Manufacturers'
939:transfer function
895:threshold voltage
802:photovoltaic mode
600:
599:
574:Solid-state relay
354:breakdown voltage
231:Optocoupler on a
193:solid-state relay
110:electronic switch
16:(Redirected from
2464:
2423:
2353:Silonex (2002).
1962:
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1734:Collins, p. 181.
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1522:Jaus, pp. 50–51.
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1323:reverse takeover
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1064:
1040:
1032:
997:Visible spectrum
713:guitar amplifier
627:cadmium selenide
524:phototransistor
507:Bipolar silicon
410:Source of light
404:
285:double isolation
169:electric current
59:optical isolator
49:(also called an
29:optical isolator
21:
2472:
2471:
2467:
2466:
2465:
2463:
2462:
2461:
2442:Optoelectronics
2432:
2431:
2416:
2288:Robert A. Pease
2276:NVE Corporation
2269:Wayback Machine
2240:Forrest M. Mims
1970:
1965:
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1199:
1187:
1166:reflective pair
1162:reflective pair
1128:
1117:
1111:
1108:
1071:"Opto-isolator"
1065:
1063:
1053:
1041:
1028:
1020:photoconductive
982:
974:sample and hold
903:
822:Hewlett-Packard
797:electric energy
776:
679:; there are no
654:low-pass filter
623:cadmium sulfide
611:
605:
582:
509:phototransistor
425:
402:
213:
181:phototransistor
147:
127:optoelectronics
118:
90:phototransistor
35:
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22:
15:
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2426:Opto-isolators
2415:
2414:External links
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2364:
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2305:
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2201:Analog Devices
2191:
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2161:. Wiley-IEEE.
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1722:Weber, p. 190.
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1646:Mataré, p. 177
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1557:Mataré, p. 174
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1408:Hasse, p. 145.
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732:stompbox pedal
607:Main article:
604:
601:
598:
597:
594:
591:
579:
576:
570:
569:
566:
565:Low to medium
563:
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546:Low to medium
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2407:0-9641060-1-9
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2378:0-7935-3733-9
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2349:
2348:0-521-86538-7
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2331:0-471-02924-6
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2188:1-4244-5454-9
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2167:0-471-66008-6
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2150:
2145:
2142:
2141:0-521-37095-7
2138:
2134:
2133:
2128:
2127:Winfield Hill
2124:
2123:Paul Horowitz
2121:
2118:
2117:0-85296-781-0
2114:
2110:
2109:
2104:
2101:
2100:0-7506-9866-7
2097:
2093:
2092:
2087:
2084:
2083:0-7935-2411-3
2080:
2076:
2075:
2070:
2067:
2066:0-415-99873-5
2063:
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2058:
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2049:0-7506-6398-7
2046:
2042:
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2027:
2024:
2023:
2018:
2015:
2014:0-7506-7723-6
2011:
2007:
2006:
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1985:81-224-1572-5
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1938:shoot-through
1933:
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1927:Pease, p. 73.
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1488:
1482:
1479:
1476:Hasse, p. 60.
1473:
1470:
1467:Hasse, p. 43.
1464:
1461:
1458:Mims, p. 100.
1455:
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1433:
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1420:
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1396:
1394:
1390:
1387:Graf, p. 522.
1384:
1381:
1375:
1365:
1362:
1358:
1352:
1349:
1346:, since 2005.
1345:
1339:
1336:
1332:
1328:
1327:Carlyle Group
1324:
1320:
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1303:
1299:
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1252:output sides.
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1234:
1233:magnetic core
1230:
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1115:
1112:December 2019
1104:
1101:
1097:
1094:
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1087:
1083:
1080:
1076:
1073: –
1072:
1068:
1067:Find sources:
1061:
1057:
1051:
1050:
1045:This article
1043:
1039:
1034:
1033:
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1025:
1023:
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979:
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960:
956:
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948:
944:
943:short circuit
940:
936:
932:
931:feedback loop
926:
924:
920:
916:
912:
908:
900:
898:
896:
892:
888:
884:
880:
877:built around
876:
872:
868:
866:
865:feedback loop
862:
858:
854:
850:
846:
845:non-linearity
841:
839:
835:
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813:subnanosecond
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761:
760:memory effect
757:
756:light history
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703:, industrial
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681:p-n junctions
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71:high voltages
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48:
47:opto-isolator
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2178:. IEEE 2010
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2008:. Elsevier.
2003:
1994:
1974:
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1932:
1911:Ball, p. 67.
1907:
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1888:Ball, p. 68.
1884:
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1870:Ball, p. 61.
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1566:Ball, p. 69.
1562:
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1513:Jaus, p. 48.
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1066:
1054:Please help
1049:verification
1046:
1029:
1016:photovoltaic
995:
983:
967:
937:changes its
927:
904:
890:
886:
873:
869:
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842:
817:
806:
785:
762:inherent in
728:vacuum tubes
717:
701:photocopiers
674:
669:
650:milliseconds
647:
634:
614:
612:
593:Low to high
413:Sensor type
407:Device type
389:
377:
375:
343:
339:ground wires
335:ground loops
320:
305:
293:EN (CENELEC)
280:
276:
267:, which use
261:
242:
148:
119:
83:
58:
55:photocoupler
54:
50:
46:
44:
18:Optoisolator
2361:PDF version
2308:PerkinElmer
1272:Joule's law
1173:optosensors
1144:closed pair
847:invariably
788:photodiodes
722:modulator.
715:, markets.
643:PerkinElmer
639:genericized
615:light cells
390:double mold
295:60747-5-2,
291:60747-5-2,
187:(SCR) or a
158:photosensor
51:optocoupler
2436:Categories
2296:. Newnes.
2248:. Newnes.
2094:. Newnes.
2043:. Newnes.
1376:References
1235:, or as a
1082:newspapers
976:circuits.
951:datasheets
853:Burr-Brown
809:PIN diodes
748:line level
744:distortion
705:automation
693:compressor
583:a pair of
568:Very high
522:Darlington
489:photodiode
426:(Vactrol)
317:exceptions
312:dielectric
237:capacitors
205:modulation
177:photodiode
135:PIN diodes
94:photodiode
2325:. Wiley.
1285:datasheet
1237:secondary
1012:AlGaAs:Si
963:bandwidth
955:Bob Pease
658:rectifier
631:neon lamp
625:(CdS) or
549:>100%
530:100–600%
496:0.1–0.2%
456:Neon lamp
450:<100%
447:Very low
386:reflector
369:over the
358:polyimide
308:modulated
245:lightning
166:modulates
145:Operation
2386:(2008).
2310:(2001).
2290:(1991).
2278:(2007).
2265:Archived
2242:(2000).
2222:(1978).
2129:(2006).
1993:(2010).
1855:Archived
1806:(2005).
1578:(2007).
1319:EG&G
1185:See also
947:H-bridge
768:feedback
635:Vactrols
493:Highest
487:Silicon
469:infrared
382:silicone
367:creepage
271:between
61:) is an
2111:. IET.
1968:Sources
1229:primary
1096:scholar
1008:GaAs:Si
891:voltage
764:cadmium
720:tremolo
670:Vactrol
585:MOSFETs
527:Medium
516:2–120%
513:Medium
197:MOSFETs
116:History
67:signals
2405:
2376:
2346:
2329:
2300:
2252:
2232:
2186:
2165:
2139:
2115:
2098:
2081:
2064:
2047:
2012:
1983:
1609:Basso.
1098:
1091:
1084:
1077:
1069:
923:biased
887:charge
883:charge
879:MOSFET
724:Fender
587:or an
444:(LDR)
416:Speed
299:1577,
162:energy
123:linear
100:, and
96:, LED-
88:and a
1357:GaAsP
1197:Notes
1103:JSTOR
1089:books
933:of a
855:uses
662:Hertz
561:TRIAC
362:Avago
322:power
189:triac
98:LASCR
57:, or
2403:ISBN
2374:ISBN
2344:ISBN
2327:ISBN
2298:ISBN
2250:ISBN
2230:ISBN
2184:ISBN
2163:ISBN
2137:ISBN
2113:ISBN
2096:ISBN
2079:ISBN
2062:ISBN
2045:ISBN
2010:ISBN
1981:ISBN
1075:news
1010:and
1004:GaAs
959:beta
834:CMOS
758:, a
691:and
685:Ohms
656:and
589:IGBT
476:Low
466:GaAs
460:Low
439:CdSe
199:. A
183:, a
179:, a
175:, a
102:lamp
2359:. (
1250:and
1175:or
1058:by
1018:or
913:or
857:two
826:MBd
736:DIY
472:LED
437:or
435:CdS
371:PCB
346:die
301:CSA
289:IEC
281:and
137:in
86:LED
45:An
2438::
2212:.
2199:.
2125:,
1945:^
1916:^
1817:^
1776:.
1727:^
1691:^
1675:fc
1626:^
1614:^
1598:^
1548:^
1527:^
1506:^
1494:^
1443:^
1431:^
1392:^
1181:.
1006:,
993:.
965:.
907:μs
804:.
645:.
396:.
341:.
327:DC
297:UL
257:kV
251:,
247:,
141:.
81:.
79:μs
75:kV
53:,
2409:.
2380:.
2350:.
2333:.
2304:.
2256:.
2169:.
2143:.
2119:.
2102:.
2085:.
2068:.
2051:.
2016:.
1987:.
1940:.
1861:.
1839:.
1489:.
1333:.
1125:)
1119:(
1114:)
1110:(
1100:·
1093:·
1086:·
1079:·
1052:.
239:.
104:-
31:.
20:)
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