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.
443
questions
2
votes
2
answers
636
views
Electrical circuit / transformer in series?
I would like to pull out 5v 3A max in series from an already existing connection from the mains 240v 40A connection.
Current circuit:
What I would like to implement:
What are the possible problems ...
- 21
38
votes
3
answers
151k
views
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'...
- 3,452
1
vote
2
answers
9k
views
How to use a transformer to power a 5V chip (an Atmega328)?
I am designing an Atmega328 based device which needs to be powered directly from 230V AC. I have found a transformer in my local electronics store which seems perfect, but I have never worked with ...
- 1,045
0
votes
4
answers
1k
views
Dual AC feed to power a DC unit (Raspberry Pi) with Diode and Polyfuse for protection
I wish to place some Raspberry Pi's in remote locations (data centres) for telemetry and other services like serial OOB access.
Typically dual AC feeds are presented to customers in a data centre ...
- 581
6
votes
3
answers
10k
views
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 ...
- 2,116
5
votes
2
answers
6k
views
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 ...
- 38.3k
1
vote
2
answers
10k
views
How can I Build a Full Bridge Rectifier?
For further detail, I plan to extract an alternating current and convert it to direct current. Suppose that the AC flowed through the wires; how can I make it a direct current using the full bridge ...
- 11
9
votes
8
answers
9k
views
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 (...
- 215