March 06, 2023

Схема блока питания 5 вольт

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С. М.

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С. М., 552d ago

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LM7805

LM7805

It seems that LM7805 is one possible solution for a 5V power supply. People say that by replacing the LM7812 stabilizer with the LM7805, it is possible to get a 5V stabilized power supply [1] . Additionally, I think it is necessary to prepare electronic components and accesssories in order to build the power supply block [3] . Furthermore, the current output on the ATX 5V standby rail is recommended at 2A, but it seems that older designs may be rated at 1A while newer designs are likely to use a switching regulator [4] [8] .
LM138

LM138

It seems that the LM138 is an option for a 5 volt power supply as it has a 5A output and onboard current limiting. People say that this component can regulate 20A+some headroom with beefy heatsinks [5] , making it a viable choice for larger power needs. However, some users have suggested that instead of disabling protection devices, the loads should be changed to suit the power supply [7] , and very old power supplies may be rated for 1 Amp [8] , so it's important to take into account the design of the power supply before selecting components.
Polyfuse

Polyfuse

It seems that Polyfuse is a possible solution for regulating the current on an ATX power supply if you want 5 Volts. Sources [3] [5] mention PTC Resetable Fuses as a way of over/under voltage protection, and source [6] suggests using a polyfuse for current limiting with proper heatsinking. Additionally, this might be suitable for very old power supplies which may be rated for 1 Amp [5] .
PTC Resetable Fuse

PTC Resetable Fuse

It seems that a PTC Resetable Fuse can act like a circuit breaker, stopping the supply when too much current is drawn [6] . This could be useful for preventing overvoltage or undervoltage when using an ATX power supply to provide 5V [3] . Although ATX recommends 2A of current on the +5VSB rail, it seems that 0.5 Amp or lower should be a safe assumption when using a newer power supply design [8] .
LM7812

LM7812

It seems that LM7812 might be a suitable solution for obtaining 5V stable power supply when building a block power supply. According to source 1, it can be used in place of LM7805. Additionally, the source suggests that one should use a heatsink for higher than 0.5A of load, as well as prepare electronic components and tools for assembly.
All answers

All answers

  • LM7805
  • LM138
  • Polyfuse
  • PTC Resetable Fuse
  • LM7812
  • ATX 300w.png
  • ATX-450P-DNSS.zip
  • AcBel_400w.zip
  • ATX-300P4-PFC.png
  • ATX-P6.gif
  • ATXPower.rar
  • GPS-350EB-101A.pdf
  • GPS-350FB-101A.pdf
  • CTG-350-500.png
  • CFT-370_430_460.pdf

    • Source of Voltage

    [The source of voltage for a power supply block 5 volts is typically an AC voltage, with a suitable transformer used to convert it to the desired output. For a 12V supply, this can be done with an LM7812 regulator. [1] ]

    Voltage Regulation

    [Voltage regulation involves maintaining a steady voltage output despite changes in the input voltage or load. This is done with stabilizing devices such as the LM7805 for 5V supplies, and should be combined with a heat sink for greater load capacity. [1] ]

    Components and Tools

    [When building a power supply block, one must prepare the necessary components such as transformers, diodes, microchips, resistors and capacitors. Additionally, tools such as soldering iron and other mounting equipment will be needed. [1] ]

    Heat Sink

    [Heat sinks are necessary when pushing higher currents through microchips in order to prevent them from overheating. A suitable radiator should be used to dissipate the extra heat generated by the device. [1] ]

    Filtering Circuits

    [Filtering circuits are used to reduce interference from both synphase and differential sources. These include snubber diodes and capacitors (Cy and Cx/Cx1) which help filter out unwanted noise. [3] ] [4]

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    Research

    Source: "A Maker's Guide to ATX Power Supplies : 6 Steps..." (from web, www.instructables.com)

    • ATX connectors
      • ATX connectors come in two common sizes: 20 and 24 pins.
      • They can be mated together with an adapter to function as a 24-pin connector.
      • Adapters are also a good source of pre-wired connectors.
    • Wire colors and functions in the PSU
      • Colors are typically standardized.
      • Each pin in an ATX connector is rated to a max of 6 amps.
      • PSUs require a minimum load in order to provide consistent voltage, and this can be achieved through the use of a 5 or 10 ohm, 10 watt resistor.
      • Some PSUs have a minimum load listed on their spec sheet.
    • Other Connectors
      • 4-pin molex connectors (aka “Peripheral Connectors”)
      • +12V2 connector (aka “P4 12V” connector)
      • PCI Express (PCI-e) power connector
      • SATA power connector
      • Floppy drive power connector
      • Aux power Connector(s)
    • Tips, Suggestions, & Anomalies
      • Test the PSU for functionality before modifying it.
      • Install fuses on the outputs, not the ground.
      • Leave enough space for airflow in the PSU’s enclosure.
      • Be careful when drilling holes in the case to keep metal filings out of the electronics.
      • To figure out which of a PSU’s +12V lines are on different rails, use a multimeter to check resistance between the +12V pins on the different connectors.

    Source: "Current limiting a ATX Power supply if I want v..." (from reddit, r/AskElectronics)

    • Use a LM317:
      • Max current rating is 1.5-2A with proper heatsinking
    • Use a polyfuse or “PTC Resetable Fuse”:
      • Acts like a circuit breaker, stops the supply when too much current is drawn
    • Use an LM138:
      • 5A output with onboard current limiting
    • Use external pass transistors driven by the LM137:
      • Can regulate 20A+some headroom with beefy heatsinks

    Source: "Current output on ATX 5v standby rail?" (from reddit, r/AskElectronics)

    • ATX recommends 2A, but the actual minimum is 720 mA
      • According to a user comment, a newer design of an ATX power supply is likely to use a switching regulator for +5VSB output
      • Another user comment suggested 0.5 Amp or lower should be a safe assumption when using a newer power supply design
    • Very old power supplies may be rated for 1 Amp
      • According to a user comment, a brand called Transworld would shut down with a 1/2 amp load after 30 seconds

    Source: "ATX Power supply 5V rail Peak Current" (from web, electronics.stackexchange.com)

    None

    Source: "PC/ATX/PSU disable over/under voltage protection" (from reddit, r/AskElectronics)

    • Load the 12V rail:
      • The user suggests that the over/under voltage protection is being triggered due to lack of load on the 12V rail.
      • The user suggests that the LEDs should be connected to both the 5V and 12V rails.
    • Change the loads to suit:
      • The user suggests that instead of disabling protection devices, the loads should be changed to suit the power supply.

    💭  Looking into

    Are there any other power supply schematics with an output voltage of 5 Volts?

    💭  Looking into

    Are there any other sources for 5 Volt power supply schematics?

    💭  Looking into

    What is the maximum output voltage of the 400W ATX power supply produced by Acbel Politech Ink?

    💭  Looking into

    What type of components are necessary for this 450W ATX power supply produced by ACBEL ELECTRONIC (DONGGUAN) CO. LTD?

    💭  Looking into

    What type of functional annotations are present in ATX 300w.png?

    Source: "Skhema bloka pitaniia komp'iutera -- polnoe opi..." (from web, zapitka.ru)

    • Устройство и общая структурная схема
      • Источник питающих напряжений для ПК строится по обычной по традиционной схемотехнике, характерной для импульсных БП со стабилизацией напряжения.
    • Входные цепи
      • Плавкий предохранитель, сгорающий при повышении потребляемого тока сверх номинала, а также варистор
      • Элементы фильтрации: от синфазных помех (синфазный дроссель и конденсаторы Cy); от дифференциальных помех (конденсаторы Cx и Cx1).
    • Высоковольтны

    Source: "Skhemy blokov pitaniia i ne tol'ko." (from web, ab57.ru)

    • ATX 300w.png
      • A typical schematic of a 300W ATX power supply with functional annotations of the individual components of the schematic.
    • ATX-450P-DNSS.zip
      • A schematic of a 450W ATX power supply produced by ACBEL ELECTRONIC (DONGGUAN) CO. LTD.
    • AcBel_400w.zip
      • A schematic of a 400W ATX power supply produced by Acbel Politech Ink.
    • Alim ATX 250W (.png)
      • A schematic of a 250W Alim ATX power supply produced by SMEV J.M. in 2002.
    • atx-300p4-pfc.png
      • A schematic of a 300W ATX power supply (ATX-310T 2.03).
    • ATX-P6.gif
      • A schematic of a ATX-P6 power supply.
    • ATXPower.rar
      • Schematics of ATX 250 SG6105, IW-P300A2, and two unknown sources.
    • GPS-350EB-101A.pdf
      • A schematic of a 350W CHIEFTEC TECHNOLOGY power supply (GPS-350EB-101A).
    • GPS-350FB-101A.pdf
      • A schematic of a 350W CHIEFTEC TECHNOLOGY power supply (GPS-350FB-101A).
    • ctg-350-500.png
      • Schematics of Chieftec CTG-350-80P, CTG-400-80P, CTG-450-80P and CTG-500-80P power supplies.
    • cft-370_430_460.pdf
      • Schematics of Chieftec CFT-370-P12S, CFT-430-P12S, and CFT-460-P12S power supplies.
    • gpa-400.png
      • A schematic of a 400W Chieftec iArena GPA-400S8 power supply.
    • GPS-500AB-A.pdf
      • A schematic of a 500W Chieftec power supply (GPS-500AB-A).
    • GPA500S.pdf
      • A schematic of a 500W CHIE

    Source: "Skhema bloka pitaniia na 5 Vol't" (from web, radio-magic.ru)

    • Схема блока питания на 5 Вольт
      • Для питания того или иного проекта возникает необходимость в качественном напряжении номиналом в 5 Вольт
      • На выходе диодного моста получается напряжение которое имеет полярность, но оно не стабильно и имеются нелинейные искажения, пульсации. Для сглаживания этих пульсаций стоит конденсатор С4.
      • Напряжение с которого подается на стабилизирующее устройство DA1 которое на выходе дает 5 Вольт
    • Характеристики микросхемы KP142EH5A
      • Напря

    Source: "Skhema komp'iuternogo bloka pitaniia 400w: Radi..." (from web, soto-lux.ru)

    None

    Source: "Blok pitaniia 1,5v, 3,3v, 5v, 12v, 24v, samomu ..." (from web, www.110volt.ru)

    • Схема блока питания 12в 30А
      • Для получения 5 вольтового стабилизированного питания, можно заменить стабилизатор LM7812 на LM7805.
      • Для увеличения нагрузочной способности более 0,5 ампер, понадобится радиатор для микросхемы.
      • Необходимо подготовить электронные компоненты, детали и принадлежности из которого будет собираться сам блок.
      • Силовой понижающий трансформатор, диоды и радиатор для микросхемы.
      • Инструменты для монтажа.

    💭  Looking into

    What is the best 5-volt power supply block?