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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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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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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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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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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Why AC supply is rectified first before stepping voltage down?
I have opened one of my phone chargers and was trying to understand how it works.. I found IC MB6F just at AC input which came out to be a bridge rectifier.
My question is why AC is first rectified ...
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Calculating the True Power Factor in non-linear loads
In my circuit I am taking in 60 Hz 120 VAC from the power company and hooking it up to a AC/DC non-linear switching buck converter I am designing.
I know that:
true power factor = (displacement power ...
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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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Is PFC compulsory for AC/DC converters 75W and above?
I’m reading the user guide for a Microchip reference design of a 300W AC/DC converter. Section 1.2 starts with these requirements:
A conventional SMPS must implement PFC if it draws more than 75 ...
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Does a bridge rectifier care that much for AC frequency?
As I understand it, a bridge rectifier is a set of diodes that play a trick of logic that keeps the polarity positive.
So, within the context of a household DC transformer does it matter what the ...
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home socket with DC voltage
I'm wondering why, in a standard house, instead of using many low power AC-DC rectifier, there isn't a big (like 12V 20~50A) AC-DC rectifier which supplies some wall socket with a DC voltage?
In the ...
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LED Strip Light - Power supply issues
I'm making this right now - https://www.youtube.com/watch?v=qlMtakaa7u8
Each 5m roll of LED takes 60W power (http://www.ebay.com/itm/182028302443?rmvSB=true). He's using two of these rolls, so a ...
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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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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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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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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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