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.
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What is the best flyback protection circuit for a 12 V / 30 W solenoid driven by 2 kHz PWM when the diode cannot be placed directly across the coil?
I need some help choosing the best flyback protection circuit for an inductive load driven by PWM. I’ll attach a simplified schematic of my circuit along with test results for each protection method I’...
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Flyback diode solution for inductive loads with GND loss and reverse polarity issues
I'm looking for advice on how to properly design a flyback protection circuit on the PCB for an automotive application, where the supply comes from a vehicle battery and the system must handle GND ...
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Active clamp fly back converter
In this explanation video of active clamp fly back converter , at timestamp 32.45 minutes presenter explains , as switch M1 is turned off , current (I_Lkg) from L_lkg will pass to Cc and magnetizing ...
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Can I use a ceramic capacitor instead of a flyback diode in a motor?
Is it possible to use a capacitor like this (750pF@2000V) to absorb the flyback energy when turning off the motor and protect the rest of the circuit (not shown):
capacitor:
Area of interest:
If so, ...
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Best Topology for 300V - 1500V Input and 220V Output DC
I’m designing a flyback converter with a 1500V max input and ~220V output. The main issue is device limitations: a conventional flyback would need a MOSFET rated above 1500V, but most available ...
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Confusion regarding LT3748 controller operation
Link to datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/lt3748.pdf
Page 8 of the datasheet explains how the control works and what I understand is (and observe from ...
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Does SZNUD3160 really eliminate the need for diode?
From the SZNUD3160 datasheet
Internal Zener Eliminates Need for Free−Wheeling Diode
I am not sure, however, that it is enough. Yes, internal circuitry protects MOSFET itself. But won't the flyback ...
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100 ohms resistor is unintended increase value to Mega ohms after one to several years?
I design a Flyback converter for a PC board or Panel monitor. They consummed about 14W to 20W.
After normally work for years, the 100 ohms at feed back, which is used for limiting current of LED ...
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Selecting a replacement SMPS flyback transformer
I'm trying to repair the PSU in a TV and need to replace the transformer. The part is a YUVA 80GL52P-10-N and the primary winding is open circuit. I've tried searching for a replacement and contacting ...
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Flyback converter on LM5021
I'm asking for help getting a converter based on the LM5021 working. Let me start by saying that I had no previous experience with converters and much preferred digital electronics. I designed the PCB ...
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What is a good flyback diode for a brushed 80mm DC fan?
I have a 80mm DC brushed fan, that has a rated amp draw of 0.18A, at 12V. I am driving it with a LM7812 for positive voltage and switching with a IRLZ44N MOSFET.
I want to make sure this circuit will ...
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Any idea why circuit D would not be recommended for energizing the relay coil?
I am planning on using the G8G-1SV DC24 relay in a product, and for switching relay coils, I always just place a diode in parallel with the coil, to keep current flowing momentarily when the relay is ...
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Flyback - irregular gate pulse due to noise
I am designing a flyback converter, with the following parameters:
Input: 50-60VDC
Output: 150VDC
I use a simple solution using UC3843, TL431, and PC817.
Currently, the circuit is running and has a ...
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TLV431 output voltage for Si3402B PoE SMPS
As I understand reading the TL's datasheet and according to the common sense, a simple divider should provide 2.495V to the TL's ref for the desired output voltage.
For Si3402, there's a AN956 ...
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An old off-line flyback ACDC with strange "standby" function?
I have a t.c. electronic M3000 with SMPS which has a very bad reputation.
For my particular case it has a very weird problem: when device is powered-up (BROWN is ~3.3V, so Q4 is saturated), it works ...
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