122:
258:
251:
25:
232:
225:
275:
282:
364:
No real voltage source is ideal; all have a non-zero effective internal resistance, and none can supply unlimited current. However, the internal resistance of a real voltage source is effectively modeled in linear circuit analysis by combining a non-zero resistance in series with an ideal voltage
311:
of an ideal voltage source is zero; it is able to supply or absorb any amount of current. The current through an ideal voltage source is completely determined by the external circuit. When connected to an open circuit, there is zero current and thus zero power. When connected to a
199:
across its terminals. It is often used as a mathematical abstraction that simplifies the analysis of real electric circuits. If the voltage across an ideal voltage source can be specified independently of any other variable in a circuit, it is called an
427:
provides a constant current, as long as the load connected to the source terminals has sufficiently low impedance. An ideal current source would provide no energy to a short circuit and approach infinite energy and voltage as the
360:
that the original voltage source would provide. For the remainder of the circuit, nothing has changed: These two voltage sources together provide the same voltage, and the same current as the original one alone.
212:. A mathematical model of an amplifier will include dependent voltage sources whose magnitude is governed by some fixed relation to an input signal, for example. In the analysis of
462:
Since no ideal sources of either variety exist (all real-world examples have finite and non-zero source impedance), any current source can be considered as a voltage source with the
356:
Voltage sources in parallel shares the burden of current: If an exact duplicate of voltage is connected in parallel to the original one, either one of them will provide half of the
316:, the current through the source approaches infinity as the load resistance approaches zero (a short circuit). Thus, an ideal voltage source can supply unlimited power.
351:
216:, the whole network of interconnected sources and transmission lines can be usefully replaced by an ideal (AC) voltage source and a single equivalent impedance.
204:
voltage source. Conversely, if the voltage across an ideal voltage source is determined by some other voltage or current in a circuit, it is called a
89:
61:
68:
516:
108:
496:
179:, can be modeled for analysis purposes as a combination of an ideal voltage source and additional combinations of
42:
75:
46:
57:
536:
213:
566:
478:
366:
35:
145:
382:
289:
121:
82:
394:
390:
180:
473:
of each other and any non ideal source can be converted from one to the other by applying
8:
474:
413:
330:
308:
470:
176:
164:
551:
546:
512:
378:
412:
in series with the source. A real-world voltage source has a very low, but non-zero
531:
466:
448:
440:
417:
409:
357:
320:
172:
157:
541:
429:
398:
313:
153:
424:
242:
168:
257:
250:
560:
469:
and vice versa. Voltage sources and current sources are sometimes said to be
402:
152:. An ideal voltage source can maintain the fixed voltage independent of the
196:
160:. However, a real-world voltage source cannot supply unlimited current.
452:
406:
24:
437:
323:, they must have exactly the same voltage; Otherwise, it creates a
319:
If two ideal independent voltage source are directly connected in
372:
324:
274:
231:
224:
149:
456:
16:
Two-terminal electrical device able to maintain a fixed voltage
219:
389:
voltage source provides no energy when it is loaded by an
397:), but approaches infinite energy and current when the
281:
333:
171:. Real-world sources of electrical energy, such as
49:. Unsourced material may be challenged and removed.
345:
558:
195:is a two-terminal device that maintains a fixed
405:). Such a theoretical device would have a zero
327:in logic, similar to writing down the equation
373:Comparison between voltage and current sources
447:current source has a very high, but finite
432:approaches infinity (an open circuit). An
125:A schematic diagram of a voltage source,
109:Learn how and when to remove this message
186:
120:
484:
377:Most sources of electrical energy (the
559:
385:) are modeled as voltage sources. An
511:, Cambridge University Press, 1992
509:Electrical circuits: an introduction
455:current sources, impedance of a few
47:adding citations to reliable sources
18:
13:
214:faults on electrical power systems
148:device which can maintain a fixed
14:
578:
459:(at low frequencies) is typical.
280:
273:
256:
249:
230:
223:
23:
443:in parallel with the source. A
34:needs additional citations for
507:K. C. A. Smith, R. E. Alley ,
501:
497:An introduction to electronics
490:
420:, often much less than 1 ohm.
1:
287:
271:
263:
247:
237:
221:
7:
525:
367:Thévenin equivalent circuit
10:
583:
268:Controlled Current Source
265:Controlled Voltage Source
537:Bandgap voltage reference
210:controlled voltage source
133:, and creating a current
302:Symbols used for sources
163:A voltage source is the
436:current source has an
347:
137:
129:, driving a resistor,
348:
239:Ideal Voltage Source
187:Ideal voltage sources
124:
485:References and notes
331:
243:Ideal Current Source
193:ideal voltage source
43:improve this article
414:internal resistance
401:approaches zero (a
346:{\displaystyle 1=2}
309:internal resistance
479:Thévenin's theorem
393:(i.e. an infinite
343:
138:
552:Voltage regulator
547:Voltage reference
451:. In the case of
299:
298:
119:
118:
111:
93:
574:
532:Dependent source
520:
505:
499:
494:
475:Norton's theorem
467:source impedance
449:output impedance
441:output impedance
418:output impedance
410:output impedance
358:electric current
352:
350:
349:
344:
284:
277:
260:
253:
234:
227:
220:
114:
107:
103:
100:
94:
92:
58:"Voltage source"
51:
27:
19:
582:
581:
577:
576:
575:
573:
572:
571:
567:Analog circuits
557:
556:
542:Voltage divider
528:
523:
506:
502:
495:
491:
487:
430:load resistance
399:load resistance
375:
332:
329:
328:
314:load resistance
305:
304:
303:
189:
154:load resistance
115:
104:
98:
95:
52:
50:
40:
28:
17:
12:
11:
5:
580:
570:
569:
555:
554:
549:
544:
539:
534:
527:
524:
522:
521:
500:
488:
486:
483:
425:current source
423:Conversely, a
374:
371:
342:
339:
336:
301:
300:
297:
296:
293:
286:
285:
278:
270:
269:
266:
262:
261:
254:
246:
245:
240:
236:
235:
228:
218:
188:
185:
169:current source
156:or the output
142:voltage source
117:
116:
31:
29:
22:
15:
9:
6:
4:
3:
2:
579:
568:
565:
564:
562:
553:
550:
548:
545:
543:
540:
538:
535:
533:
530:
529:
518:
517:0-521-37769-2
514:
510:
504:
498:
493:
489:
482:
480:
476:
472:
468:
465:
460:
458:
454:
450:
446:
442:
439:
435:
431:
426:
421:
419:
415:
411:
408:
404:
403:short circuit
400:
396:
392:
388:
384:
380:
370:
368:
362:
359:
354:
340:
337:
334:
326:
322:
317:
315:
310:
294:
291:
288:
283:
279:
276:
272:
267:
264:
259:
255:
252:
248:
244:
241:
238:
233:
229:
226:
222:
217:
215:
211:
207:
203:
198:
194:
184:
182:
178:
174:
170:
166:
161:
159:
155:
151:
147:
143:
136:
132:
128:
123:
113:
110:
102:
99:November 2010
91:
88:
84:
81:
77:
74:
70:
67:
63:
60: –
59:
55:
54:Find sources:
48:
44:
38:
37:
32:This article
30:
26:
21:
20:
519:, pp. 11-13
508:
503:
492:
463:
461:
444:
433:
422:
391:open circuit
386:
376:
363:
355:
318:
306:
295:Single cell
209:
205:
201:
197:voltage drop
192:
190:
162:
141:
139:
134:
130:
126:
105:
96:
86:
79:
72:
65:
53:
41:Please help
36:verification
33:
202:independent
183:elements.
453:transistor
445:real-world
365:source (a
177:generators
69:newspapers
395:impedance
292:of cells
206:dependent
181:impedance
173:batteries
144:is a two-
561:Category
526:See also
438:infinite
321:parallel
146:terminal
457:megohms
383:battery
325:fallacy
290:Battery
158:current
150:voltage
83:scholar
515:
85:
78:
71:
64:
56:
471:duals
434:ideal
387:ideal
379:mains
167:of a
90:JSTOR
76:books
513:ISBN
464:same
416:and
381:, a
307:The
175:and
165:dual
62:news
477:or
407:ohm
369:).
208:or
191:An
45:by
563::
481:.
353:.
140:A
341:2
338:=
335:1
135:I
131:R
127:V
112:)
106:(
101:)
97:(
87:·
80:·
73:·
66:·
39:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
.svg)
.svg)
.svg)
