1476:
242:
1521:
31:
1350:, at any one instant the clock turns on the appropriate segments of one of the digits—all the other digits are dark. The clock scans through the digits rapidly enough that it gives the illusion that it is "constantly" displaying "12:34" for an entire minute. However, each "on" segment is actually being rapidly pulsed on and off many times a second.
1466:
Most LED data sheets specify a maximum DC current that is safe for continuous operation. Often they specify some higher maximum pulsed current that is safe for brief pulses, as long as the LED controller keeps the pulse short enough and then turns off the power to the LED long enough for the LED to
317:
Miniature indicator LEDs are normally driven from low voltage DC via a current-limiting resistor. Currents of 2 mA, 10 mA and 20 mA are common. Sub-mA indicators may be made by driving ultrabright LEDs at very low current. Efficiency tends to reduce at low currents, but indicators running on 100 ÎĽA
229:
LED drivers are designed to handle fluctuation load, providing enough current to achieve the required brightness while not allowing damaging levels of current to flow. Drivers may be constant current (CC) or constant voltage (CV). In CC drivers, the voltage changes while the current stays the same.
1439:
ratings compared to standard diodes, so it may be easier than expected to enter this mode and cause damage to the LED due to overcurrent. However, the cut-in voltage is always less than the breakdown voltage, so no special reverse protections are necessary when driving an LED directly from an AC
226:, and a small voltage change may result in a large change in current. If the voltage is below or equal to the threshold no current flows and the result is an unlit LED. If the voltage is too high, the current will exceed the maximum rating, overheating and potentially destroying the LED.
1279:. In one configuration, the source voltage must be greater than or equal to the sum of the individual LED voltages; typically the LED voltages add up to around two-thirds of the supply voltage. A single current-limiting resistor may be used for each string.
105:
The simplest circuit to drive an LED is through a series resistor. It is commonly used for indicators and digital displays in many consumer appliances. However, this circuit is not energy-efficient, because energy is dissipated in the resistor as heat.
925:. The maximum continuous-on current is shown on LED datasheets, for example 20 mA (0.020A) is common for most small LEDs. Many circuits operate LEDs at less than the specified maximum current to save power, or to reduce brightness, or to use a
1266:
1254:
1312:
in order to have similar branch currents and, therefore, similar light output. Variations in the manufacturing process can make it difficult to obtain satisfactory operation when connecting some types of LEDs in parallel.
1501:
As a photodiode, an LED is sensitive to wavelengths equal to or shorter than the predominant wavelength it emits. For example, a green LED is sensitive to blue light and some green light, but not to yellow or red light.
65:
across a lit LED is approximately constant over a wide range of operating current; therefore, a small increase in applied voltage greatly increases the current. Datasheets may specify this drop as a "forward voltage"
257:
is commonly used for high power LEDs, stabilizing light output over a wide range of input voltages which might increase the useful life of batteries. Active constant current is typically regulated using a
1345:
techniques are more often used than direct drive, because they have lower net hardware costs. For example, most people who design digital clocks design them such that when the clock displays "12:34" on a
601:
479:
230:
CC drivers are used when the electrical load of the LED circuit is either unknown or fluctuates, for example, a lighting circuit where a variable number of LED lamp fixtures may be installed.
336:
or populating a PCB in a way other than its designers intended. However, the resistor value is set at the time of manufacture, removing one of the key methods of setting the LED's intensity.
929:. For indoor use, tiny surface mount high-efficiency LEDs can easily light up with 1 mA (0.001A) or more current, which most digital logic outputs can easily source or sink.
882:
174:
from the supply voltage and dividing by the desired operating current. With a sufficiently high supply voltage, multiple LEDs in series can be powered with one resistor.
973:
833:
1152:
1016:
678:
1910:
1877:
1443:
The manufacturer will normally advise how to determine the polarity of the LED in the product datasheet. However, there is no standardization of polarity markings for
1238:
1076:
919:
1310:
1179:
1043:
779:
740:
713:
368:
202:
172:
134:
91:
1432:, but they will only light on the half of the AC cycle where the LED is forward-biased. This causes the LED to turn on and off at the frequency of the AC supply.
1199:
1102:
627:
61:(LED). The circuit must provide sufficient current to light the LED at the required brightness, but must limit the current to prevent damaging the LED. The
1330:
Direct drive is the simplest-to-understand approach—it uses many independent single-LED (or single-string) circuits. For example, a person could design a
1380:
and the first LED device to use integrated circuit technology. Its development was led by Howard C. Borden and Gerald P. Pighini at HP Associates and
1459:, and the LED is stationary relative to the eye, the LED will appear to be continuously lit. Varying the on/off ratio of the pulses is known as
1759:
1455:
Many systems pulse LEDs on and off, by applying power periodically or intermittently. So long as the flicker rate is greater than the human
1704:
1645:
1634:
Application note AND8067/D: "NL27WZ04 Dual Gate
Inverter Oscillator Increases the Brightness of LEDs While Reducing Power Consumption"
1615:
1985:
1365:
their output pins means larger numbers of LEDs can be driven, without using latches. For N pins, it is possible to drive n-n LEDs.
496:
376:
835:
is the voltage drop across the switch in volts: (A) for no switch, use 0 volts, (B) for mechanical switch, use 0 volts, (C) for
1568:
2005:
1842:
1338:, the clock would turn on the appropriate segments directly and leave them on until something else needs to be displayed.
1105:
926:
634:
1540:
2010:
751:
269:(LDO) constant current regulators also allow the total LED voltage to be a higher fraction of the power supply voltage.
136:
1388:(R&D) on practical LEDs between 1962 and 1968. It was the first intelligent LED display, making it a revolution in
836:
144:
1783:
Tahan, Mohammad (Winter 2017). "Multiple String LED Driver With
Flexible and High-Performance PWM Dimming Control".
1327:
LEDs are often arranged in ways such that each LED (or each string of LEDs) can be individually turned on and off.
296:
272:
204:, then no reasonable value for the resistor can be calculated, so some other method of current limiting is used.
325:
powered keyring-type LED lights, the resistance of the cell itself is usually the only current limiting device.
233:
As an LED heats up, its voltage drop decreases (band gap decrease). This can encourage the current to increase.
2000:
1456:
1444:
1385:
93:) at a particular operating current. Very simple circuits are used for low-power indicator LEDs. More complex,
1505:
This implementation of LEDs may be added to designs with only minor modifications in circuitry. An LED can be
1463:(PWM). In some cases, PWM-based drivers are more efficient than constant current or constant voltage drivers.
1689:
1546:
1405:
295:
are typically used for switching LED drivers, which is an efficient solution to drive high-brightness LEDs.
223:
1475:
97:
circuits are required when driving high-power LEDs for illumination to achieve correct current regulation.
1460:
1904:
1871:
1347:
1335:
329:
266:
302:(IC) chips are widely used to drive the MOSFETs directly, without the need for additional circuitry.
1940:
1802:
219:
58:
1509:
in such a circuit, such that it can be used for both light emission and sensing at different times.
1429:
1409:
1342:
1964:
1818:
1792:
1607:
1526:
1369:
842:
299:
1285:
operation is also possible but can be more problematic. Parallel LEDs must have closely matched
936:
796:
1118:
1104:= (9V - 1.8V) / 5mA = (9 - 1.8) / 0.005 = 1440 ohms, then round up to a 1.5K ohm resistor (per
982:
644:
1956:
1611:
1436:
1362:
1282:
1712:
1656:
1601:
1210:
1048:
891:
1948:
1810:
1358:
265:(metal–oxide–semiconductor field-effect transistor), which is the simplest current limiter.
54:
1288:
1157:
1021:
757:
718:
691:
346:
180:
150:
112:
69:
1893:"LEDs as both Optical Sources and Detectors in Bi-directional Plastic Optical Fibre Links"
1633:
1495:
1389:
1373:
284:
280:
1944:
1806:
241:
1354:
1184:
1087:
786:
612:
276:
259:
254:
94:
1420:
is in the correct direction, a significant current flows and the device is said to be
1994:
1331:
314:
are a simple way to stabilize the LED current, but energy is wasted in the resistor.
1968:
1822:
1734:
1576:
1417:
292:
62:
1416:
will only light with the correct electrical polarity. When the voltage across the
340:
140:
1853:
1681:
1534:
1506:
1428:, very little current flows, and no light is emitted. LEDs can be operated with
1377:
1322:
39:
1892:
1520:
147:
are used to calculate the appropriate resistor value, by subtracting the LED's
1814:
1516:
1494:
detection. This capability may be used in a variety of applications including
1487:
1393:
51:
1960:
1952:
1929:"Transmission Beyond 100 Mbit/s Using LED Both as a Transmitter and Receiver"
1276:
333:
322:
288:
1265:
1253:
17:
747:
311:
246:
30:
1381:
214:
The voltage versus current characteristics of an LED is similar to any
1927:
Stepniak, G.; Kowalczyk, M.; Maksymiuk, L.; Siuzdak, J. (2015-10-01).
975:
is 0 (to simplify examples), the resistance is calculated as follows:
922:
262:
1424:. If the voltage is of the wrong polarity, the device is said to be
1928:
1797:
1440:
supply when properly current-limited for forward-biased operation.
884:
collector-emitter saturation voltage from the transistor datasheet.
1843:"Very Low-Cost Sensing and Communication Using Bidirectional LEDs"
1491:
1474:
1264:
1252:
1240:= (5V - 1.8V) / 1K ohm = (5 - 1.8) / 1000 = 0.0032, which is 3.2mA
743:
328:
LEDs with built-in series resistors are available. These may save
240:
215:
29:
1537:- powering an LED using 1.5V battery and voltage booster circuit
1480:
1372:
technology to drive LEDs dates back to the late 1960s. In 1969,
681:
343:, considering that the supply voltage is offset by the diode's
1646:"Electrical properties of GaN LEDs & Parallel connections"
1413:
1376:
introduced the HP Model 5082-7000 Numeric
Indicator, an early
782:
630:
596:{\displaystyle I_{led}}={V_{power}-V_{f}-V_{switch} \over R}
474:{\displaystyle R={V_{power}-V_{f}-V_{switch} \over I_{led}}}
249:
with its internal LED elements and driver circuitry exposed.
370:, which varies little over the range of useful currents:
339:
The value for the series resistance may be obtained from
1680:
Borden, Howard C.; Pighini, Gerald P. (February 1969).
1891:
Bent, Sarah, Aoife
Moloney and Gerald Farrell (2006).
1841:
Dietz, Paul, William
Yerazunis, Darren Leigh (2003).
1291:
1213:
1187:
1160:
1121:
1090:
1051:
1024:
985:
939:
894:
845:
799:
760:
721:
715:
is the LED's forward voltage drop in volts when lit.
694:
647:
615:
500:
379:
349:
183:
177:
If the supply voltage is close or equal to the LED's
153:
115:
72:
742:
and the LED's light frequency (which we perceive as
1573:2.2.5 Temperature dependence of the energy bandgap
1304:
1232:
1193:
1173:
1146:
1096:
1070:
1037:
1010:
967:
913:
876:
827:
773:
734:
707:
672:
621:
595:
473:
362:
196:
166:
128:
85:
1486:In addition to emission, an LED can be used as a
933:Using the algebraic formula (above) and assuming
34:Simple LED (Light Emitting Diode) circuit diagram
1543:- relation between band gap and photon frequency
1408:, which illuminate regardless of the electrical
1275:Strings of multiple LEDs are normally connected
1897:Irish Signals and Systems Conference, 2006. IET
1735:"Are There Standards Governing Polarity Marks?"
1396:and becoming the basis for later LED displays.
1334:such that when the clock displays "12:34" on a
332:space, and are especially useful when building
1549:- relation between forward voltage and current
8:
1909:: CS1 maint: multiple names: authors list (
1876:: CS1 maint: multiple names: authors list (
1760:"How to Build a PCB: Diode Polarity (No,..."
1498:detection and bidirectional communications.
1922:
1920:
633:, typically rounded up to the next higher
1850:Mitsubishi Electric Research Laboratories
1796:
1629:
1627:
1296:
1290:
1218:
1212:
1186:
1165:
1159:
1126:
1120:
1089:
1056:
1050:
1029:
1023:
990:
984:
944:
938:
899:
893:
850:
844:
804:
798:
765:
759:
726:
720:
699:
693:
652:
646:
614:
567:
554:
529:
522:
505:
499:
457:
431:
418:
393:
386:
378:
354:
348:
283:, and buck-boost converters) are used in
188:
182:
158:
152:
120:
114:
77:
71:
1836:
1834:
1832:
1595:
1593:
781:ranges from around 1.7 to 2.0 volts for
1559:
1902:
1869:
1785:IEEE Transactions on Power Electronics
1575:. Ece-www.colorado.edu. Archived from
1435:Most LEDs have relatively low reverse
27:Electrical circuit used to power a LED
921:is the desired current of the LED in
7:
785:LEDs to around 2.8 to 4.0 volts for
1709:The Vintage Technology Association
1353:An extension of this technique is
25:
1933:IEEE Photonics Technology Letters
1567:Van Zeghbroeck, Bart J. (1997).
1519:
680:is the power supply voltage in
1603:Power Supplies for LED Driving
869:
857:
218:. Current is approximately an
1:
1269:Schematic of LEDs in parallel
273:Switched-mode power supplies
222:of voltage according to the
1705:"Hewlett-Packard 5082-7000"
1257:Schematic of LEDs in series
877:{\displaystyle V_{CE(sat)}}
210:Power source considerations
2027:
1392:technology, replacing the
1357:where the ability of some
1320:
968:{\displaystyle V_{switch}}
828:{\displaystyle V_{switch}}
1815:10.1109/TPEL.2017.2655884
1610:. pp. 20–22, 39–41.
1147:{\displaystyle V_{power}}
1011:{\displaystyle V_{power}}
673:{\displaystyle V_{power}}
1953:10.1109/LPT.2015.2451006
1655:. Nichia. Archived from
1541:Planck–Einstein relation
1457:flicker fusion threshold
1406:incandescent light bulbs
1386:research and development
145:Kirchhoff's circuit laws
1986:LED Resistor Calculator
1690:Hewlett-Packard Journal
1547:Shockley diode equation
1233:{\displaystyle I_{led}}
1071:{\displaystyle I_{led}}
914:{\displaystyle I_{led}}
224:Shockley diode equation
137:depends on its material
1739:www.circuitinsight.com
1682:"Solid-State Displays"
1600:Winder, Steve (2011).
1483:
1461:pulse-width modulation
1306:
1270:
1258:
1234:
1195:
1175:
1148:
1106:common resistor values
1098:
1072:
1039:
1012:
969:
915:
878:
829:
775:
736:
709:
684:, e.g. 9-volt battery.
674:
623:
597:
475:
364:
250:
198:
168:
130:
87:
35:
2006:Light-emitting diodes
1478:
1471:LED as a light sensor
1384:, who had engaged in
1348:seven-segment display
1336:seven-segment display
1307:
1305:{\displaystyle V_{f}}
1268:
1256:
1235:
1196:
1176:
1174:{\displaystyle V_{f}}
1149:
1099:
1073:
1040:
1038:{\displaystyle V_{f}}
1013:
970:
927:common resistor value
916:
879:
830:
776:
774:{\displaystyle V_{f}}
737:
735:{\displaystyle V_{f}}
710:
708:{\displaystyle V_{f}}
675:
624:
598:
476:
365:
363:{\displaystyle V_{f}}
330:printed circuit board
318:are still practical.
244:
199:
197:{\displaystyle V_{f}}
169:
167:{\displaystyle V_{f}}
131:
129:{\displaystyle V_{f}}
88:
86:{\displaystyle V_{f}}
33:
1289:
1211:
1185:
1158:
1119:
1088:
1049:
1022:
983:
937:
892:
843:
797:
758:
746:) increase with the
719:
692:
645:
613:
497:
377:
347:
220:exponential function
181:
151:
113:
70:
59:light-emitting diode
2011:American inventions
1945:2015IPTL...27.2067S
1807:2017ITPE...32.9293T
1715:on 17 November 2014
1430:alternating current
1343:multiplexed display
253:An active constant
1527:Electronics portal
1484:
1370:integrated circuit
1302:
1271:
1259:
1230:
1191:
1171:
1144:
1094:
1068:
1035:
1008:
965:
911:
874:
825:
771:
732:
705:
670:
619:
517:
471:
360:
300:integrated circuit
251:
194:
164:
126:
83:
36:
1939:(19): 2067–2070.
1791:(12): 9293–9306.
1437:breakdown voltage
1194:{\displaystyle R}
1097:{\displaystyle R}
629:is resistance in
622:{\displaystyle R}
592:
469:
16:(Redirected from
2018:
1973:
1972:
1924:
1915:
1914:
1908:
1900:
1888:
1882:
1881:
1875:
1867:
1865:
1864:
1858:
1852:. Archived from
1847:
1838:
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1774:
1773:
1771:
1769:
1756:
1750:
1749:
1747:
1745:
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1725:
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1720:
1711:. Archived from
1701:
1695:
1694:
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1677:
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1667:
1661:
1653:Application Note
1650:
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1622:
1621:
1597:
1588:
1587:
1585:
1584:
1564:
1529:
1524:
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1451:Pulsed operation
1359:microcontrollers
1311:
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834:
832:
831:
826:
824:
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780:
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772:
770:
769:
754:. Consequently,
741:
739:
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733:
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714:
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706:
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703:
679:
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57:used to power a
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2001:Analog circuits
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1763:EEWeb Community
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1625:
1618:
1599:
1598:
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1582:
1580:
1566:
1565:
1561:
1556:
1525:
1518:
1515:
1473:
1453:
1402:
1390:digital display
1374:Hewlett-Packard
1325:
1319:
1292:
1287:
1286:
1273:
1272:
1261:
1260:
1249:
1214:
1209:
1208:
1183:
1182:
1161:
1156:
1155:
1122:
1117:
1116:
1086:
1085:
1052:
1047:
1046:
1025:
1020:
1019:
986:
981:
980:
940:
935:
934:
895:
890:
889:
846:
841:
840:
800:
795:
794:
761:
756:
755:
752:LED's materials
722:
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648:
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611:
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563:
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453:
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389:
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375:
374:
350:
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344:
308:
306:Series resistor
285:LED flashlights
239:
212:
184:
179:
178:
154:
149:
148:
116:
111:
110:
103:
73:
68:
67:
28:
23:
22:
15:
12:
11:
5:
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1980:External links
1978:
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1538:
1531:
1530:
1514:
1511:
1472:
1469:
1452:
1449:
1426:reverse biased
1422:forward-biased
1401:
1398:
1355:Charlieplexing
1321:Main article:
1318:
1315:
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1262:
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1203:
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1125:
1115:Example2 with
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1111:
1110:
1109:
1093:
1080:
1079:
1065:
1062:
1059:
1055:
1032:
1028:
1005:
1002:
999:
996:
993:
989:
979:Example1 with
962:
959:
956:
953:
950:
947:
943:
931:
930:
908:
905:
902:
898:
886:
885:
871:
868:
865:
862:
859:
856:
853:
849:
837:BJT transistor
822:
819:
816:
813:
810:
807:
803:
791:
790:
768:
764:
729:
725:
702:
698:
686:
685:
667:
664:
661:
658:
655:
651:
639:
638:
635:resistor value
618:
604:
603:
591:
585:
582:
579:
576:
573:
570:
566:
562:
557:
553:
549:
544:
541:
538:
535:
532:
528:
521:
514:
511:
508:
504:
466:
463:
460:
456:
449:
446:
443:
440:
437:
434:
430:
426:
421:
417:
413:
408:
405:
402:
399:
396:
392:
385:
382:
357:
353:
307:
304:
287:and household
260:depletion-mode
255:current source
247:LED light bulb
238:
237:MOSFET drivers
235:
211:
208:
191:
187:
161:
157:
123:
119:
102:
99:
95:current source
80:
76:
26:
24:
14:
13:
10:
9:
6:
4:
3:
2:
2023:
2012:
2009:
2007:
2004:
2002:
1999:
1998:
1996:
1987:
1984:
1983:
1979:
1970:
1966:
1962:
1958:
1954:
1950:
1946:
1942:
1938:
1934:
1930:
1923:
1921:
1917:
1912:
1906:
1898:
1894:
1887:
1884:
1879:
1873:
1859:on 2009-02-05
1855:
1851:
1844:
1837:
1835:
1833:
1829:
1824:
1820:
1816:
1812:
1808:
1804:
1799:
1794:
1790:
1786:
1779:
1776:
1764:
1761:
1755:
1752:
1740:
1736:
1730:
1727:
1714:
1710:
1706:
1700:
1697:
1692:
1691:
1683:
1676:
1673:
1662:on 2007-08-09
1658:
1654:
1647:
1641:
1638:
1635:
1630:
1628:
1624:
1619:
1617:9780080558578
1613:
1609:
1605:
1604:
1596:
1594:
1590:
1579:on 2009-02-01
1578:
1574:
1570:
1563:
1560:
1553:
1548:
1545:
1542:
1539:
1536:
1533:
1532:
1528:
1522:
1517:
1512:
1510:
1508:
1503:
1499:
1497:
1496:ambient light
1493:
1489:
1482:
1479:Mobile phone
1477:
1470:
1468:
1464:
1462:
1458:
1450:
1448:
1446:
1445:surface mount
1441:
1438:
1433:
1431:
1427:
1423:
1419:
1415:
1411:
1407:
1399:
1397:
1395:
1391:
1387:
1383:
1379:
1375:
1371:
1366:
1364:
1360:
1356:
1351:
1349:
1344:
1339:
1337:
1333:
1332:digital clock
1328:
1324:
1316:
1314:
1297:
1293:
1284:
1280:
1278:
1267:
1255:
1246:
1225:
1222:
1219:
1215:
1207:
1206:
1205:
1204:
1188:
1166:
1162:
1139:
1136:
1133:
1130:
1127:
1123:
1114:
1113:
1107:
1091:
1084:
1083:
1082:
1081:
1063:
1060:
1057:
1053:
1030:
1026:
1003:
1000:
997:
994:
991:
987:
978:
977:
976:
960:
957:
954:
951:
948:
945:
941:
928:
924:
906:
903:
900:
896:
888:
887:
866:
863:
860:
854:
851:
847:
838:
820:
817:
814:
811:
808:
805:
801:
793:
792:
788:
784:
766:
762:
753:
749:
745:
727:
723:
700:
696:
688:
687:
683:
665:
662:
659:
656:
653:
649:
641:
640:
636:
632:
616:
609:
608:
607:
589:
583:
580:
577:
574:
571:
568:
564:
560:
555:
551:
547:
542:
539:
536:
533:
530:
526:
519:
512:
509:
506:
502:
464:
461:
458:
454:
447:
444:
441:
438:
435:
432:
428:
424:
419:
415:
411:
406:
403:
400:
397:
394:
390:
383:
380:
373:
372:
371:
355:
351:
342:
337:
335:
331:
326:
324:
319:
315:
313:
305:
303:
301:
298:
294:
293:Power MOSFETs
290:
286:
282:
278:
274:
270:
268:
264:
261:
256:
248:
243:
236:
234:
231:
227:
225:
221:
217:
209:
207:
205:
189:
185:
175:
159:
155:
146:
142:
138:
121:
117:
107:
101:Basic circuit
100:
98:
96:
78:
74:
64:
60:
56:
53:
49:
45:
41:
32:
19:
1936:
1932:
1905:cite journal
1896:
1886:
1872:cite journal
1861:. Retrieved
1854:the original
1849:
1788:
1784:
1778:
1766:. Retrieved
1762:
1754:
1742:. Retrieved
1738:
1729:
1717:. Retrieved
1713:the original
1708:
1699:
1688:
1675:
1664:. Retrieved
1657:the original
1652:
1640:
1602:
1581:. Retrieved
1577:the original
1572:
1562:
1504:
1500:
1485:
1465:
1454:
1442:
1434:
1425:
1421:
1418:p-n junction
1403:
1367:
1352:
1340:
1329:
1326:
1281:
1274:
932:
605:
338:
327:
320:
316:
309:
271:
267:Low drop-out
252:
232:
228:
213:
206:
176:
108:
104:
63:voltage drop
47:
43:
37:
1535:Joule thief
1507:multiplexed
1378:LED display
1368:The use of
1323:LED display
1317:LED display
44:LED circuit
40:electronics
1995:Categories
1899:: 345–349.
1863:2009-09-07
1798:2002.00029
1666:2007-08-13
1583:2009-02-15
1554:References
1488:photodiode
1467:cool off.
1394:Nixie tube
1247:LED arrays
334:prototypes
245:Household
109:The LED's
52:electrical
48:LED driver
18:LED driver
1961:1041-1135
1719:15 August
1447:devices.
1363:tri-state
1341:However,
1277:in series
1201:= 1K ohm:
561:−
548:−
425:−
412:−
341:Ohm's law
323:coin cell
312:resistors
289:LED lamps
141:Ohm's law
1969:23986334
1823:43054007
1768:19 April
1744:19 April
1513:See also
1410:polarity
1400:Polarity
1283:Parallel
1181:= 1.8V,
1045:= 1.8V,
748:band gap
1941:Bibcode
1803:Bibcode
1693:: 2–12.
1569:"2.2.5"
1404:Unlike
1382:HP Labs
1154:of 5V,
1018:of 9V,
750:of the
606:where:
310:Series
55:circuit
1967:
1959:
1821:
1614:
1608:Newnes
1078:= 5mA:
839:, use
787:violet
492:
489:
485:
482:
275:(e.g.
263:MOSFET
50:is an
1965:S2CID
1857:(PDF)
1846:(PDF)
1819:S2CID
1793:arXiv
1685:(PDF)
1660:(PDF)
1649:(PDF)
1492:light
789:LEDs.
744:color
682:volts
297:Power
281:boost
216:diode
42:, an
1957:ISSN
1911:link
1878:link
1770:2019
1746:2019
1721:2019
1612:ISBN
1481:IrDA
1414:LEDs
923:amps
631:ohms
277:buck
143:and
1949:doi
1811:doi
1490:in
1361:to
783:red
321:In
46:or
38:In
1997::
1963:.
1955:.
1947:.
1937:27
1935:.
1931:.
1919:^
1907:}}
1903:{{
1895:.
1874:}}
1870:{{
1848:.
1831:^
1817:.
1809:.
1801:.
1789:32
1787:.
1737:.
1707:.
1687:.
1651:.
1626:^
1606:.
1592:^
1571:.
1412:,
1108:).
487:or
291:.
279:,
139:.
1971:.
1951::
1943::
1913:)
1880:)
1866:.
1825:.
1813::
1805::
1795::
1772:.
1748:.
1723:.
1669:.
1620:.
1586:.
1298:f
1294:V
1226:d
1223:e
1220:l
1216:I
1189:R
1167:f
1163:V
1140:r
1137:e
1134:w
1131:o
1128:p
1124:V
1092:R
1064:d
1061:e
1058:l
1054:I
1031:f
1027:V
1004:r
1001:e
998:w
995:o
992:p
988:V
961:h
958:c
955:t
952:i
949:w
946:s
942:V
907:d
904:e
901:l
897:I
870:)
867:t
864:a
861:s
858:(
855:E
852:C
848:V
821:h
818:c
815:t
812:i
809:w
806:s
802:V
767:f
763:V
728:f
724:V
701:f
697:V
666:r
663:e
660:w
657:o
654:p
650:V
637:.
617:R
590:R
584:h
581:c
578:t
575:i
572:w
569:s
565:V
556:f
552:V
543:r
540:e
537:w
534:o
531:p
527:V
520:=
513:d
510:e
507:l
503:I
465:d
462:e
459:l
455:I
448:h
445:c
442:t
439:i
436:w
433:s
429:V
420:f
416:V
407:r
404:e
401:w
398:o
395:p
391:V
384:=
381:R
356:f
352:V
190:f
186:V
160:f
156:V
122:f
118:V
79:f
75:V
66:(
20:)
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