Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [isolated]

67 questions
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3 answers

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?
Merlin
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3
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2 answers

Design of a low cost/low power Isolated AC/DC SMPS

I am looking to replace a classic 50Hz transformer/rectifier circuit with an SMPS. The input is to be 230VAC (EU) compliant and the output should be 5V/0.2A minimum while 5V/0.5A is a nice to have. An external adapter is not accepted (the apparatus…
le_top
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2 answers

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 power layer of the PCB. The upper layers and the…
Electronx
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2 answers

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 that the compensation is simpler. Nevertheless,…
Jess
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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 from isolated supply? I realize, that it will…
Kamil
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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 not going to create a short circuit between the…
scottc11
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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 voltage. The most common circuit is to use a…
Max
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1 answer

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 described as attenuating the entire common input…
DKNguyen
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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 good idea even if the opamp can handle the higher…
zsky3333
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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 isolated). I notice that the switching spikes/…
zsky3333
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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 will control 9 IGBTs each, so 1:1:1 ratio. The…
Luis
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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 I'm trying to figure out what is the best…
Will Laslett
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2 answers

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 to be a ground loop, so I bought a 12 V to 12 V…
nasty12312345
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Decoupling Capacitor DC/DC

What's the physical base of 1nF capacitors (CY) between isolated grounds of DC/DC converters?
Erick.87
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1 answer

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 possible problems, what passive components would…
Walter Nürnberger
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