Questions tagged [power-supply]
An electronic device which supplies electrical energy to a load. Can be AC or DC input. Typically DC output.
7,085
questions
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Bench Power Supply for ESC and KV on motor
I have a bench power supply it can provide ~10 amps and ~30 volts. Working on an autonomous car project I have an ESC to manage a brush-less motor.
Two questions I cannot seem to wrap my head around:
...
-1
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3answers
25 views
EMI Input filter in SMPS
While reading some application notes and standards about EMI Input filters, and from the fact that:
Engineers are responsible for ensuring that a circuit can operate properly in the presence of ...
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2answers
27 views
Op-Amp Current Consumption
I’m using the LM7321MAX operational amplifier to supply a 12V digital signal from a 5V source. For the op-amp supply voltage: is it better to use something close/equal to my output value (like 12V) or ...
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1answer
58 views
Double wall AC socket with load on one side and power supply
I have on AC socket a load wire on the right side.
I want to connect a power supply with separated load and neutral inputs.
How to handle the case when a plug will be put on the top, next on the ...
0
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1answer
41 views
Choosing AC-AC PSU spec
I am wanting to provide +ve and -ve 12V power rails from a 12 AC PSU using the appropriate rectification, regulators, smoothing caps etc.
The max current draw on the +ve rail is 1300mA and 800mA on ...
1
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1answer
37 views
PWM Motor Driver output voltage is enormously load - dependent
I've built this PWM motor driver (for a motor which requires 5A at maximum 24V and which I want to drive sometimes with 10V and other times at 24V). Here you find the datasheet of the mosfets.
PS: ...
14
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3answers
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PC ATX12VO (12V only) standard - Why does everybody say it has higher efficiency?
To my understandings, the new 12-volt only standard moves the 5V and 3.3V supplies off from the ATX power supply "box" to the motherboard.
According to PC World (which is cited by Wikipedia),...
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0answers
20 views
895 DC Motor powering from lead battery 5Ah
I am going right to a problem: Trying to test my 895 DC Motor (200W) on a lead-acid battery 12V 5Ah. From what I seen on YT, this kind of battery can easily power this kind of motor. But mine just ...
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32 views
Need some suggestion on 220 - 3.3 volt 500 mA power supply (Or 12 volts maximum)
I was planning to make some 220-3.3 volts,5 volts & 12 volts power supplies. I tried the configuration above in proteus (0.47uF, 275 volts RMS, Polypropylene film capacitor in series with a small ...
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1answer
43 views
What is the maximum efficiency for a five volt 555 nixie tube driver
It's less about 555 or nixie tube, but since I am using a 555 to drive a nixie tube, so the question is related since this is a 5v to 170v DC-DC converter with extremely low load, the characteristic ...
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0answers
17 views
What Common Mode Choke choose for EMI filtering at 250v
I'm designing a PCB with a microcontroller that have to handle 3 Relays. The main power source is an AC Inlet socket 250v, the maximum current for all the circuit from this source is 15A (I included a ...
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2answers
58 views
How to improve the accuracy of measured ADC voltage in a circuit connected to Vcc
The question is based on the following setup.
As depicted there is an IC to measure the real value of the 3.3V supply voltage accurately. The measured value of the 3.3V source is transferred via SPI ...
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0answers
36 views
isolated Ground
I have a question regarding the ground connection of two isolated DC-DC converters.
Is the connection advisable considering ground loops? Does it affect the safety?
It is about the circuit seen below. ...
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0answers
16 views
Wiring 18 gauge 2 wire into type C or DC?
I have a Garmin fish finder that requires 12V-18V with 0.5A draw. Since I'm in a kayak I would like to use a light power bank (laptop lithium bank). Bank has 25000 mAh and operates with 2x USB (5V), ...
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0answers
22 views
3.3V LDO alternative using SOC analog output?
I want to build a little adapter board to connect an existing PSOC prototyping board (CY8CKIT-059) to QIIC connector (which is just I2C using JST 4-pin connectors). The QIIC standard calls for 3.3V ...
0
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1answer
44 views
When wiring a 175amp 3Pole breaker
How do I know which is the load side when hooking up a 3 pole 175amp Ac breaker? Both sides look the same and no markings. And what would happen if it was hooked up wrong. Thanks
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32 views
Mini-UPS schematic - load-sharing of battery pack and power source
I am a beginner working on a mini-UPS project for a low-power server (computer).
I've made the following schematic where I'm trying to achieve the following:
Charge 3S 18650 battery pack BMS with 12....
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0answers
51 views
Why is the sensor value at the optocoupler wrong?
I am using six inductive sensors in my circuit. Four of them are working fine, but two sensors are showing very weird behaviour.
I am using an optocoupler to read their output to the MCU for isolation:...
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3answers
64 views
What are the reasons two DC motors with same specifications and running with same power supply run at different speeds?
I am using two DC motors in my circuit.
They are running on same single supply and also using same motor driver but one of them is running slower than the other one.
There is 1.54 volt difference ...
0
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1answer
35 views
What is the 0V reference for MOV's input protection on power supply?
In some application notes for MOVs I see example usage in power supply design where each input line (N, L) from the mains are protected with a MOV to a ground voltage reference (as well as a ...
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0answers
20 views
Why CCTV system fails to turn on ? But SMPS seems to work [closed]
The CCTV camera system fails to start. Already when we have such problem, we are instructed to change the adapter through which we are plugging in. Now, again the CCTV camera fails to start.
So, based ...
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0answers
68 views
Automatic power source selection circuit
I'm working on a project consisting of an ESP32 development board and a breakout PCB. I'd like the project to operate both with and without a USB cable connected to the ESP32.
The ESP32 has an on-...
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0answers
26 views
Preventing power loss with battery backup
I would like to use a battery to power Arduino when the power is out, however I am not sure how to do it.
The first simplest solution that comes to mind is using a usb powerbank, but I am not sure if ...
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0answers
55 views
PSU using -15V and +15V in order to get 30V?
I've been a couple of days looking for an answer, but without much success. I was wondering if I can connect a 30V audio device to the +15V and -15V of a PSU (+15V / GND / -15V)? Or is it preferred to ...
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1answer
46 views
EMI/EMC Simulation using SMPS Software
Assuming I have a complete SMPS simulating circuit using Simplis/Simetrix simulator and all the AC and transient specifications are met. How can I perform an EMI/EMC simulation test using this ...
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1answer
30 views
DIY Bluetooth speaker - Some power related questions
I'm new to electronics and I'm making a DIY Bluetooth speaker. The problem I have is with powering the circuit. I plan to use 2 18650 2200mAh 3.7V lithium-ion batteries in series and use an XL6009 ...
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4answers
63 views
How can a power adapter have higher output current than input?
I have a USB power adapter for a speaker. The specs on it say:
Input: 100-240v-50/60Hz 0.4A
Output: 5V 2000mA
Question:
Isn't 2000mA the same as 2A?
If so, how is that possible?
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1answer
27 views
Inverter resistance and calculation confusion
I'm using a 1200W pure sine wave inverter and a series of extension cords to power devices in a mobile home. When charging my laptop, I noticed it was charging slowly. According to my battery ...
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0answers
50 views
Using 3.7V li ion batteries in series
I'm working on a solar powered project which requires two voltage levels - 3.2v-4v @ 2A for one element an 6v-12v @ 500mA for another.
My initial plan was to use a 12v lead acid battery with a solar ...
0
votes
1answer
58 views
Power factor controller selection
I would like to design a power supply to a micro-controller based system that will need a 12V as Vin and 6A to feed the whole circuit.
The system is expected to be an alarm small equipment.
It is ...
2
votes
4answers
64 views
Starting sequence in PFC AND SMPS Design
In the design of power supplies, we often use Active PFC and downstrem SMPS, to regulate the output voltage, and we often use IC controllers like MC33262 for PFCs and NCP1252 for AC-DC converters. ...
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29 views
Switched power rack panel
Odd question. I have a rack of equipment that I would like to have a dedicated front panel switchable power... switch. Multiple switches on the front panel to turn off equipment individually. There’s ...
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0answers
17 views
Can 85V 35W ballast support a 85V 50W bulb
I am having PHILIPS MPXL DL50/740 85V 50W PX32D but not having a suitable ballast to test it. I am not able to find suitable ballast but ran into a 85V 35W ballast will it support?
Is there any other ...
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votes
1answer
81 views
Inductor - capacitor filter, load disconnected
I'm designing a power supply filter based on inductor - capacitor topology, as shown below.
However, when the load is suddenly disconnected, a high current starts flowing through the capacitor, as ...
0
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1answer
19 views
Powering externally a 3v a 2 relay module
I'm using an ESP8266 to control a dual relay module. As a good practice, and a longer life for the MCU, I wish to power it not using its vcc and ...
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0answers
36 views
Dual output regulator
I have a solar powered project which includes an Arduino Nano and a cellular module.
At the moment the Arduino is powered via the USB port and the cellular module is powered by a small 3.7V battery (...
0
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3answers
36 views
Doubts in using UCC27537 Gate driver to drive IPA60R120P7XKSA1 MOSFET
I want to use UCC27537 gate driver to drive IPA60R120P7XKSA1 MOSFET but I have some doubts.
To avoid voltage oscillations at the gate, do I need to include resistors in between MOSFET and gate-driver?...
4
votes
1answer
103 views
Powering microcontroller with a capacitor
I have a ESP32-SOLO-1 microcontroller mounted on a moving part of a machine which moves in a circle. The idea is to power it with a capacitor and then charge the capacitor in a fixed location when the ...
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0answers
37 views
Why is the angle units of phasor form in degrees and not in radians?
The question below:
The correct answer is "B."
Why isn't also "A" a correct answer?
I tried the numbers in my Classwiz calculator and both gave the same rectangular answer.
Here ...
0
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1answer
27 views
Solid State Relay in NC configuration
Is it possible to build an SSR relay circuit for controlling 240VAC (using TRIAC and other components) with NC configuration?
The idea is to keep the AC circuit closed, even when there are failures in ...
0
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1answer
38 views
What's the system total power factor?
My Answer is as follows:
However, the correct answer is as shown below:
My question is where is my mistake?
So, I added the below as of my understanding is my reasoning accurate or not?
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0answers
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Cold Reset STC125A60S2 PLC Board
I am working on these PLC Board: http://more-suns.com/product/html/?321.html but I cannot contact manufacturer. The fact is to have it programmed I have realized that I can only do it after a cold ...
0
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3answers
59 views
Combining different DC power supplies
I intend to serialise two DC power supplies (12V/16A and 36V/1A) to achieve 48V.
Q1: how much current can I draw from such a combination? 1A, 16A, 17A...?
Q2: I understand that grounds must be ...
0
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1answer
57 views
Adjustable power supply from +5V to -5V
Depending on the orientation of a nulling coil I need an adjustable voltage supply from ~+5V to -5V upto ~200mA. I've tried a few circuits similar to Class AB amplifiers such as the one shown below, ...
0
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1answer
38 views
Reason for using generally TH type current sense resistors in SMPS circuits
I'm investigating SMPS circuits and I'm trying to design my own.
In my design, I have a 300mOhm current sense resistor and its power rating must be minimum 177mW so I need a 500mW resistor. I have ...
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0answers
38 views
Need help with power supply circuit
i'm currently designing a device which uses GSM module. which works on 12V and if the main supply is not there, it will run on battery. right now i'm facing a problem in power supply circuit. i'm ...
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0answers
19 views
ADC power plane confusion
I'm working on an ADC design using the ADC12DL080, but I'm a little confused by the datasheet's recommendations for power planes. The device has a 3.3v analog rail, a 3.3v digital rail (which ...
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0answers
50 views
Lab 30V 10A PSU - no current in CC mode when shorted
I have problem with my PSU, which is similar costruction to Mastech HY3010 (exactly this is MCP lab electronics M10-SP-3010E)
When I short the output, no matter what I set on potentiometers, there's ...
0
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1answer
54 views
Controlling a power supply with a MOSFET
I'm making a circuit that will have a main part (up to 5A load) in a back box, mostly unreachable, and a control panel at the front.
I want to have a kill switch at the front panel, so that I won't ...
0
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1answer
47 views
Power Supplies Total Load
I am a DIY user trying to understand basic electrical knowledge. I’m not sure if I am in the right place to ask so if not, I’m sorry.
I have an LED display screen (see attached photos)that has 4 power ...
