Questions tagged [ac-dc]
Questions regarding the safe and effecient design and implementation of AC voltage to DC voltage supplies. Typically Mains to some lower DC voltage.
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Getting a small AC "reference" from a DC power supply?
I have a 1970s-vintage video generating board that I'd like to do some work with. I do not have the PSU that it was meant to be connected to. The board wants +/-5V, -12V DC, plus a small 6V AC "...
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Why doesn't SMPS controller VCC capacitor get fully charged to 310 V?
Most SMPS circuits have a startup circuit like the one in the schematic below:
The rectified 310 V goes through Rstartup1 and Rstartup2 to fill Cvcc to UVLO limit and the controller IC starts working....
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Why are there two common-mode chokes on AC input?
This is a part of an AC/DC converter schematic from TI.
There are two common-mode chokes on the AC input side.
I have no idea why two CMCs (L100, L101) are used.
Could anyone explain this?
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Does AC wire ampere rating depend on end DC load current pull? [closed]
So between my 220V 50Hz AC source and my 12V 5-10Amps DC load I have placed a SMPS power supply which converts 220V AC to 12V DC and is rated to supply 16Amps. Now my cable to connect the 220V AC with ...
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AC to DC conversion speed
I am using a relay and an arduino to quickly turn on and off lights for a Christmas light show. So far all of the lights have been AC power. However I just got a snowman that runs on 12v DC power ...
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3
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Isolated vs. Non-Isolated AC Mains to 5v Converter
I am working on an internet connected lamp project that includes an AC dimmer and touch sensor. I am wanting to design a custom PCB but am confused if I should use an isolated or non-isolated ...
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Average Voltage of a fully controlled bridge rectifier
I have been given the above equation for the average voltage of a fully controlled bridge rectifier. Apparently this is only valid for continuous load current conditions. Why is this the case?
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How do medical SMPS achieve lower Earth leakage compared to "regular" AC-DC SMPS?
When using a "regular" (i.e. not medical grade) AC-DC isolated SMPS in the following fashion, a strong mains common-mode voltage is created on the DC side due to - I believe - the stray ...
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Safety in AC/DC converter [closed]
To make an AC/DC converter with 230 V input, I have seen several circuits. Circuits that use a transformer to lower the voltage and that filter the signal to obtain a stable low voltage. I have also ...
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Can I power an MCU using a 3.3V AC/DC module converter?
I'm designing a board that will connect to 230V AC. I found some ready to use AC/DC modules that can output 3.3V DC Here's the list from Mouser.
Can I power an MCU directly from this output?. I'm ...
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Why is there 120VAC 60Hz when probing a barrel jack on the DC side with the ground reference being the outlet?
I noticed that there is an AC signal on the DC side of the barrel jack. on the casing and the internal male probe. When I touch my oscilloscope probe to the + or - of the barrel jack with the ground ...
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How to protect a power supply
Enthusiast here, with no particular electrical engineering knowledge.
I have ordered a power supply, similar to this one in the way it is built:
Here are the specs:
Input is 230V AC
Output is 48V DC ...
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AC\DC misbehaving when DC\DC converter connected as a load
I am feeding the output of an isolated ACDC converter (this one) into a DCDC converter (that one), and the ripple out of the ACDC supply jumps by a factor of 5 when the DCDC converter is connected - ...
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DK1203 Flyback SMPS - How does it work?
Has anyone come across a DK1203 SMPS like this? I've come across ICs like the FSGN300N that have a startup pin and aux coil to supply the IC. How would the self-supply circuit in the DK1203 work? In ...
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Multiple AC-DC power supplies: one direct AC wall plug or two?
I'm building a data acquisition system that needs to power sensors and a high voltage contactor at 24Vdc, 12Vdc, and 5Vdc. After reading another post, it seems it is best to use separate AC-DC power ...
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