Questions tagged [powermosfet]
The powermosfet tag has no usage guidance.
172
questions
0
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1answer
73 views
Half-bridge gate driver fried, how can I make my design work?
I made a half-bridge following the recommended schematics from the IRS2184 datasheet.
However when I powered it, it triggered over-current and got quite hot.
Here is are schematic and routing.
I ...
1
vote
3answers
92 views
Power sequencing two +5V rails without a voltage drop
I'm new to power sequencing and wanting input on the best way to solve this problem.
I have two separate +5V rails on my PCB coming from a rectified wall source and USB. Due to back powering issues, I ...
0
votes
1answer
87 views
ESP32 grilled with simple MOSFET switch for 12V water pump
I've soldered a small PCB around an ESP32 with following components:
ESP32 Dev v4
Water pump with 12-24V and 4.5-6W rating
Power supply with 12V and 1A rating
Capacitive sensor with analog output
...
1
vote
1answer
50 views
Will replacing MOSFET with a MOSFET with lower rds(on) reduce the thermal characteristics?
I want to replace a MOSFET in a legacy product. The MOSFET is a P-channel Power MOSFET that is used for PWM switching purposes (VGS @ -12V, PWM is 20% @ 200us). The FET is switching in to a 200uH, ...
0
votes
2answers
121 views
Multiplexing 24V signals to DC load generator
(Electronics beginner)
I have a DC load generator (TENMA 72-13210 a rebrand of Korad KEL103).
I want to use if for testing a custom board designed in-house with 30 outputs each capable of driving 10A ...
2
votes
2answers
319 views
How to effectively control a Peltier device with MOSFETs? (general design and heat issue)
First, I'm still quite a novice in the electronics, so may miss some basic knowledge, but trying to learn anyway. That being said, here's my situation:
Goal: Control of the direction of the heat ...
1
vote
3answers
93 views
Using a MOSFET as a relay in mains-powered circuits
I am currently planning a small project where I use a Raspberry Pi as a smart home server to switch loads (mainly door openers & lights).
The usual way would be to use a mechanical relay with ...
0
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0answers
38 views
Boost converter, why the voltage derates when frequency rises?
I am simulating a boost converter in ltspice.
vin=3V, vout_bst=12V, ideal inductor, capacitor, diode and voltage source.
When I use an ideal switch, raising the frequency doesn't affect the output ...
0
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0answers
56 views
Driving Power MOSFET with Optocoupler Problems (Component FOD3182)
simulate this circuit – Schematic created using CircuitLab
So I am trying to build a BLDC motor controller using a Teensy4.0, FOD3182 Optocoupler, and some power mosfets. Currently I am working ...
2
votes
2answers
102 views
Confused on the notation from a TI datasheet
So I'm trying to implement this IC onto a controller that I'm designing: https://www.ti.com/product/UCC5350 I understand for the most part how to apply it, I am just lost on one key part
The specific ...
0
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3answers
40 views
Doubts in using UCC27537 Gate driver to drive IPA60R120P7XKSA1 MOSFET
I want to use UCC27537 gate driver to drive IPA60R120P7XKSA1 MOSFET but I have some doubts.
To avoid voltage oscillations at the gate, do I need to include resistors in between MOSFET and gate-driver?...
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1answer
61 views
Why are p-mosfets preferred in power load-switch circuits
I want to know why p-mosfets are preferred over n-mosfets in power-switch circuits.
0
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3answers
82 views
Understanding these Mosfet Data sheet Specs
So my local electronics store has a catalog of MOSFETS they sell.
I’m having a little trouble interpreting some of the specs.
In particular:
“gate to source cutoff voltage” Where it says 4V MAX, does ...
0
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0answers
25 views
What causes a distortion in the output characteristic at low Vds?
Attached are the output characteristics of two different LDMOS transistors, extracted from TCAD simulation, where Vgs = 3.3V.
The output conductance clarifies the distortion more.
What are the causes ...
0
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0answers
54 views
MOSFET as a switch: operation region during Rise time
In the below picture, during the time period Tri the drain current Id starts increasing linearly wrt gate voltage Vgs and the voltage Vds is clamped to Vd since the drain current hasn't yet taken up ...
0
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0answers
37 views
What will happen if a MOSFET switch circuit is run without the source?
I have a situation where I have to supply the power to the MOSFET gate drive circuit permanently even when the main switch for source battery is turned off. It is because of the fact that the drive ...
0
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0answers
32 views
Controlling DC motor by MOSFET
I am trying to control the speed of a DC motor speed by varying Vds and keeping Vgs constant at 9volts by potentiometer, but I am not getting appropriate and smooth control of the DC motor this way. ...
0
votes
1answer
37 views
What is the difference between an inverting and non-inverting MOSFET Driver?
I'm looking for a High Side MOSFET Driver (have the MIC5014/15 in mind) to drive an N-Channel MOSFET, and I noticed that this IC had a Inverting and Non-Inverting variant. What is the difference ...
1
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0answers
57 views
Getting More Power out of an H-Bridge
tl;dr: how to design an h-bridge to give more power to motors. pre-fab circuits are not an option.
Hi, so for my electronics class we have to build robots from scratch. So no pre-fab circuits (with ...
0
votes
4answers
128 views
What is the general criterion for selecting a MOSFET voltage and current rating?
I've used an N-Channel MOSFET (IRF540) rated at 100V 28A as a switch with a 54V load and current source that maxes out at 20A. The switch worked however, using the load for a while resulted in MOSFET ...
0
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0answers
165 views
Why does MOSFET get damaged when used as a switch in a RF remote control circuit?
simulate this circuit – Schematic created using CircuitLab
Update: The MOSFET gets damaged when not running the motor even once. Maybe even without connecting the motor at all. There is an alarm ...
0
votes
1answer
77 views
N-channel mosfet turn constantly on after a while
Hi;
N-channel mosfet (Q4) work fine for couple of time and suddenly turn on constantly.
I changed Q4 multiple of times and each time it work for couple of time and suddenly turn on constantly.
the ...
0
votes
1answer
70 views
How to connect low power components to high power component?
I have a fairly standard circuit: I am controlling a 12V starter motor + 12V car battery with an Arduino PWM signal. I have an array of 4 MOSFET's to connect the low power circuit (Arduino) to the ...
0
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0answers
35 views
What is wrong with I_drain?
After adding an inductive load at the switching node of the half bridge circuit, the drain current keeps increasing. Why is this so? What have I done wrong in the circuit? I first tried to put L,C,R ...
1
vote
1answer
27 views
Is my circuit to power 38 kHz LED matrix correct?
I'd like to send 38kHz signals to an LED matrix to pulse 5V IR LEDs. The intention is that a lot of IR will be reflected when a finger is placed on a translucent 3mm acrylic panel above the LEDs. The ...
3
votes
1answer
82 views
Help identifying this MOSFET
Trying to figure out what this is, and suitable replacements. Markings are "1 Wt 77" Cannot seem to find anything.
Edit: I removed and sized it today, looks like 2.04 mm square package, ...
1
vote
1answer
64 views
Back-to-Back N-MOSFET inrush current limiting
I try to develop an application where I need to switch 55V at 20A in both directions using MOSFETs.
Because of the high current, I decided to use N-MOSFETs (because they are available with lower rdson)...
2
votes
3answers
171 views
Calculating MOSFET gate current at certain PWM frequency
I want to power the gate of an IRLB3034 MOSFET by a PWM output from an arduino. I know that the current required to charge the gate increases, the higher the switching frequency is. With 5v powering ...
0
votes
1answer
53 views
Multiple devices on a heat sink
I am mounting multiple devices (TO-247) on a large rectangular heat sink. What difference does it make to mount them on the edge of the heat sink vs. the middle?
0
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0answers
36 views
BMS won't output voltage despite good LiPo Cells
I have an 20 cell LiPo battery pack that is healthy at 80V in total, the BMS uses 12 MOSFETs in parallel to switch the negative terminal and they all seem healthy but won't switch on, so I can't get a ...
0
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0answers
22 views
Vgs for MOSFETs in BLDC circuits
I'm confused about how N-channel MOSFETs operate in BLDC circuits.
Say we had MOSFETs that are being driven with Vg = 10V, and DC+ is 36V. Say we have Q1 and Q4 on at some instance (Through phase A ...
4
votes
1answer
205 views
Simulation isn't working for high voltage amplifier
Been trying to simulate on multisim a circuit I saw about high voltage amplifier:
The input is 8 Vp-p and 100Hz and reached to output of 1800 Vp-p and 100Hz.
The publisher mentioned he used the ...
1
vote
1answer
60 views
What is the R-C Feedback to this FET?
I'm studying this RF Power Amplifier and I'm curious about the drain-gate feedback shown as R3 and C6:
What is the purpose of the R-C feedback?
What is this mechanism known as?
0
votes
2answers
53 views
High Power Mosfet
I am developing a DC to DC converter(40V -> 12V) circuit using Mosfet. As I am using solar two panels rated 375 Watts (Max 10Amp,37.5V) each, so the convertor needs to handle 750 Watts at peak. ...
0
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0answers
112 views
Replacement for fnk3070pa
I have a JR1738RX-12V remote control system in my child 4WD car. We noticed that it's too slow/weak so we decided to put 4xRS-570 motors to give it more juice but they are 65W compared 45W from ...
0
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0answers
50 views
How to increase Vdss of power MOSFET?
I want to build a Tesla coil with mains voltage. I found a schematic online but it uses an irfp460n MOSFET which can handle 500v (Vdss) but I only have couple of irfp260n and irf250n MOSFETs with 200v ...
0
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0answers
39 views
Robotics Dual Battery System
Background:
I'm designing a general purpose robotics controller. The controller is split into two boards, a power board, and a computation / data handling board. The controller is intended to be ...
1
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0answers
63 views
How to calculate snubber for switched inductor?
I'm driving inductive load with PWM and my MOSFET can not handle hard switching without reduce dv/dt ramp between drain-source. So I need to add RDC (resistor-diode-capacitor) snubber, but I don't ...
1
vote
3answers
101 views
Level Shifting a MOSFET
I have a high current low voltage MOSFET I'd like to drive with a higher voltage and a micro to reduce power losses through it. I built this circuit based off the typical level shifting designs. The ...
0
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0answers
22 views
MOSFET Selection based on peak drain current
While selecting a MOSFET for application how do we calculate the peak currents which can occur in the circuit?
I am designing a DC/DC interleaved synchronous Buck Converter (2 MOSFETS per rail) for ...
-1
votes
3answers
69 views
Mosfet damage (internal shorting) with zero gate voltage
I am working on a switch for my quadcopter. I designed a basic circuit with MOSFET as the switching device. I am using an LDO to supply the gate voltage to the Mosfet. The circuit diagram is attached ...
0
votes
1answer
59 views
Verifiying what Vgs means
I am looking for a MOSFET that is capable of dealing of a max pulsing voltage of 60A(between drain and source) and came across these 2 MOSFETS
https://www.onsemi.com/pub/Collateral/NDPL070N10B-D.PDF
...
0
votes
1answer
52 views
How to identify duplicate vs original FETs
I am really confused about this topic. Wheather it's ok to use duplicate MOSFETs or not.
Say for example my application requires to handle upto 20 amperes of motor current.
Is it ok to use 100A or ...
0
votes
4answers
839 views
Kelvin Source Terminal on MOSFETs
On MOSFETs with multiple source pins, is the so-called "Kelvin-connected source pin" connected any different internally? Or is it just like every other source pin?
EDIT: Just to be clear, I ...
0
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0answers
73 views
Can anyone help with designing a MOSFET load switch
Can anyone help me design a load switch using the Infeneon IPP120P04P4L p channel MOSFET and the necessary filter components? I would like to use the Texas Instruments ULN2803A darlington driver to ...
1
vote
0answers
42 views
Calculating MOSFET gate current with \$Q_\text{total} = I_\text{gate} \cdot t\$
Hi I am using the MOSFET IRFP4368. I want to use the equation
$$
Q_\text{total} = I_\text{gate} \cdot t
$$
to calculate the required gate current of my MOSFET driver. I have my total \$Q_\text{total}...
0
votes
0answers
19 views
What is the use of epitaxial layer in vertical MOS?
In a vertical MOS(figure below), what is the use of the epitaxial layer?
I understand that this epitaxial layer is a lightly doped n-type layer. Being lightly doped, it will have a high resistance ...
1
vote
1answer
81 views
Need help understanding the mosfet trailing edge Dimming
I am working on a circuit to control AC loads up-to 1.5KW by using Mosfets(FCHD125N65S3R0-F155) Circuit is
I have few concerns
The current is flowing through the body diode of Q2 for positive half ...
2
votes
2answers
203 views
H Bridge runs for few minutes and MOSFETS start smoking
I have created an H bridge as shown in the schematic below.
PWM signal to the MOSFET driver is given by a microcontroller running on 5V.
The MOSFETS are screwed to heat sinks.
To control the motor ...
1
vote
1answer
196 views
MOSFET H-Bridge FAN7388
In this question Fan7388MX on StackExchange, someone asked how to choose the resistor values for FAN7388MX MOSFET driver.
Datasheet: https://eu.mouser.com/datasheet/2/308/FAN7388-D-1805672.pdf
The ...
