Questions tagged [isolated]

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High-current AC-DC converter [closed]

I'm searching for a SMPS circuit with a 220 Vac input and a 12..80 VDC adjustable output. The hardest requirement is the maximum output current must be >20 A. Ideally it would be 80 A.
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Eagle I can not change the isolete value of bottom Ground polygon

well this is my PCB design with Eagle Autodesk. Ground polygon looks perfect with Isolate value 0.8128 [mm] on Top. but this value can not effect bottom polygon Why? How can apply 0.8128 isolate ...
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XL6009 and isolated output

I want to make an isolated DC to AC power supply, with the XL6009 circuit, and I don't know what role "Cdc" have in the circuit. Can I take it off? My power supply is powered at 5v DC and at ...
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HVAC 24VAC backfeed prevention [closed]

I have an HVAC system with a powered open/powered closed supply damper, Ultra-aire 120 V dehumidifier and ventilation damper that is powered to open. I have everything wired up and it is working, ...
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Voltage regulation, 5V +10% to 5V

I'm making an isolated communication/power module PCB, and I came across a problem that the B0505 isolated DC-DC converter has poor output regulation (+15% to -7.5% under load), and my HCS-LSP hall ...
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2 answers
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Can I use common mode power line choke as 1:1 transformer in isolated buck-boost switched mode power supply at 20 - 100 kHz?

I'm planning to build a multi-output power supply that allows output voltages between 0 - 30 V and currents below 5 A. The idea is that I will purchase a number of 30V 5.3A power bricks (unknown if ...
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B2424S-2WR2 supply current

Anyone already use B2424S-2WR2 ? I want connected it with TSR 1-2450 but still confuse will it can supply good current to TSR 1-2450 here the schematic
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2 votes
1 answer
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What is the purpose / function of these bypass capacitors in this Isolated Supply EMC Filtering circuit?

I found this EMC Filtering circuit in the datasheet of the RFB-0505S DC-DC Isolated voltage regulator. What is the purpose of C2 (1nF) and C3 (2.2nF)? I don't understand why they are suggested. Is C3 ...
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Do I need to regulate the output of a forward converter?

I'd like to know if a forward converter will maintain a nominal output on the secondary side. For example if I wind a powdered iron toroidal core with 1:10 turns ratio, the 1 being the primary, and I'...
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Isolated grounding using B2424S-2WR2

Is it possible to isolated grounding using B2424S-2WR2 and supply 5VDC using TSR 1-2450 and 3.3VDC using TSR 1-2433 with below schematic?
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Isolated Current Shunt Amplifier

I have twenty isolated power supplies (around 40 V max) which need to have their current draw sensed and monitored. I'm currently using a TI INA138 current sense amplifier, which sort of works. ...
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Noise from a relay during switching

Is okay to have a load use the same ground as the coil supply of the relay. From my understanding relays do sometimes 'bounce' when switching from N/C to N/O. This inturn can then create some form of ...
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Isolated grounds in power supplies

Can someone assist me with understanding why some power supplies for instance DC to DC power supplies sometimes use more than one ground in their circuit? I have noticed that also some components on ...
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2 answers
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Powering isolated RS485 over CAT6

I'm creating an RS485 network where data and power will be transmitted over a 23AWG CAT6 U/FTP cable. Two twisted pair conductors will be 36V and GND respectively, another twisted pair will carry the ...
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4 answers
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Measuring high voltage with isolated ground

I'm trying to measure the output voltage of a constant current LED driver that ranges from 140VDC to 170VDC. I'm using an STM32 MCU which is powered by a separate external power source to measure the ...
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AMC1200BDUBR Gain is 4 instead of 8

I want to measure grid voltage with AMC1200b. I used a resistor voltage divider and I lowered grid voltage from 110v(rms) to 110mv(rms). I fed the 110mv(rms) signal to AMC1200b (for the first side of ...
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Confusion of the working principle of Isolated SEPIC converter

I am a bit confused about the current flowing in the magnetizing inductance L_m when the switch is off. I am reading a book(Erickson & Maksimovic, Fundamentals of Power Electronics, 2020), ...
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Can C3 in the schematic be polarized?

Here's the data sheet if it helps. https://www.cui.com/product/resource/pdqe15-d.pdf The DC\DC converter is an isolator unit so the left part of the circuit doesn't us a traditional GND, which leads ...
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In the given circuit would CY2 connect the grounds leading to non isolated circuits?

Here's the datasheet for the part being used https://www.cui.com/product/resource/pdqe10-d.pdf I'm using this part to isolate different parts of a circuit. The schematic above is the recommended EMC ...
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flyback RCD design

the equation is used to calculate the power of RCD, I know this power is from leakage inductor the inductor energy can use 1/2Li^2 to express, but I don't know how to get this document equation. Can ...
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Electrically isolate bottom side of a PCB

I have a 4-layer board with no parts on the bottom side, the bottom-side solder mask fully covers all vias. I want to stick the board with a double-side adhesive foil on the metal bottom side of a ...
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1 answer
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Verifying electric brake current with opto-isolated feedback

I would like to find a way to sense (or detect) current through an opto-coupler. This opto is used to power an electromagnetic brake, but depending on the type of brake the current through it can ...
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EMI shielding ground and isolated DC/DC

Given an isolated DC/DC converter, such as Traco TMR4. The GND fill, and internal GND layer(s) would be referenced to the -Vout pin. The TMR4 has an application note showing a fairly typical EMI ...
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AC mains isolated voltage measurement

I am looking for a AC mains voltage measurement circuit for my controller which has to be isolated. There are a lot of circuit using step down transformer, but all of them are too large for my project....
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Isolated dc dc converter

What is the best way (low cost) to obtain a 5v isolated output from 24v batt? The 5v isolated is only for power transceivers so not to much current output is required
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RS485 isolated circuit - forgot connections. Will this work?

below is my schematic for isolated RS485 section. FYI B0305XT-1WR2 is used for power isolation and ISO1500DBQ as transceiver. As you can see I forgot to place GND & GND_RS485 connections at pins 2 ...
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Multiple isolated DC-DC converters in series - ground reference question

I have a question concerning multiple isolated DC-DC converters in series and ground references. I need to measure 48 volts from the input of the first DC-DC converter via a voltage divider, and also ...
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Isolated AC voltage measurement

I'm looking to design a 120-300VAC power meter that uses an isolated DC supply (5VDC to 5VDC by Murata, 5.2kV) with an isolated SPI interface (ADUM4154, optocoupler in the diagram.) The AC line and ...
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RS485 Communication Issue Adm2483

I have Setup like this for my application. I have Transformer which gives out 12V 1A & 5V 500mA output.I have used isolated ADM2483 design where power galvanized isolated. Primary side 5v &gnd ...
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1 vote
1 answer
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Attenuation in the circuitry of differential vs isolated probes

Using this website as a reference for differential probes: https://circuitcellar.com/research-design-hub/high-voltage-differential-probe/ By Andrew Levido, Circuit Cellar The differential probe is ...
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What is the correct way to bias a floating instrumentation amplifier?

Im designing a voltage measurement circuit that needs to measure differential signals in the order of mV in the presence of high voltage common mode noise. Im using a isolated DC/DC converter that is ...
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What is the max current consumption on bus side of isolated RS485?

application - 10 nodes 1 meter apart 120 Ohm terminating resistors at last node and 1st node i hope to use ADM2486 data rate 10-17Mbps vdd1 5V and isolated vdd2 5V what is the max current consumption ...
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What is this transformer, is it package only without coil or complete transformer?

I did a simulation on TI Power Bench for a isolated power supply, There I got transformer spec in BOM, Core=Wurth Elektronik , CoilFormer=Wurth Elektronik Core=150-2340 , CoilFormer=070-4477 Core Type ...
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Does isolated power supplies current draw from one to another if both GNDs are connected to same circuit?

Circuit 1 is powered by (SMPS no 1) = 5V to 8V 700mA isolated dc to dc step up SMPS Circuit 2 is powered by (SMPS no 2) = 5V to 50V 200mA isolated dc to dc step up SMPS application - both power ...
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Isolated Flyback vs Isolated Buck Voltage converter. What are the Pros and Cons?

I am working on a project where I need an isolated power supply. My input is 10-20V and I am looking to get an isolated 3.6V out @ 5A or more. My priorities are easy of implementation, voltage ...
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Coaxial cable in IT Earthing System

We are developing a shipboard system which needs to be connected in a IT network (Unearthed neutral). In order to comply with this scheme we need to avoid negative-grounded, as all the metal ...
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Powering opamp from unregulated DC-DC Converter?

When using one of those unregulated, isolated DC-DC bricks (its output voltage can be as much as a few volts higher than its rating and varies with load) to power an opamp is a voltage regulator a ...
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3 answers
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Is most of non-isolated power supply "safe"?

I need a large power supply (a little over 1kW) for a consumer appliance that only has a single on/off switch and some non-conductive handles. An off-the-shelf isolated supplies run at least $60 for ...
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2 votes
2 answers
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Oscilloscope high impedance ground more noise?

If I setup the two situations in the diagram below one where a scope is connected to the output of an SMPS, and one where a resistor is placed between the grounds of the scope and the supply (which is ...
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How to superimpose a synchronization pulse on a 12V DC power line

I have a 12V DC to DC isolated converter powering a remote display. The DCDC is connected to a 12V supply. I would like to add a 1ms or so pulse on that every second that can be detected by the ...
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Isolated step-down module for powering a Raspberry Pi from a speaker's 12V supply avoiding ground loop and interference

I have an older speaker with an iPod dock that I would like to extend with a Raspberry Pi as a streaming music player. At first, I tried powering the RPi from the dock connector with a Micro USB ...
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3 answers
706 views

The chance of a lightning strike - reduced or increased?

If I connect the receiver and TV body to the earth, does it reduce or increase the chance of lightning strikes the dish antenna?
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Isolated Dc Dc comverter OCP triggers Output OVP on another converter with their inputs connected in parallel and common output ground

In a system we have a bank of isolated dc dc converters that feed a bank of bldc motors with their respective ESCs. These converters have their input connected in parallel to another identical one's ...
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How to measure isolation resistance between floating ground levels?

There a two isolated ground pins on an isolated dc-dc converter . What method is used for measuring isolation resistance between input side ground level and floating (output side) ground level?
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How to control output voltage of DC to DC Step Up Fly Back?

I need to control the output voltage of Isolated Flyback Step-Up power supply using an MCU may be using DAC or PWM or via a digital pot, how to do this? spec Vin 5V - 8V Iout 40mA Vout max 100V ...
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LED PWM with FOD8342 Optocoupler

I'm trying to PWM some high power LEDs from a isolated control line using a FOD8342. It worked on the bench when prototyping, but now it's part of the final design it seems to work for a minute then ...
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How to make a DC to DC step up with multiple isolated outputs? [closed]

I want to design a DC to DC step converter with multiple isolated outputs. I need ten outputs (isolated) positive and GND. Vin: 8 V DC from LiPo battery. Number of isolated outputs: 10 Vout: 50 V, 10 ...
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1 answer
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Isolated Modbus (RS485) ground and UART noise

I build an isolated RS485 (Modbus) interface board for a sensor. I use ADM2682 as transceiver and VAQE6W-Q24-S12-D as isolated DC-DC converter. All is managed my a STM32L412. There is 2 interesting ...
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Is there a RJ45 with magnetics for PHY less network switch

I have a network switch indoor and camera outdoor. I plan on having a PCB with RJ45 with magnetics. Can any tell me how to choose an RJ45 with transformer for a PHY Less network switch.
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Why a double fuse is used in some applications?

In some DC applications in an isolated system (i.e. no grounding), sometimes two fuses are used: one is positioned on the positive (Vcc) line while the other is located on the negative (return path or ...
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