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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Is this circuit safe to put in my ceiling? What improvements could I make?
I uploaded a picture, is there a better way for me to share the circuit?
The addressable LEDs use up to 100 mA at 5 V, that is why I am using three 5 V power supplies in parallel, each offering 600 mA....
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AC-to-DC rectifier and DC-to-DC converter
I am currently doing an assignment featuring an AC-DC EV Charger topology as shown below.
I have obtained answers for (a) and (b). However, I am unable to derive the equation exactly as given in the ...
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What are these resistors used in this flyback converter?
I'm new to designing flyback converters. I noticed resistors connecting the primary and auxillary coils. Can somebody explain the usage of these resistors for me.
The IC in this schematic is a CR1510. ...
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Ground connection of power converter and MCU
I've designed an AC/DC power converter PCB, with input, and output voltage sensing, but I have problem connecting it to microcontroller board, i'm using F28379D launchpad as the microcontroller.
I ...
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How should I come up with a power supply for 5 motors, one micro-controller (ESP32) and one microprocessor (Jetson Nano) for an object sorting arm
I am trying to design a power supply for a robotic arm with 5 servo motors(2 are MG90S and 3 1501MG motors). I'm planning to use an ESP32 microcontroller and Jetson Nano.
I have the option of using ...
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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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Verify the correctness of a circuit: AC to DC conversion for Arduino Nano and relays
I need your opinion about the correctness of my circuit. As is shown in the drawing schematic, the circuit is supplied by 220 VAC which will be converted to 12 VDC. This output is used to supply the ...
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LTspice AC/DC converter with DC/DC boost converter
So this is my first time using LTspice and I need to convert my (AC) Vin 11.5V to DC and then boost DC voltage to Vout 22.5V. I have a few givens and some I needed to calculate. I am struggling to ...
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DC-DC design with STUSB4761
I am designing a powered USB HUB (UFP) which can provide power to the host through USB PD. This means I need a PD controller which supports DR_Swap and it seems that STUSB4700/STUSB4710 cannot be used ...
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Understand firing angle chart in dual converter
How to understand below Firing Angle Chart,
I guess the y axis should be voltage of the source, but what is the x axis, why a1/a2 points right, the location of 0⁰/90⁰/180⁰ seems quite strange.
Hints ...
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How can an AC adapter push 11A but only suck 2A?
I have a laptop adapter that takes in 120V AC and converts it to 20V DC. The adapter is rated for 230W (11.5A 20V.) Knowing conservation of energy and such, this means that the adapter takes in 120V ...
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Calculating input power of ACDC power supply
I'm trying to calculate the input power draw of an ACDC power supply that we are using in a control chassis and am confused by what to me looks like conflicting information in the datasheet.
The power ...
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Ground connections around bridge rectifier in flyback converter
I am designing a flyback converter and I am being told to make the ground net connections as shown in the image below.
I think this is colossally dumb because it eliminates PRI and SEC isolation. I ...
user224284
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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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Seeking a good solution for mitigating the effects of high in-rush current caused by an AC-DC converter [closed]
Many AC-DC power supplies (say, 220VAC to 24VDC) have huge inrush current values. For example, a device might have an inrush current of 80A@230VAC. This raises the question of how to handle the ...
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NiMH battery charging problem
I have a battery (8 cells in series, NiMH AA cells (1.2 V to 1.3 V), 1300 mAh per cell).
Cells used-
https://www.amazon.in/Rechargeable-NiMH-2300-Peak-Power/dp/B01MF8HUKO
https://www.amazon.in/...
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Is there a 3-phase to DC converter that draws current proportional to voltage?
Of course, 3-phase alternating current can be converted into a rippling direct current with a 3-phase bridge rectifier.
This design only draws current from the two phases with the most voltage ...
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What AC/DC adapter do I need to power 10 high-power (3W) LEDs?
I'm attempting to build a near-infrared (850 nm) lamp using high-power LEDs and am struggling to design a suitable way to power them directly from the AC power plug (220V).
I have 10 high-power LEDs ...
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Which power source is good for my project?
I want to create an inverter LED light source. I would be using 2 COB LED lights rated at 4 volt DC, 8 watt. My idea is that when the phase is connected, I want the light to glow and at the same time ...
user357345
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Single Phase Active PWM Rectifier using MOSFET
I am using this H-Bridge Configuration to make active PWM rectification to control the output average Voltage by controlling the Modulation Index.
Here is the circuit diagram and the pulses of each ...
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AC and DC inputs to a Power Supply
I am studying about power supplies and I need some help with the following. I have a power supply with a 12 V DC output to power the lower power controller electronics. This power supply has two ...
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How does an AFE boost voltage?
I have an active front end unit that is connected to a 3 phase system. It's controlled via software and I can set a value for the DC bus voltage.
When the input is the AC 3-phase, how does this ...
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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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How to convert 240 V single phase to 300 A 12 V DC
Residential situation with mounted 2-ton hydraulic 12 V crane.
Have 120/240 available, need to create 12 V 300 A available power for intermittent use, boat launch. Average power used 150 A 12 V DC, ...
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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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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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Flyback converter MOSFET driver
I am building a flyback converter to convert 230V AC to 20V DC using a microcontroller. So far my simple converter works, but I have to power the MOSFET driver such as HCPL-3101 from a secondary DC ...
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How are modern ACDC power supplies desgined?
I wonder about how exactly modern, but mundane ACDC power supplies (your phone power supply) are designed. Maybe my misunderstanding comes from one of the following assumptions:
Modern AC-DCs ...
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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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PCB inside metal chassis. Is chassis ground required?
I have a project that has a PCB housed in a metal enclosure. The PCB is powered by a USB-C connector. Power input is 20 V DC @ 4 A max. Power is sourced from an isolated AC/DC wall wart adapter. The ...
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UL ratings and power supplies (DC transformer)
I read somewhere that if you sell a product that you plan to be UL certified, this means its power supply must be UL certified as well.
This means that if you supply power via a transformer (external ...
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ATX Computer Power Supply Spark in Non-computer Application [closed]
I would like to ask for your assistance with using a Silverstone DA1650 Gold computer power supply (you can find more about it here: Silverstone DA1650 Gold) for a non-computer application. In this ...
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Safely run a pump using the driver/controller built into an air conditioner - switch EMC motor for a pump motor
I am attempting to switch an ultra-efficient household air conditioner from air cooled to liquid cooled. The unit, (LG DUALCOOL with Watt Control-Eco - T06EV4), was attractive because it has 3 power ...
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AC adapter interfering with WS2812B LED strip
I have 2 power adaptors connected on same AC line, both grounded.
Power adapter 1:
12V DC 10 A for powering 12 V LED strips, controlled by ESP8266, IRLZ44N MOSFET used to control brightness of the LED ...
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Is an AC/DC converter with no visible fuse before the transformer inherently dangerous?
I've been using a generic, unregulated mains AC/DC converter (wall-wart) for a very low-power project. It's output was a bit prone to 50 Hz ripple, so I opened it up to investigate how the circuit ...
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DC appliances running on AC system [duplicate]
How do DC ran appliances work in an AC electrical system? For example, a house runs on AC, but the microwave runs on DC. How exactly is AC converted to DC? Does that DC power then have to invert back ...
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Is there any benefit to converting from single to 3 phase AC before a DC conversion?
Compared to single phase, 3 phase AC produces less ripple in the resulting DC waveform when rectified. At the capacitor filtering stage, it is much cleaner with less sag than filtered DC converted ...
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Trying to fix a mess with DC Power supply
I am not even close to know what I am doing with the electricity, but I have a power supply of my 8 cameras that is gone bad and I think I can manage to replace it myself, but there is a big BUT here. ...
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Should consumer electronics have low voltage isolation?
I am making a MCU (PIC12) controlled 230V relay system. They will be operated from 230V mains. Should I use isolation (1:1 transformer?). I would use this converter for 230VAC-5VDC (or something like ...
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AC-DC Schematic - Is this a Death Capacitor [closed]
Is this a death cap? I think it's not a death cap because it doesn't connect to the DC ground, but I'm not 100% sure.
Image Source: Hi-Link HLK-20M24 Datasheet - https://www.rhydolabz.com/documents/...
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Why aren't I getting a voltage reading from my AC/DC power adapter
I am new to electrical engineering.
I cut the barrel jack off the end of a 24V DC power adapter, exposing a red and white wire. I'm trying to determine the polarity of the red and white wires with a ...
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Non Fused AC Rated Disconnect Switche for DC System
I have 110VDC supplied by a controller to power a actuator/motor located in a hazardous C1D1 environment. I wish to install a disconnect downstream of the controller in the hazardous location so the ...
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Predicting health of power supplies
I have a couple of 12 V, 1200 mA wall mount power supplies.
Currently, using a digital multi-meter, I am able to measure good voltage and amps coming out of some power supplies.
Since these are ...
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Why do photodiode transimpedance amplifiers care about signal frequency?
I'm designing a circuit to amplify low light levels (in the range of 0.1 uW) of measured black body radiation for application in a pyrometer. I don't have much experience with this kind of stuff so I'...
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What fire tests are done on power adapters/chargers?
I was curious about the fire risks in using a typical AC-to-DC wall adapter
(e.g., this)
and went to the UL website
to learn what exact tests were done to get the "UL LISTED" stamp,
but I ...
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Variable input 208V-600V AC to 24V DC without transformer
The Question:
How can I design a circuit for an automatic transfer switch that accepts 120V-600VAC and keeps some 24V batteries charged (long term trickle charge is fine). P.S. I would like to keep ...
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What damage or reduced performance would result from giving 120 V, 60 Hz AC power to a 115 V, 400 Hz AC/DC rectifier?
This is part of a larger project, and is one sub-question related to a higher-level question I've asked on Reverse Engineering. You may find useful background information there.
I have a controller ...
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My AC-DC PFC rectifier self-boosts voltage when with no load
I have made a PFC IC LT1249 reference design - a few differences are 820 uH inductor, 1.1 mF capacitor and different MOSFET.
When I connect AC (50 V) with no control (17 V) voltage the DC output rises ...
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Reusing a HP laptop charger of 3 wires (logic inside)
I have an HP laptop charger 18.5v 3.5A (1X2057... WBGST0A...)
In the past the charger was working fine and I removed the tip for an experiment, so I can't check wires measuring the original tip.
Wires ...
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SMPS for AC-DC conversion
The question is related to datasheet of part DK1203.
The datasheet description is as follows:
The DK1203 is a secondary side flyback type AC-DC Switch Mode Power Controlling IC. With integrated 700V ...
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