141:
22:
224:. Linear variable bench power supplies have existed since longer ago, dating back at least to the 1980s. Linear power supplies typically make clicking sounds while adjusting the voltage, caused by adjustment between transformer taps. This is done to reduce energy wasted to heat by widening or narrowing the selected section of the secondary side of the transformer to be as close above the user-selected output voltage as possible.
341:
294:
specified by the user ("over-current protection"), likewise over-voltage protection that cuts out power if the external voltage exceeds output, indicator displays with more digits (four or five instead of three), digital rather than analogue voltage control, and the ability to lock the power setting to prevent accidental adjustment. In addition to output voltage/current meters, few are equipped with a
232:
Switching-mode power supplies are more lightweight, efficient, and more compact at a similar power rating, making them suitable for high-power applications. The higher efficiency means less heat production at the same output power, thus less wasted energy and needed cooling. Additionally, they may be
122:
is an embedded circuit; it converts unregulated AC (alternating current) into a constant DC. With the help of a rectifier it converts AC supply into DC. Its function is to supply a stable voltage (or less often current), to a circuit or device that must be operated within certain power supply limits.
320:
Some power supplies have two output channels. These may be used at schools, as a multi-channel unit tends to cost less than two separate units due to shared hardware. High-end ones might allow internally connecting two channels to a series circuit to double the voltage limit. Few power supplies have
289:
Controls vary between power supply models. Many have rotary knobs for setting voltage and current, each usually with a "coarse" and "fine" knob, the former of which adjusts the parameter throughout the entire range, whereas the latter facilitates adjustment within a small surrounding range. Some
390:
At times regulated supplies can be much more complex. An example supply from a 1980s TV which used bidirectional interaction between the main supply and the line output stage to operate, generating a range of output voltages with varying amounts of stabilisation. Since neither stage could start
293:
Some, typically higher-end models, are equipped with additional features such as a button for toggling output power without having to switch the whole device on/off, a memory for shortcuts to voltage/current combinations, an option to automatically cut out power when reaching a current limit
391:
without the other running, the supply also included a kickstart system to pulse the system into operation. The supply also monitored voltages in the TV power circuitry, shutting down if these voltages went out of spec. For special applications, supplies can become even more complex.
127:). The type of stabilization used may be restricted to ensuring that the output remains within certain limits under various load conditions, or it may also include compensation for variations in its own supply source. The latter is much more common today.
796:
261:
Some high-current power supplies have a rear-sided output for high-current operation. Its poles are larger to support such currents and are usually initially covered by plastic caps. The poles can be connected to accordingly-sized
286:"). When the current demanded by the load exceeds the limit set by the user, the power supply automatically switches to the latter mode by regulating the voltage down so much as to prevent the current limit from being exceeded.
187:
A laboratory ("lab") power supply normally implies an accurate bench power supply, while a balanced or tracking power supply refers to twin supplies for use when a circuit requires both positive and negative supply rails).
348:
are optimized with the aim to support high currents per physical space at a given constant voltage. Due to optimization for a specific voltage rather than a range, they tend to be more compact at a similar output power
386:
IC. There are variations on this theme, such as supplies with multiple voltage lines, variable regulators, power control lines, discrete circuits and so on. Switched mode regulator supplies also include an inductor.
674:
237:, typically around 110 to 240 volts rather than a section of approximately twenty volts on only end of the range, to be able to operate internationally. Similar switching technology is used in
180:) electronic circuits, possibly with continuous variation of the output voltage, or just some preset voltages. Some have multiple selectable ranges of current/voltage limits which tend to be
212:
The linear type produces only very little noise (or "ripple voltage") and is less prone to external electromagnetic and radio frequency interference (EMI, RFI), making it preferable for
317:
or output current, the former of which cools faster while idle or low throughout intermittent power output, whereas the latter provides acoustic feedback of how much current is output.
407:
A quality switching-mode power supply can outlive a poorly designed linear one, but as linear power supplies rely on fewer delicate components, they tend to be less prone to failure.
313:, or both may be used. Heat sinks may be mounted externally or internally. Heat sinks are silent, whereas fans are more effective in cooling. Fan speed may adjust
290:
models lack the "fine" knob for current, as drawn electrical current is decided by the load at a given voltage, thus less important to be throttled precisely.
220:-related applications and for powering delicate circuitry. Linear power supplies also have fewer failable parts which increases longevity, and have a quicker
633:
177:
181:
86:
58:
553:
164:, -). Other power supplies may use the opposite order for indicators and connectors, and two different colours for the indicators.
39:
321:
a third auxiliary output channel that is typically less powerful. It is typically located near the right edge or at the center.
65:
443:
375:, resonant transformers, nonlinear resistors, loading resistors, neon stabiliser tubes, vibrating contact regulators etc.
72:
828:
105:
579:
54:
703:
43:
279:
720:
489:
234:
123:
The output from the regulated power supply may be alternating or unidirectional, but is nearly always DC (
201:
596:
Using a tap changes the voltage ratio of a transformer so that its secondary voltage stays at nominal.
314:
477:
371:
Many topologies have been used since the regulated supply was invented. Early technologies included
79:
535:
517:
32:
608:
328:
panel to measure external voltages have existed in the 1990s and possibly earlier, but portable
372:
741:
354:
466:
8:
379:
197:
157:
204:(full-bridge rectifier first), each with a different set of benefits and disadvantages:
221:
383:
161:
757:
378:
Modern regulated supplies mostly use a transformer, silicon diode bridge rectifier,
658:
283:
250:
153:
145:
423:
263:
213:
744:
with four digits after decimal on current meter, but only two on voltage meter.
124:
634:"Linear Power Supply vs. Switching Power Supply: Advantages and Disadvantages"
822:
310:
428:
242:
173:
345:
329:
238:
298:(power) meter which indicates the product of both in real time, and a
144:
D.C. variable bench power supply unit, with a digital display showing
325:
306:
140:
21:
729:
518:"Bausatzanleitung Labornetzgerät UNIWATT NG 304 (0...30V / 0...3A)"
675:"OPERATING INSTRUCTIONS – LABORATORY POWER SUPPLY UNIT (LPS 1305)"
340:
305:
Many models have a handle at the top for carrying. For cooling, a
478:
https://maplindownloads.s3-eu-west-1.amazonaws.com/n93cx-3658.pdf
295:
176:
capable of supplying a variety of output voltages useful for BE (
149:
554:"Linear Power Supplies for Audiophiles - Getting Closer to Live"
246:
217:
758:"Labornetzteil Test: Korad / RND 320 KA3005P - mit Videos"
299:
275:
467:
https://www.sparkfun.com/datasheets/Tools/382260_UM.pdf
786:: outputs A and B with 0-40V 3A, Output C with 3-6V 2A
536:"Labor-Netzgerät Uniwatt NG-500 Power-S Beha-Amprobe;"
324:
Bench power supply units equipped with an integrated
46:. Unsourced material may be challenged and removed.
659:Geti Laboratory power supply PS3020 0-30V/ 0-20A
820:
752:
750:
241:that charge battery-powered devices including
797:"Power Supply Design: Switch-Mode vs. Linear"
609:"Understanding Linear Power Supply Operation"
269:
135:
344:Fixed-voltage power supplies like these and
196:Variable bench power supplies exist both as
747:
533:
444:"Bedienungsanleitung Labornetzgerät PS900W"
668:
666:
366:
672:
106:Learn how and when to remove this message
438:
436:
339:
139:
721:"DC Power Supply PS-3010DF User Manual"
663:
512:
510:
416:
821:
359:Regulated power supplies in appliances
764:(in German). AFUG INFO. December 2018
433:
335:
507:
490:"Linear vs Switching Power Supplies"
44:adding citations to reliable sources
15:
13:
362:Various amplifiers and oscillators
14:
840:
332:have made that feature obsolete.
20:
789:
776:
735:
713:
696:
652:
626:
601:
572:
130:
31:needs additional citations for
704:"Korad KA3005D-2S user manual"
546:
527:
494:Advanced Conversion Technology
482:
471:
460:
401:
274:The front panel typically has
1:
801:Simply Smarter Circuitry Blog
394:
227:
7:
534:Roggenhofer, Peter (1988).
355:Mobile phone power adaptors
233:able to operate on a wider
10:
845:
270:Functionality and controls
202:switched-mode power supply
136:D.C. variable bench supply
638:resources.pcb.cadence.com
235:Mains input voltage range
207:
829:Electrical power control
424:Regulated Power Supplies
278:indicators for "C.V." ("
256:
200:(transformer first) and
191:
55:"Regulated power supply"
373:iron-hydrogen resistors
367:Topology and technology
350:
165:
120:regulated power supply
343:
143:
315:based on temperature
172:usually refers to a
40:improve this article
540:www.radiomuseum.org
380:reservoir capacitor
152:(right), and three
673:Voltcraft (2015).
523:(in German). 1997.
351:
336:Other applications
222:transient response
170:bench power supply
166:
803:. 23 October 2014
730:Manual - Dr.meter
449:(in German). 2017
384:voltage regulator
251:electric bicycles
182:anti-proportional
154:banana connectors
116:
115:
108:
90:
836:
813:
812:
810:
808:
793:
787:
780:
774:
773:
771:
769:
754:
745:
739:
733:
727:
725:
717:
711:
710:
708:
700:
694:
693:
691:
689:
682:asset.conrad.com
679:
670:
661:
656:
650:
649:
647:
645:
630:
624:
623:
621:
619:
613:
605:
599:
598:
593:
591:
576:
570:
569:
567:
565:
550:
544:
543:
531:
525:
524:
522:
514:
505:
504:
502:
500:
486:
480:
475:
469:
464:
458:
457:
455:
454:
448:
440:
431:
420:
408:
405:
284:constant current
282:") and "C.C." ("
280:constant voltage
264:crocodile clamps
247:laptop computers
111:
104:
100:
97:
91:
89:
48:
24:
16:
844:
843:
839:
838:
837:
835:
834:
833:
819:
818:
817:
816:
806:
804:
795:
794:
790:
781:
777:
767:
765:
756:
755:
748:
740:
736:
723:
719:
718:
714:
706:
702:
701:
697:
687:
685:
677:
671:
664:
657:
653:
643:
641:
632:
631:
627:
617:
615:
611:
607:
606:
602:
589:
587:
578:
577:
573:
563:
561:
552:
551:
547:
532:
528:
520:
516:
515:
508:
498:
496:
488:
487:
483:
476:
472:
465:
461:
452:
450:
446:
442:
441:
434:
421:
417:
412:
411:
406:
402:
397:
369:
338:
302:charging port.
272:
259:
230:
214:audio equipment
210:
194:
138:
133:
112:
101:
95:
92:
49:
47:
37:
25:
12:
11:
5:
842:
832:
831:
815:
814:
788:
775:
746:
734:
712:
695:
662:
651:
625:
600:
584:www.ecmweb.com
571:
560:. 29 June 2018
545:
526:
506:
481:
470:
459:
432:
414:
413:
410:
409:
399:
398:
396:
393:
368:
365:
364:
363:
360:
357:
337:
334:
271:
268:
258:
255:
229:
226:
209:
206:
193:
190:
137:
134:
132:
129:
125:direct current
114:
113:
28:
26:
19:
9:
6:
4:
3:
2:
841:
830:
827:
826:
824:
802:
798:
792:
785:
779:
763:
759:
753:
751:
743:
738:
731:
722:
716:
705:
699:
683:
676:
669:
667:
660:
655:
639:
635:
629:
610:
604:
597:
585:
581:
575:
559:
555:
549:
541:
537:
530:
519:
513:
511:
495:
491:
485:
479:
474:
468:
463:
445:
439:
437:
430:
426:
425:
419:
415:
404:
400:
392:
388:
385:
381:
376:
374:
361:
358:
356:
353:
352:
347:
342:
333:
331:
327:
322:
318:
316:
312:
308:
303:
301:
297:
291:
287:
285:
281:
277:
267:
265:
254:
252:
248:
244:
243:mobile phones
240:
236:
225:
223:
219:
215:
205:
203:
199:
189:
185:
183:
179:
178:bench testing
175:
171:
163:
159:
155:
151:
147:
142:
128:
126:
121:
110:
107:
99:
88:
85:
81:
78:
74:
71:
67:
64:
60:
57: –
56:
52:
51:Find sources:
45:
41:
35:
34:
29:This article
27:
23:
18:
17:
805:. Retrieved
800:
791:
784:VLP 2403 PRO
783:
778:
768:26 September
766:. Retrieved
762:afug-info.de
761:
737:
715:
698:
686:. Retrieved
681:
654:
642:. Retrieved
637:
628:
616:. Retrieved
614:. 2005-02-04
603:
595:
588:. Retrieved
586:. 1999-11-01
583:
574:
562:. Retrieved
557:
548:
542:(in German).
539:
529:
497:. Retrieved
493:
484:
473:
462:
451:. Retrieved
429:Google Books
422:
418:
403:
389:
377:
370:
323:
319:
304:
292:
288:
273:
260:
231:
211:
195:
186:
174:power supply
169:
167:
131:Applications
119:
117:
102:
93:
83:
76:
69:
62:
50:
38:Please help
33:verification
30:
726:. Long Wei.
684:. p. 4
580:"StackPath"
558:Audio Bacon
346:AC adapters
330:multimeters
239:AC adapters
148:(left) and
782:Voltcraft
453:2021-08-21
395:References
66:newspapers
807:25 August
742:DPS-305BF
688:22 August
644:21 August
618:25 August
590:25 August
564:25 August
499:25 August
326:voltmeter
307:heat sink
228:Switching
96:June 2012
823:Category
349:support.
709:. 2012.
296:wattage
150:voltage
146:current
80:scholar
640:. 2020
249:, and
208:Linear
198:linear
162:ground
82:
75:
68:
61:
53:
728:(via
724:(PDF)
707:(PDF)
678:(PDF)
612:(PDF)
521:(PDF)
447:(PDF)
257:Other
218:radio
192:Types
87:JSTOR
73:books
809:2021
770:2021
690:2021
646:2021
620:2021
592:2021
566:2021
501:2021
382:and
216:and
59:news
427:at
311:fan
300:USB
276:LED
42:by
825::
799:.
760:.
749:^
680:.
665:^
636:.
594:.
582:.
556:.
538:.
509:^
492:.
435:^
309:,
266:.
253:.
245:,
184:.
168:A
160:,
118:A
811:.
772:.
732:)
692:.
648:.
622:.
568:.
503:.
456:.
158:+
156:(
109:)
103:(
98:)
94:(
84:·
77:·
70:·
63:·
36:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
