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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Computer power supplies usually have higher efficiency on 230V than on 115V. Why?
As seen here in the example, this particular power supply (and most others too) has higher efficiency when running on 230V. Given that computer power supplies are usually required to output a ...
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Help me understand the relationship between positive, negative, neutral and ground in AC and DC
This question stems from notations on schematics and seemingly conflicting information I'm seeing. I suspect that I'm seeing different vernacular for the same concepts--but I'm in a place where no one'...
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If we could start our electrical grid from scratch with today's technology, which would be the most efficient choice? AC or DC?
Lately, I’ve been reading about the many advantages of HVDC transmission systems for long distance transmission, undersea links, and others. The historical reason of why AC was picked over DC was ...
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Why is this power adapter transformerless?
I saw a battery charger that converts 220V AC to 6V DC without a transformer.
Now I am wondering why many (if not all) power adapters are using a transformer, is it about efficiency or about ...
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Does this AC to DC + breadboard setup have the ability to kill/severely hurt me?
I'm currently building a PC peripheral that uses an AC to DC converter to power a set of DC fans. I'm not a trained EE or electrician, so I want to make sure I'm not putting myself a risk with this ...
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Second opinion on PCB design for relay made in Altium
Edit: I have added the updated PCB design at the bottom over this post (for anyone curious about the progress)
And a big thanks to everyone who commented, it really helped me out a lot!
Original ...
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How do phone chargers have variable input voltage with constant output voltage?
My basic understanding is that a transformer can step down a voltage by the ratio of the primary and secondary windings, since this is a ratio the output is not constant.
Thus my question is, how ...
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Bridge rectifier: 4 diodes vs. single chip?
I notice (among the DIY audio enthusiasts at least) that when it comes time to design a power supply for an amplifier, DAC or whatever that the parts list will inevitably include something like "4 x ...
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Can a 50 Hz, 220 VAC transformer work on 40 Hz, 180VAC?
I am designing an AC to DC converter. My power source is a single phase synchronous alternator that has a voltage range of 170~260 VAC and a frequency of 40~60 Hz. Can i use a transformer designed on ...
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MOSFET failure in a high power AC-DC SMPS buck converter
I've made a AC-DC step down buck converter that converts 220 VAC to a variable 45 to 70 VDC at 5 to 10 A to charge a Li-Ion battery. I'm currently using ESP32 to drive a MOSFET driver (IR2110) to ...
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Is it safe to use a DC power adapter that isn't UL Listed or CSA certified?
I picked up a 9V switching DC adapter from SparkFun a while back, but I've been hesitant to use it because it doesn't have any of the usual "safety" approvals that you normally see on power adapters (...
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AC adapter: Input power vs Output power
When I look at, let's say an iPad AC adapter, the input/output rating on the charger states:
Input: 100-240V 0.45A (AC)
Output: 5.1V 2.1A (DC)
I know that the ...
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Is it possible to step down 240 AC to 5 DC without transformer?
Microcontroller which is controlling mains voltage circuit requires 5 volts to operate.
Is it realistic to use diode bridge followed by capacitor to straighten the ac wave and then use voltage divider ...
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Connecting two DC wallwarts in series - to produce dual DC supply
I have two 9 V, 300 mA wallwarts and would like to connect them in series to produce +9 V, 0 V and -9 V. This can be done with two 9 V batteries (as seen below), but can I do this with two non-...
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Purpose of capacitor across transformer in AC-DC power supply? [duplicate]
I have been looking to buy a AC-DC 5v power supply module to power a mains relay in a circuit I am making. I came across a couple of different models on eBay and am trying to understand their basic ...
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