Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [flyback]

A flyback diode is a diode used to eliminate flyback, which is the sudden voltage spike seen across an inductive load when its supply voltage is suddenly reduced or removed.

A flyback transformer, also called a line output transformer, is a special type of electrical transformer designed to generate high voltage sawtooth signals at a relatively high frequency.

A flyback diode (sometimes called a snubber diode, freewheeling diode, suppressor diode, suppression diode, clamp diode, or catch diode) is a diode used to eliminate flyback, which is the sudden voltage spike seen across an inductive load when its supply voltage is suddenly reduced or removed.

A flyback transformer (FBT), also called a line output transformer (LOPT), is a special type of electrical transformer. It was initially designed to generate high-voltage sawtooth signals at a relatively high frequency. In modern applications it is used extensively in switched-mode power supplies for both low-voltage (3 V) and high-voltage (over 10 kV) supplies.

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How do we choose a fly-back diode part for inductive loads?

A fly back diode is just a diode that will conduct when the power to inductive load is turned off. My question is, how does one decide on the parameters for the diode so we can choose the correct part? The fly back diode shall be used with DC motor.…
quantum231
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Cascode MOSFETs for high voltage

In this circuit, the HV+ point ranges from 100 to 1200 VDC. The two MOSFETs are rated at 800V, which makes 1.6kV breakdown. D7/D8 are 300V each, so they have a clamping voltage of 600V. My question is: If R7 is "large" there is no low impedance path…
user115094
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Strange Isense shape for my flyback

I have strange shape when I'm measuring Rsense voltage, before that circuit, I have already made a flyback conerter with this SMPS transformer https://docs.rs-online.com/696a/0900766b80107114.pdf and it works however when I make the same circuit…
kodi
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Is there any problem if one of secondary windings is left floating in a flyback converter

Is there any problem if we leave one of the secondaries in a flyback converter floating? I have two secondaries: 24V & 18V. My application needs only 24V. What happens if the 18V winding is left floating?
Imad Kastantin
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Understanding this startup circuit

In the circuit below, how is Q1 turned on? When there's voltage in the bias winding, it turns Q2 On and subsequently turns Q1 off. Also, does the end of R4+R7 keep floating when Q1 is off? It should go to ground. I'd appreciate any help to better…
user115094
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Current flow in a simple flyback topology

I'm continuing my learning about flyback converters, and trying to understand the current flow and the magnetic fields involved. For instance when the mosfet is on current will flow through the primary winding, but since the current flow in the…
confused
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Recommended High Voltage Supply Circuit

Are there any circuit template I could look into if I want to achieve the following specification stated below: Input: 5VDC Output: 1kV, 0.5mA I was looking into the flyback convertor but I am not sure if it will work out. Please help me out.
Kenneth Liew
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"Maximum allowable dead time" in active clamp DCM/BCM flyback converter

I am currently looking into the academic paper "SOFT-SWITCHING ACTIVE-CLAMP FLYBACK MICROINVERTER FOR PV APPLICATIONS" from http://studentsrepo.um.edu.my/8036/7/rasedul.pdf and I am trying to come up with an adapted version of the proposed circuit…
Jenny
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power supply management IC switching transistor - flyback converter

I have a very simple question : is it better to have the switch (transistor) of the flyback converter, Inside the power supply management IC or outside it? or it depend on the application? Thank you for answering my question.
Marouane
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How to calculate auxilary capacitor for flyback

here is my circuit, simulate this circuit – Schematic created using CircuitLab The components try to restart but no results. Vcc output in yellow. I don't find in internet how to calculate Caux and Raux for starting correctly, event when I draw…
kodi
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Sensing the voltage between drain and source in a flyback converter

I want to monitor the voltage between drain and source of the main switch in a flyback converter and use it to control the active clamp switch. Does using resistive voltage divider across the switch make any problem? If so how else is it possible to…
Erfan Mirhoseini
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Is there a way to know if there is a flyback diode?

I have two 12V water pumps that I want to control with an Arduino via a relay. They are generics and I am unable to find a reliable datasheet: Good Pumps with Rohs Motor: Goso GB37-530 Is there anything I can measure to check if they already have…
Carlos Garcia
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PSR Flyback Power supply

From this Reference Design I have two questions: They are doing PSR (Primary Side Regulation) with LM5020. However, according to the datasheet LM5020 is a Current Mode PWM Controller which was not designed for PSR, compared to other controllers…
user115094
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High voltage Flyback transformer polarity

This circuit is a high voltage generator using flyback transformer. It works well, but i thought it shouldn't working by this polarity of the feedback winding ! I mean when the voltage on the primary side increasing(before saturation) the voltage…
M.A.K
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Designing Startup Network for Flyback Controller

I'm trying to design a startup network for this flyback controller, see the picture at the end. I want the controller to start within 10 ms at most. This is what I'm doing: Due to the wide input voltage, I'm connecting the startup network to a…
user115094
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