Questions tagged [isolated]
The isolated tag has no usage guidance.
68
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Variable linear voltage control using in a flyback converter with UC3843 IC [closed]
I am designing a DC-DC converter with a flyback converter that can be set to a variable output voltage by setting a resistor. Is it possible? I am using a UC3843 IC.
By varying the resistor, we get ...
0
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1
answer
29
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About isolated Power Supply Remote Control Mode
I am using mean well SCW12 series isolated dc dc smps power supply module. The thing that confuses me is the working principle of the r.c pin.
(PowerON: R.C. ~ -Vin > 4VDC or open ; Power OFF: R.C. ...
- 501
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0
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25
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Should there be separate power isolators for CAN and PWM if the PWM driven system is high voltage and noisy?
In this system, suppose the high voltage system does not have isolated ground references. The mcu CAN rx,tx signals and the PWM signal for the HV motor controller are isolated with digital isolators, ...
2
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2
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Is that good application paralleling power copper pours on PCB for heat dissipation and connect with via?
I am using isolated SMPS power module in my PCB layout. I found good examples about layout here. https://www.powerctc.com/en/node/5139.
I have completed routing the isolated SMPS power module from the ...
- 501
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76
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How to use isolated amplifier to measure voltage
I want to read the cell's voltage with a microcontroller, but the cell does not share the same GND with the microcontroller. I want to keep them separate. I read some suggestions for this problem, and ...
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56
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Can I connect the isolated grounds of multiple DC/DC converters together?
I am working on a project that involves using isolated DC/DC converters to power gate driver ICs that will then switch on/off IGBTs. I have 9 DC/DC converters that will power 9 gate drivers each that ...
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76
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What are the correct signal ground connections in an RS485 system with a shared ground on motor drivers?
I'm in the process of designing a motion control system using RS485 and whilst we've generally made things work in the past with a more trial and error approach, in the interest of doing things right ...
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56
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How come I'm not getting the same output at the EAout, with the unity-gain buffer EAOUT output follows the +IN input
The EAout pin does not output the same signal as +IN, the signal is coming from a voltage divider after full bridge rectification
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1
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98
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Using isolated gate driver for switching loads sans MOSFET
I am trying to simplify my circuit and use a single multi channel part for both driving high current MOSFETs and directly driving a much smaller inductive load without a MOSFET basically as a digital ...
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2
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77
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12 V isolated DC-DC converter connection
I have a question about a 12 V to 12 V isolated DC-DC converter.
I am trying to connect a Bluetooth adapter to my old Becker radio, but I got some annoying noise when it was connected. It turned out ...
1
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2
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218
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Decoupling Capacitor DC/DC
What's the physical base of 1nF capacitors (CY) between isolated grounds of DC/DC converters?
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76
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Serial connection of isolated DC/DC supplies
I need isolated 60VDC and I am struggling to get one that can provide enough current (2A is needed). It seems to me serial connection of 4 supplies that deliver 15VDC can be a solution. What can be ...
0
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2
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100
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In what conditions can a DC isolated power supply generate a higher voltage at the flyback transformer's secondary side?
We have designed a passive PoE isolated power supply using a TOP268 converter.
We are converting 48 V DC PoE input to 12 V/1 A output. This 12 V output we are feeding to a step-down power regulator ...
- 11
2
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2
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460
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Flybuck converter at high power
It is said that the flybuck topologies are cheaper than the flyback topologies. This is due to the fact that there is no need to have an optocoupler, the regulation is said to be simpler and probably ...
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1
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89
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Isolated RS485 without specialized IC
I'm looking for replacement for ADM2587E.
This is ADM2587E:
Can I just use cheap, not isolated RS485 transceiver like MAX485 connected to microcontroller TX, RX, DE/_RE via optocouplers and power it ...
- 5,926
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1
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61
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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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267
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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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415
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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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1
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121
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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
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412
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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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29
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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
2
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1
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297
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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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104
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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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243
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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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1k
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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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3
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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
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436
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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
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657
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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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47
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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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378
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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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2
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80
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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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36
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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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2
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76
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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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6
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829
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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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59
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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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383
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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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3
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1k
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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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106
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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
0
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336
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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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1
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336
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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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1
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215
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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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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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249
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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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1
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141
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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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2
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163
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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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1
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101
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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 ...
- 194
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2
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2k
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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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2
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290
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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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1
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487
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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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343
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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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