Questions tagged [switch-mode-power-supply]
A switch-mode power supply (SMPS) switches been fully-on and fully-off states quickly to maintain voltage regulation. They offer lower power dissipation and run cooler than linear regulators that continually dissipate power through a transistor.
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Basic question - will "universal" SMPS work at any voltage in the range, even DC?
Is it generally true that switch-mode power supplies with wide-input (universal) voltage listed on the nameplate (say, 100V-240V 50/60Hz) will accept any AC or DC input voltage anywhere within the ...
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STM32 based boost converter noise on Rfb
I had designed a boost converter and control its duty cycle using the stm32f446ZE. My boost conveter is designed for 50-312V, 10A. I need feedback voltage but on reading that on oscilloscope I am ...
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Power efficiency between lower voltage BLDC or higher voltage BLDC and no SMPS [closed]
Glossary:
BLDC: Brushless DC motor
SMPS: Switch mode power supply
I was hoping if someone with some DC motor experience can assist me. What would be more power efficient? Going from 15 V to 6 V to ...
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Does the "EMI capacitor" in an isolated SMPS present an additional capacitive load for the primary side switches?
I have recently received an answer to another question (that answer is now deleted unfortunately), for which I would like some clarification. Namely, it described a particular case of isolated SMPS (e....
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Help me to identify these ICs marked 'FA063420', 'FA063360', 'FA063510' [closed]
I detected a malfunction of a driving PCB of mini servo motor "Dsservo RDS3225". Its power controller/PWM IC is (most probably) defective. When I search for the marked code I can't find the ...
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Help me to identify this IC marked '840M1D'
Please can anyone help me to identify this IC (840M1D). The IC is driving a transistor before MOSFET on SMPS.
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Higher capacitance for EMI return cap in isolated DC-DC-SMPS?
A typical SMPS converter usually includes a small capacitor of ~1 nF in tight proximity to the isolation transformer to return the common-mode switch noise to the primary side switch for EMC reasons.
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Wide output range power supply? [closed]
If I want to convert from 270Vdc to a wide output range of 50V to 150V, what are some good controllers and topologies to consider?
Can I design a phase-shifted full bridge that can have this wide of ...
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Power supply failing to start up
I'm trying to diagnose why a power supply isn't working. It tries to start up, and then fails, and repeats.
The power supply is based around the HFC0100 switching controller. It's the power supply to ...
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Feedback network for EGS002 pure sine wave module
I'm lately working on a pure sine wave inverter. Vin=12-24 V, bus voltage is set at 200 V DC.
I have tested the full bridge at 370 V DC max everything works great it's just the feedback part where I ...
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Strange current shape in joule thief
I am using a -26 core material toroid (yellow-white) (from China) in inverting joule thief.
The current at the top suddenly looses/decreases an amplitude.
A diode I am using is Fr102 so for 20 kHz it ...
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LLC halfbridge design startup fault
I have an LLC halfbridge design, using TI's UCC256404 chip, and I'm having a fault declared during initial startup. My primary side aux rail gets bumped up beyond the regulation point, which causes ...
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Input Impedance of a converter and output impedance of battery
It is said that the output impedance of an EMI filter needs to be largely lower than the input impedance of a converter in order to have no stability issues.
From this document written by Christophe ...
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AOZ1284 SMPS - RC snubber needed?
I'm designing an IoT Edge gateway that I intend to take open source. It's essentially a motherboard with a SMPS and various peripherals (ADCs, digital I/O, RS-485, etc.) and hosting an Orange Pi Zero ...
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Smart electronics just died after accidentally disconnecting earth wire in the breaker box [closed]
Recently I've been doing some maintenance work in our workshop that required me to mess around with the wiring inside the breaker box. After I've finished the job, I've flipped the breakers back up, ...
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High frequency noise increasing by current drawn
There are a lot of noise related questions here. Mine may be somewhat different.
I'm using a 24V 2A SMPS power supply bought from market. I've used more than 20 of them.
Some have noiseless output ...
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What precautions do I need to take when measuring 240VAC with a Hantek USB oscilloscope?
I am building a phase angle controller to control 240VAC power. I will need a way to measure the phase shift between input and output for which I am thinking of using my USB oscilloscope. This ...
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Why is the common mode current said to be equal in magnitude for both line and neutral when clearly the path impedances are different?
When I look at the current flow for common mode noise current, I don't see equal impedance between the two paths. I think the equality should be valid only if there are symmetrical paths.
Case 1:
In ...
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Modify SMPS for control with PIC
I'm pretty new in designing things with SMPS, so I want to take an already designed and working circuit, but I want to control the output with a pic, so I can use it for my circuits. Currently I'm ...
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Why am I getting a low output voltage (5.98V instead of 12V) from a LM2623 stepup converter?
I'm working on a project using the LM2623 boost converter, where I aim to achieve a 12V output.
I'm only getting around 5.98V at the output. I've double-checked my circuit and measured the voltage at ...
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Dewalt charger: what is the purpose of zener diode in the primary side controller startup circuit
I've successfully converted two Dewalt battery chargers from 110V to 220V AC input. Success in my case means no smoke coming out and they do charge the batteries. I've got this by just replacing ...
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Estimation of when to prefer ultrafast silicon diodes over silicon Schottky diodes
When comparing "ultrafast" silicon diodes (those with usual recovery times given as either 50 or 75 ns) to silicon Schottky diodes at the same blocking voltage and average current rating, ...
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Space Vector Modulation vs SInusoidal Carrier Based PWM
I wanted to clarify the difference between these two as I think I realized I had a misunderstanding of what each of these schemes incorporated.
In a sinusoidal based PWM you have a reference signal (...
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Undersupplied LM2576 buck-boost converter: Prevention, and where is all the power going?
I had an LM2576 (ADJ variant) lying around and tried building a buck, and then an inverting buck-boost converter, purely for academic purposes. I have next to no prior experience with converters (or ...
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TL431 SMPS Modification is Unstable
I have a 32 V SMPS with a TL431 with an optocoupler as output regulator,
Image Source:https://electrosemic.com/tl431-calculator/
It had 118 kΩ as R1 and 10 kΩ as R2 to create 32 V DC at output.
First ...
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Can a PFC converter work if input AC voltage is distorted (having harmonics)?
I see the assumption that the input AC volatge is clean (pure AC), in almost all PFC explanation articles.
What if the input AC has some harmonics, say a volatge distortion factor of 10%, would it ...
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MT3608 output voltage changing with input voltage
I recently made a small PCB with two MT3608 step-up converters on it, which are powered from a battery. I have two of them. One is for 5V and one for 3.3V.
Here is the problem:
When I power the ...
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Flyback SMPS - Poor efficiency and hot core
I built a flyback SMPS intended to produce ~800 V (variable) from a 12 V input (basic schematic below). I'm using a TL5001 PWM controller with an inverting gate driver, to drive a SiC MOSFET (GeneSiC ...
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PWM buck converter using IRFZ44N and BD139 [closed]
Please help me with this circuit diagram
I need to design a adjustable voltage supply 0-20V.
For that I want to use this circuit but somehow it's not working in my case. the PWM signal was generated ...
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Output Voltage Drop and Insufficient Current Consumption in a Full-Bridge DC/DC Converter
I assembled and tested the circuit shown in the schematic on a copper board. Without any load, I can achieve the desired output voltage of 400V. However, when I connect a 400W load, the output voltage ...
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What are the VDDSD, VLXSD, and VFBSD pins?
On the STM32WB09KEV, and on MCUs in general, what do the VDDSD, VLXSD, and VFBSD pins mean.
I can see that they have something to do with SMPS (input/output, ground and output), but what do they ...
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Why does this push-pull converter fail?
Consider the following circuit of a push-pull converter. I would be interested to learn why you think it fails (MOSFET and controller).
The controller is a UCC28084. The MOSFETs are SSM3K361R (i.e. ...
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Constant output voltage in buck-boost converters
I'm a self-taught student. I'm trying to understand the working principle of buck-boost converters in continuous conduction mode.
When the switch is turned on, the equation describing the inductor is ...
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MOV and resistor selection of smps,flyback converter
I am designing a flyback converter. Input is 60-300 V AC. At the input I am giving a mov and there is a resistor. What is the use of that resistor (10 Ω 2 W)? Will it be acting as a fuse or is it to ...
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How is slope compensation implemented in the UC3843?
I was reading about slope compensation in the datasheet of UC3843 and I have watched this tutorial on youtube which gave me a general idea and overview about what slope compensation is.
Now regarding ...
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Distribute power from one battery to multiple devices
I have a battery, Li-po 3300mAh 22.2V 60C. Then, I have a system (main system, so to speak) which consist of STM32MP1 MPU (operating voltage [1.71, 3.6], typ. 3.3), STA8135GA GNSS IC (operating ...
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Problem on 5l0380R [closed]
I have a sat recever with this power supply. All rectifier diodes burn and replace them and also 5l0380 R was burned and I change it with a new one but it burn. I checked all components around it and ...
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Buck Average Modelling
I completed average modelling with Voreperian PWM switch model as described in Christophe Basso's book "Transfer Function of Switching Converters" and I compared the average model with ...
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How to sample current in high-kHz to low-MHz [closed]
I am working on a project that, at its simplest, is a switching circuit (either a half-bridge or single switch) connected to a resonant filter. I need a way to measure/sample the current going from ...
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Can I deduce the saturation current of a transformer from the rated wattage and maximum frequency?
I have an SMPS transformer EE10, but am not sure about the saturation current it has, I tried doing some internet research, all what I can get is this so far :
I am trying to deduce the saturation ...
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Help me to identify an SMD component marked 'NM' in an SOT-89 package
Identify transistor marked NM:
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What is the mistake in the Current ripple ratio equation?
I was trying to do some research and see some online tutorials to learn designing flyback converter, I have seen this part of that play list , I could deduce some formulas from the video but I had ...
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Input/ Output Impedance of Converter/Input Filter (SIMPLIS)
I'm trying to replicate an impedance plot showing the output impedance of the upstream filter and the input impedance of the downstream converter, but within the sample plot.
Can I get help with:
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Swapping CANH and CANL kills my power converter
I got the first set of these CAN boards I designed and I plugged one into my test setup consisting of a two CAN dev boards as seen below. The first time I plugged my board in I didn't realize I had ...
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Power MOSFET Simetrix simulation using in LLC
I'm trying to model switching losses of an Infineon Power MOSFET (IAUS300N10S5N014) in SIMetrix/SIMPLIS Elements by using in the LLC circuit. But I have some questions.
In the SIMetrix, how should I ...
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Using only ceramic capacitors on an input of an SMPS - unclear advice from manufacturer
I was reading through the datasheet of a boost converter, TPS61023 from TI.
In the "Input Capacitor Selection section", they give the following advice:
Notably, TI advises against using ...
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8 pin SMPS controller chip
I have a 12v 10amp SMPS unit, the main controller ic was damaged and broke apart on removal - hence no markings retrievable.
Is there any way to narrow down to possible matches of the controller chip ...
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Help in identifying SMD SMPS driver chip
please help in identifying this chip (use in 12v 5a SMPS board for a driver LED)
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Average Model of Buck Converter
I am trying to understand average model of Buck Converter for Peak Current Mode Control Topology. Below is a snapshot taken from the Christophe Basso Webpage https://powersimtof.com/Spice.htm, from ...
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