Questions tagged [power-supply]
An electronic device which supplies electrical energy to a load. Can be AC or DC input. Typically DC output.
7,302
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AMS1117-3.3 outputs 4.4 V from a 5 V supply
[disclaimer - I am new in DIY and this is the first PCB I designed myself]
I designed a PCB for a very simple ESP8266 12-F + RGB LEDs project.
I assume that I am doing something fundamentally wrong ...
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0answers
30 views
Can I Simulate a SMPS Compensator on Matlab/Simulink
I've designed a type 3 compensator for a full bridge dc-dc converter, I just want to be sure about its stability and want to check its bode plots, I have a open loop model, I can apply pi control on ...
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4answers
86 views
Can I power a 100w amplifier with a 33w PSU?
I purchased a small 2 channel amplifier for a DIY audio project (Amazon link). I'm hoping I can connect it to a power supply I already have to drive a pair of small speakers.
PSU: 19V 1.75A DC (33w?)
...
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4answers
766 views
How to drive 700mA LED cheaply?
I'm new to electronics and am trying to make a night vision circuit. A similar question has been asked before, but with priority on efficiency. I want to control a 700mA-1000mA IR LED using a 5v input ...
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2answers
36 views
BJT Collector-Emitter Breakdown Voltage
I'm developing a flyback converter with the FT838NB1 IC, and I got some doubts about the Collector-Emitter breakdown voltage of the integrated NPN switching transistor.
IC datasheet link: https://...
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1answer
49 views
Protecting unpowered op-amp, or how can I use 12V to switch 3.3V?
I'm designing a Eurorack synthesizer module which includes an MCU, DAC (TI DAC8565), and TL074 op-amp for scaling and buffering the DAC output.
In normal operation the module will operate from a +/-...
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35 views
Power cut when I put my laptop to charge [closed]
I have been noticing for the past few days that as soon as I put my laptop to charge, power goess off in the entire house and returns only after half an hour or something. What could be the reason for ...
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1answer
30 views
How to determine what voltage and current I should use for a Kanthal heating element?
I'm in the process of making a plastic forming "tool".
It has a hot wire inlaid into the top.
I have not come up with the power supply yet but have a few iron core transformers laying around....
0
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1answer
22 views
L298N Module 5V pin behavior on above 12V power supply
I have a lead acid battery that is barely above 12 volts (at 12.6) volts.
This seemed enough to trip the switch in behavior that changes the 5V pin from output to input in the L298N motor driver ...
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1answer
43 views
Bench power supply - Inconsistent voltage output
It's been 3 years since I first bought my bench power supply, a Long wei LW-K3010D. This issue has reoccured to me a couple of months ago, but it usually "went away" when the PSU was ...
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40 views
Power output from a buck boost circuit is too low
Thanks to all who helped on the earlier part of the circuit - that's now fixed and working.
Now the buck boost circuit to drive the LED is working, but it only puts out a very small fraction of the ...
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1answer
19 views
Using DALI-2 BUS interface(slave) to supply SiLABs EFR32xx
I am working on DALI bus converter, using EFR32xx MCU(SiLAbs) for home usage. My question is following.. Is it possible to get DC voltage from DALI interface to supply MCU unit(3.3V) to avoid stuff ...
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15 views
PSRR of buck converter (or boost)
I want to design a power supply based on a line frequency transformer (50 Hz in my case), and provide a stabilized voltage (15 V) after the rectifier (a classic bridge rectifier with tank capacitor).
...
0
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3answers
63 views
High gate pin current leakage on a p channel mosfet
I have added a P-MOSFET before my main circuit, between the v+ of the battery, and the Vcc main power line of the circuit, so that the battery stays disconnected and doesn't drain until I am ready to ...
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0answers
31 views
Need help identifying this SMD
I don't know what this component is. It's found on an adblue ECU for Citroen. I suspect it's faulty and need to order it.
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1answer
35 views
Replacing a NTC in Meanwell Power Supply
I have a query regarding replacing a NTC on a Meanwell dual output power supply. I managed to blow a stepper motor driver and the power supply last night (accidentally swapped a plug to a different ...
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2answers
55 views
How to size overcurrent protection?
I'm a begginer in electronics so I have some very basic questions.
I would like to protect an OpAmp power supply rails from overcurrent. But I don't know at what value I should set this protection.
...
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22 views
Peltier Power supply problem
I am doing a project using a peltier TEC1-12706, however I am stuck on powering up the device. I am using a computer adapter power supply(20V;90W) and I it coupled with a synchronous buck-boost module ...
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37 views
Can I use an Apple charge Cube (5W power) through a Ripcord 9V to USB to feed a Roland SP 404 (2.7 W draw) Safely?
I am asking this as I want to be extra sure this setup does not damage my 404 Sampler as its an expensive item of mine and it's very dear to me so I want to be careful. Here is the scenario:
I have ...
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1answer
51 views
How is it possible for a single power supply of a server to be hot plug?
How is it possible for a single power supply of a server to be hot-plug if it is the server's source of energy? How would the server still be on while the PSU is unninstalled?
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2answers
62 views
How to understand this formula.?
I am having ferrite core T60006-L2063-W517 Ferrite Toroids /Ferrite Rings Core 63x50x25 58.6uH@10kHz.
I wanted to measure inductance of the core from datasheet it shows,
Ferrite Rings Core 63x50x25 58....
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2answers
66 views
Power factor and recitfiers
If I filter the output of a rectifier using an LC circuit on the output, the input source would have a current draw with a square wave shape. I know that a lot of commercial transformers like ...
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2answers
52 views
Understanding stepper motor voltage and torque relationship
The specs of this Stepper Motor say at a voltage of 3.36 V and phase current 2.1 A, the maximum holding torque is 65Ncm. I'm confused though as on the datasheet there is no voltage mentioned, only a ...
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0answers
20 views
Can a faulty TVS diode cause power supply problems?
I have no power feeding the mosfet base with positive signal to switch on the relay that powers the ecu. The mosfet is to the top left above Q111. The TVS is the big SMD next to D100. The fault is ...
0
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1answer
26 views
How to determine the state of charge of a NiCD battery when charged via a Bench PSU?
I’ve a bunch of Sanyo Cadnica cells of various capacities in my possession. Though they are a bit old they have never been used and are NOS. I’m currently trying to charge a KR-FH 7000mAh cell. As per ...
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1answer
26 views
PSU Module for Raspberry Pi Zero
I need to build a small circuit to control some relays where I need to power a Raspberry Pi Zero from mains power using the GPIO pins.
I saw this module: Mean Well IRM-05-5 5VDC 1A 5W.
Is this module ...
0
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1answer
47 views
Drawing power from PoE without Ethernet
I was searching, but was not able to find an answer which is helping me.
This is the first time I'm confronted with implementing something like this, so please excuse if this is a dumb question...
My ...
0
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1answer
50 views
Is powering a 12v DC motor with 11.1 volts a bad idea? (3 * 18560 battaries)
I am working on an Arduino project where I will be controlling 4 individual 12 volt, 0.71 "Direct Current" DC motors, the arduino will be separately powered with another power supply.
I'm ...
15
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3answers
2k views
What is the purpose of transformers on the output side of a DC power suppply?
I have a PSU that plugs into 220-240V AC mains (L&N, no ground) and outputs 9V DC to a single barrel plug.
On the barrel plug side, just about 10cm before it, there's a little box on the cable ...
0
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1answer
44 views
Power Supply stopped working after soldering
I am new to electronic circuits.
I built a basic led circuit on a breadboard to test everything out.It worked as in pictures,but the connections were not stable because the holes were very large.I ...
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4answers
2k views
Differences between oscilloscope, multimeter, and power supply voltage readings
So I recently got myself an oscilloscope and am trying to learn how to use it by starting with the basics, a circuit with a voltage source, and a resistor. When I set my power supply to 5V, the ...
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1answer
35 views
ASUS Laptop A/C Power Supply Output Doubled
My laptop power supply is rated for output to 19.5v, 7.7A.
However, it's kicking out 41.5v. Strange thing is that before I measured this voltage, I have been using it to power on my laptop and it ...
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9answers
2k views
What is the correct supply voltage for LEDs?
I have a 5V supply power, three 5mm red LEDs, and each LED has 47-ohm resistor.
Two LEDs are bright but soon as I connect the third one all of them become dim.
Where am I going wrong? I'm new so a ...
0
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0answers
45 views
My 30A PDU is drawing 20.5A. It's L6-30P plug gets hot (65°C. Ambient: 35°C). Is this safe?
I have a home server setup that is drawing 20.5A from a dedicated 30A line. The power is supplied via a PDU rated for 30A (240V). The PDU's plug runs a bit hot, and I'm nervous if it would be safe to ...
0
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1answer
64 views
Generate a higher-than-power-supply voltage with capacitors
I want to design a circuit which is able to generate 8-10V from a power supply of 5V by chargin parallel caps and switch them to series connection (by using transistors) so they reach the desired ...
8
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4answers
1k views
How much can I push the limits of a device's VDD?
On a PCB I'm designing, I'm using two chips with very similar voltage requirements. Among other voltages, one requires 1.2v, and the other requires 1.1v. in fact, looking at the datasheet, the ...
0
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1answer
62 views
Strange behaviour Raspberry Pi 4
I am powering raspberry Pi using GPIO no 2, 4, and GND as recommended. The Pi only shows RED constantly ON led and does not boot. However, if I connect the USB power source it boots up. The power ...
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1answer
48 views
Constant Current of an XL4016 Buck Power Module [duplicate]
Hi have this buck converter
: Step Down Buck 9A 300W Converter 5-40V To 1.2-35V Power Module XL4016
I've done my research, read some posts and articles but I'm still quite confused, some say a ...
0
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1answer
64 views
In an AC supply why does two single phase 110V wires connected to hot and neutral produces 220V
I have seen people connect 110V to the hot end and 110V to the neutral end of the socket to give a 220V to appliances like refrigerators.
My understanding is that current flows, whenever there is a ...
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0answers
46 views
Mean Well power source doesn't start on battery
I power an amplifier using ADD-55 power source with "built in UPS functionality".
As supposed, it charges a battery connected to "battery" output, and continues to run on it when ...
0
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2answers
48 views
Why does turning on/off one appliance make the other turn on/off on a power board? [closed]
I have a pedestal fan, and an elliptical machine (gym equipment) both connected to the same 4 outlet/port power board. I.e. a board you plug into a single wall socket and now have 4 sockets to plug ...
0
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1answer
68 views
Bench power supplies output
This is maybe a silly question, but when a lab bench power supply has 2 output channels that are both adjustable, can each channel be set at a different voltage than the other?
Like this one provided ...
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0answers
86 views
Bridger rectifier producing non-equal voltages
I am making a bi-polar 12V power supply with a centre tapped (12-0-12) AC transformer. On inspecting the voltages after the bridge rectifier (KBU-4B), the negative side produces -26V and the positive ...
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0answers
38 views
How can I turn off a MOSFET when the temperature rises?
I am using a MOSFET as a pre-regulator.
When the voltage is too high, the temperature of the MOSFET is getting too high. (Even if I take 15 mA current.)
As a safety precaution, if the junction ...
0
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1answer
55 views
Dc to DC converter: “split” one power supply (24V, 5A) into four power sources 5V, max 3A
I have one DC input 24V, 5A.
I have designed a 4 channel led driver using the PAM2804 for Cree RGBW leds.
I am using 3 of them. So, 3 Rgbw leds, and 3 led drivers.
I need to be able to control ...
0
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0answers
46 views
Bridge rectifier overheating
I bought a cheap LED strip with a power supply unit from Aliexpress. After using it for some time I noticed that PSU is overheating in one spot to the point where the label looks burned.
I opened it ...
0
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2answers
60 views
Why is the voltage drop over my MOSFET so large?
I am trying to use an NCV8403B N-channel power MOSFET to control the power for my circuit.
The schematic itself is quite simple:
The MOSFET is controlled by an SPST switch. When in the ON position, ...
0
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1answer
22 views
Vestax PMC-07 Mixer PSU
I'm trying to fix a Vestax PMC-07 Mixer and I'm puzzled by the schematics.
It is fed by a single +12V wall-wart switching adapter through a DC Jack.
Can this configuration really produce a negative ...
0
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1answer
57 views
Capacitor for reducing voltage drops
I use gsm module, which makes current bursts up to 2Amps (maybe slightly more). That causes voltage drops about 0.5V on my power supply (I use lipo battery), and than device hangs up or starts ...
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2answers
1k views
Why have both a Schottky Diode and a MOSFET for reverse voltage protection?
I was looking at this open-source power supply circuit for an automotive CANBus device. I am wondering it would include both a Schottky Diode (D1) and a MOSFET (Q1) on the power supply line. My ...
