An electronic device which supplies electrical energy to a load. Can be AC or DC input. Typically DC output.

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3
votes
1answer
66 views

How does feedback in power supply work considering output change delay?

I'm designing an SMPS with a PIC microcontroller, but this question applies not only for SMPS but to linear power supply too. I set a desired output voltage in my microntroller and then I perform ...
0
votes
1answer
46 views

Can my dead Lead Acid batteries be reused?

I have two 12V 4.5Ah sealed Lead Acid batteries from an old electric scooter. The scooter is a decade old, and packed up a few months after purchase. The batteries were literally left as is for ...
0
votes
1answer
46 views

Will my 12V power supply ever burn these IR leds blinking at 38kHz even without a resistor?

I'm new to electronics, my background is mostly on the software development side... so go easy on me, as this might be a really stupid question. I just want to be sure what is safe to assume and what ...
0
votes
0answers
40 views

Liquid spill on MacBookPro. How to test magsafe dc-in board? [on hold]

I hope this is a proper place to ask this kind of question... A full glass of champagne was spilled on my MacBookPro model A1278 and took me some time to realize... After 10min, I've turned it ...
0
votes
1answer
43 views

Known voltage/current source

I am working on an EVM for an electricity meter. Its manual says the EVM requires a known voltage and current source for the calibration. I bought a power supply and measure the output of the PSU by ...
0
votes
2answers
50 views

Can you use rectifiers from different transformer sources in parallel?

Consider following circuit: simulate this circuit – Schematic created using CircuitLab It uses two transformers, rectifies their output separately (so that they can't interfere), filters ...
0
votes
2answers
47 views

Powering SMD 5050 strip via LM2596 DC/DC converter

I decided not to order / use the power supply typically sold with SMD 5050 kits. I heard a lot of explosion stories regarding those dodgy stuff. I want to make my own (power supply to drive SMD 5050. ...
3
votes
2answers
126 views

LDO vs switching regulator

We've currently got a PCB that needs to power a modem and a microcontroller. The PCB is powered via a battery (12V - 30V range). The modem and the microcontroller have separate power lines. The ...
-1
votes
1answer
58 views

I am getting a live in my earth of my extension cord socket [on hold]

I am getting a live connection in my earth port of my extension cord socket. I opened up it and I am seeing this. Please help me find what is the issue.
2
votes
2answers
69 views

How to customize the 'write' to instrument?

I'm communicating with Power Supply RIGOL DP832A via Ethernet. ...
1
vote
0answers
58 views

5V DC over data lines

I am prototyping the below diagram and using the following Common Mode Choke from Murata 50475C (4.7mH DCR 0.7R). When I input a signal on U1 Point B 3Mhz D = 50%, I can see AC coupled signal on U2 ...
0
votes
1answer
47 views

12V UPS power supply and battery [on hold]

I'd like to use a Tripp Lite PR40 as a backup 12V UPS by connecting it to a battery before a couple motors in parallel. The battery is 125AH deep cycle AGM. Can I do this? The manual says that the ...
0
votes
1answer
57 views

Supply voltage drops AFTER connecting to device [on hold]

I have a 19V 2.1 amp (power mentioned is 45 watt) laptop adapter connected to a 19V 2 amp laptop (in description power mentioned 10.2 watt). When I plug the adapter, the multimeter shows the rated ...
-2
votes
0answers
64 views

communicate with power supply using python [closed]

We have got RIGOL DP832A in the lab and our task is to communicate it with same using python like to switch it on and off etc etc. can anyone tell me how should I approach to this one? We have to ...
0
votes
4answers
163 views

home socket with DC voltage

I'm wondering why, in a standard house, instead of using many low power AC-DC rectifier, there isn't a big (like 12V 20~50A) AC-DC rectifier which supplies some wall socket with a DC voltage? In the ...
0
votes
3answers
90 views

Ok to use one of the two 12V batteries of a 24V system?

Coach bus with a 24V system of 2x12V 120Ah batteries for aux load. I need 12V for IT stuff. Is it ok to take it from a single battery or is it a bad idea? Right now I have a crappy 12V->24V converter ...
0
votes
2answers
106 views

How to select value of resistor to dicharge a capacitor? [duplicate]

How to set the value of bleeder resistor to dicharge 10kV capacitor, which has capacitance value of \$5\mu\$F?
3
votes
3answers
63 views

Ground noise while using multiple switching regulators

Is there any important points to consider especially about noise when more than one switching regulator is connected into the same ground reference or having a separate ground layer in the pcb is good ...
0
votes
2answers
53 views

Backup Battery for 12V DC Motor

Ok so here's my idea to run backup 12V DC motor power, but I'm stuck on a part of the wiring. 120V AC Plug---> 120V AC to 12V DC Converter---> SPDT Relay (This is where I'm stuck. How would you wire ...
-2
votes
0answers
52 views

Hi I am using inductor on Ground return path, can anybody suggests is there any implications on the ground reference [closed]

Hi I am using inductor on Ground return path, can anybody suggests is there any implications on the ground reference. Any calculations for finding out the Inductor value.
0
votes
2answers
75 views

I am messing around with some power supplies. There are pinouts labelled “reserved” and “remote”- what are they?

I have worked out that that the Remote pin works like the Green "Power Supply On (active low)" wire on an ATX supply, and found a wiki on remote sensing about it being used to get diagnostics on the ...
-5
votes
0answers
48 views

“Battery Ground” message on the annunciator [closed]

I am getting "Battery Ground" message on the annunciator. Where would be the short? All the connections are checked , and they are fine.
1
vote
0answers
74 views

Fried Beaglebone Black - Possible Reasons?

I've fried my beaglebone while powering it from a switching regulator which gives around 4.95V , The output voltage of the regulator was pretty stable with low ripple voltage. What happened was it all ...
0
votes
1answer
49 views

Filtering voltage spikes caused by slow SMPS output regulation

I have a 48V 50A SMPS driving a fairly erratic load. The load varies wildly between 1 and 10A and can suddenly drop from full load to low load. I don't have an oscilloscope at hand, so these are ...
0
votes
3answers
74 views

Method to lower voltage of a laptop charger

I bought an IMAX B6 LiPo Balance charger that needs as input 11-18V but I have an unused laptop charger (the laptop is gone) having 19V with 4.74A. What is the easiest method to lower the voltage to ...
0
votes
1answer
22 views

Raspberry Pi High Voltage Supply Soft Off Circuit

After looking at various designs for a "software" controllable power off circuit for a raspberry Pi computer I decided none of them fit my need so I designed my own. Before I commit it to a PCB for ...
0
votes
2answers
76 views

Power supply with 10 VDC and 2mA

I have device need 10 V DC and 2 mA, can I use DC battery? For example, two batteries with 5 V DC and 1000 mAh?
0
votes
3answers
158 views

How do I get a digital signal from a switch?

I want to essentially drive a relay using a switch. For eg: If the switch (AC Voltage : 220v, 50Hz) is switched on, it sends a digital signal to the relay to switch off.
0
votes
0answers
40 views

110V to 230V converter. What device can I use? [closed]

I'm wondering if I can use an amp designed to work with 110v supply with a 230v supply. The amp says that it is 10 watts. When I search to buy a converter from 230v to 110v, there are a lot of such ...
1
vote
1answer
77 views

24V to 5V DC conversion for Raspberry Pi

I'm trying to power several devices off of a breadboard. For simplicity I want to power these all from the same PSU. The highest voltage amongst the devices is 24V. I was looking to use a 24V 2A ...
2
votes
5answers
140 views

How does the Brita LED work?

Specifically, I'm talking about this product here... Brita Faucet Filter It has an LED that blinks when the water is running. It blinks red, yellow, or green to indicate filter quality (maybe) - but ...
1
vote
2answers
96 views

What is power supply resolution?

In PIC12C5XX programming guide I found a requirement: 1.1 Hardware Requirements The PIC12C5XX requires two programmable power supplies, one for V_DD (2.0V to 6.5V recommended) and one for ...
0
votes
3answers
86 views

How can some USB chargers produce larger total amperage than others?

From a quick survey of wall-mounted USB chargers with more than one USB port, it seems that the total amperage provided, for a given number of ports can vary significantly. For instance, I saw 2-port ...
0
votes
1answer
45 views

12V battery choices (powered LEDs and piezo buzzer)

I need to power two 12 V LED lights (1W - forward current @ 0.083 A) and a small piezo buzzer all in parallel (unsure about the current, tried to measure it with multimeter, but get nothing...). ...
0
votes
0answers
34 views

Run Multiple uCFF Motherboards from a single Power Supply

Warning noob question: I am assembling a cluster of uCFF mother boards that I would like to run from a single (or as few as possible) power supplies. These mbs are designed to use a 19V 3.42A laptop ...
0
votes
2answers
79 views

Charging supercapacitors with Buck converter. Do I need to cut power once charge is reached?

I am trying to build a supercapacitor charger, and as I don't particularly have a good handle on the risks of such a thing, I'm hopping on here to give some information. I am using a buck converter ...
0
votes
4answers
107 views

My thought on the reverse polarity protection

I am now designing a power reverse polarity protection circuit for my system. I found that most methods used for the protection would cause voltage drop in the power path. Even the MOSFET, which has ...
1
vote
3answers
838 views

Doesn't High Voltage Lead to More Power Loss

In India we use electric supply at 230 volts / 50 Hz whereas in US it is 110 V / 60 Hz. Since power loss in an equipment (say resistive heating element) is directly proportional to the voltage, ...
1
vote
1answer
43 views

Where should I place the capacitor in this TL431 + TRIAC crowbar circuit?

I'm building a replacement power supply for my C64 and want to add some protection against overvoltage. For that purpose, I tried to find a suitable crowbar circuit that would short-circuit the supply ...
0
votes
1answer
44 views

Help compare my results to the maximum power transfer theorem and explain using algorithms

So below is an image of the relationship between efficiency of a circuit and the resistance of the load, as you can see the maximum efficiency occurs when the two resistances are equal. here is a ...
1
vote
3answers
55 views

Would having no power supply but a large input signal damage the amplifier?

I am now learning about the power sequence of the circuit. And wonder that as every amplifier has its own limited input voltage (for example: ADA4004's input limit is V− < VIN < V+), would the ...
3
votes
0answers
165 views

What is the name of the cable inside PC cases? [migrated]

Due to limited linguistic and technical knowledge, I do not know (and can not find) the name for the 4 pin (or perhaps 3?) plugs that are used inside PC cases to deliver electricity. My questions: ...
0
votes
1answer
98 views

Running a low voltage stepper motor with a A4988 and 5V power suply

I got this little car I built using two of these motors and A4988 drivers. It was running with a 12V power supply, but I'm trying to get it on a battery and running for about 8 hours. thought I could ...
1
vote
0answers
75 views

Insufficient Power when using one power source vs two [duplicate]

So I've been working on a wireless remote relay switch using several components and have struck a break wall. The issue I'm having is that the D0 siginal output triggers the relay but only at short ...
0
votes
2answers
75 views

How is this 3 VAC power supply charging this 18 VDC battery? [closed]

My cheapo 18V Black and Decker cordless drill recently died, and thinking I could maybe fix it, I took everything apart and then couldn't figure out how it was ever working in the first place! Here's ...
0
votes
1answer
50 views

Control relay from Bluetooth on ATtiny85

I know someone else has made a Bluetooth transmitter to a relay so i wanted to ask a few questions about it being possible? I am an almost newbie at electronics but i do know a few things, so first of ...
4
votes
2answers
375 views

Might swollen caps be working properly? [closed]

I've seen these two swollen caps in a symmetric +12, 0, -12V power supply. The circuit (a theremin) seems to be working properly, but I don't know if that caps are going to cause damage in the ...
0
votes
0answers
76 views

6 Transistor Full Adder

I am working on a 6 Transistor Full Adder whose circuit diagram is The circuit works fine but there is a problem: it needs a 25k resistor at XNOR and SUM point to show the complete Full Adder ...
1
vote
2answers
51 views

Single versus split power supplies for op amps

Application is small signal (low mV). What are the tradeoffs between using a dual supply as opposed to single supply and virtual ground? Apart from maybe the cost of supplying a DC-DC converter to a ...
3
votes
3answers
137 views

Inductor selection for a switching regulator

This is somewhat related to this question, but hopefully a bit broader. I'm selecting components to fill out an lm2734. This regulator will take a 9-12V (11.1V nominal) input down to 5v @ 1A max. ...