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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questions with no upvoted or accepted answers
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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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What would be the cause of measuring AC voltage across a LM7805?
This is my first time here so I apologize if I don't provide enough information. I am trying to repair a centrifuge that is giving an error on its LCD display. Though the service manual doesn't say ...
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Reducing AC/DC adapter (SMPS) output voltage
I have a AC/DC adapter P-1650-22 (used to power a notebook) laying around.
I would like to use it for other purposes, i.e. as a constant voltage source for LEDs.
The problem is, that the output ...
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esp32 s2 touch sensor read
I have a problem with capacitive sensor. I have created PCB with 2 capacitive sensors. Everything is working fine and ESP32 s2 mini reading values as I expect while I powering up esp32 with type-c 5v, ...
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3
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Transistor specs in the capacitance multiplier
I'm working on a constant current power supply and as a first step designed the following rectifier with a filter. I know the bottom rectifier is inactive, but with couple of switches the circuit ...
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Powering up an AC-DC power supply under load
Is it safe to power up a AC-DC power supply while it is connected to a load?
Specifically what I'm trying to do is replace an AC espresso water pump with a 24V/2A Brushed DC water pump. Additionally a ...
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2
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Full Bridge Rectifier Schematic Analysis
I am working on a circuit of an old 90's Terminal Applicator and noticed it has AC power coming in, then stepped down with a transformer, and then going to a pair of full bridge rectifiers. One goes ...
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Best placement of bridge rectifier to allow DC/DC convertor to become AC/DC convertor. Does this inhibit surge and EMI performance?
I am trying to use the power supply: CQB50W12-72S12 with AC power without degrading the performance of its recommended filter and surge components. 120VAC peak voltage is 169V and I am worried that ...
user298907
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Step-down conversion materials
I have an ac adapter on which I would like to reduce the output, from 24 vdc to let's say 6 vdc. What type of diodes should I use and how many? What about heat dissipation?
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Power for 1 Device, 1 MCU, and 2 modules
I have four things I need to get power to. The first is a device that needs 48V and 30W. The other three include an MCU and two modules. Each have various pins that need either 3.3V or 1.2V. I’ve ...
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Help in identifying two parts
I need to identify two parts that I need to replace, but I'm having a hard time doing it.
These are the parts:
Part 1:
From my research I think it is a trigger switch (http://www.jiaben.com/en/pro....
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Power supply unit with two negative and positive outputs
So I am trying to add a power supply unit, which takes one input and supposed to provide one output:
IN: 85-265V AC
OUT:12V DC; 25A (max output power 300W)
However, when I look at it, it clearly ...
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How much energy is lost between (solar panels+battery pack) & DC operated electronics due to conversion
For the sake of simplicty;
I have solar panels generating Xvolt, Yamperage.
All of the power will be used by Xvolt devices.
But all of the house and device adapters are designed to use AC grid. So ...
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Need a cheap 24Vac to 12Vdc circuit to test car audio amplifier / equipement
I have inherited from a friend a lot of car speakers, amplifiers and related equipements, 'cause his widow says i'm the only friend with some general interest in this field.
Most of these stuffs are ...
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How to force USB device to drain 500mA Current for charging?
I designed an AC-DC converter circuit(220VAC to 5VDC@700mA) to create a smart phone USB charger.
The Transformer that I used in my design can supply only 700mA current.
I searched the Web and ...
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