Questions tagged [powermosfet]
The powermosfet tag has no usage guidance.
153
questions
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29 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
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1answer
23 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 ...
4
votes
1answer
74 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
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1answer
54 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
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3answers
90 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 ...
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1answer
41 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?
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0answers
26 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
19 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
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1answer
118 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
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1answer
44 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
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2answers
48 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. ...
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0answers
17 views
Current handling capacity IRFZ44
Can IRFZ44 handle 5 amp?
As I am using for switching purpose in DC running light chaser.
I want to connect 60 watt LED module on 12 V battery.
0
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0answers
72 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 ...
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0answers
41 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 ...
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0answers
36 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
55 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
97 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 ...
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0answers
21 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
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3answers
66 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
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1answer
58 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
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1answer
48 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
207 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 ...
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0answers
65 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 ...
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0answers
36 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
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0answers
16 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
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1answer
66 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
149 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
133 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 ...
0
votes
3answers
90 views
How to digitally control a MOSFET? [closed]
I'm trying to make a temperature controller for peltier module using MOSFET. The peltier uses 3.3 to 12 volts and 15A. So far I've only come across a way in which the circuit uses a potentiometer at ...
1
vote
2answers
76 views
MOSFET gets hot in an Op-amp MOSFET-based constant current load build
I've made this schematic following the circuit steps in this site:
and after running the output with just 0.1-1A (which works ok according the input setting and current reading seems correct) but the ...
1
vote
1answer
90 views
Why do bare die chips (MOSFET) have a maximum storage temperature?
As far as I understand, a chip in general and a MOSFET in particular has a maximum operating temperature (letās say 125 Ā°C or 150 Ā°C for Si) because above that temperature the risk increases of ...
2
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2answers
71 views
Oscillations in voltage-controlled current source with MOSFETs and opamp feedback — Why?
I have a circuit that should operate as a voltage-controlled push-pull current driver, able to source or sink at least 2A (into a 1 ohm load). It has unexpected oscillations on the output current.
...
0
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1answer
42 views
P-channel MOSFET switch - very high Rdson
I am trying test my p-channel mosfet (IRF9Z34) high side switch on load. On circuit simulator I get the result I expect, Rdson (VM1) is low and load current is 1.4A. (In the target system the gate ...
1
vote
3answers
52 views
what is causing this ring effect on my MOSFET testing circuit and how would I be able to calculate the MOSFET power losses?
So I have the following circuit
This is the data sheet for the MOSFET enter link description here
Using equations, I worked out what my Rgate to be 2.36 ohms.
where Rtest was a 470ohm ceramic block ...
0
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0answers
133 views
How to simulate double pulse test in LTSPICE and view switching losses
Please how do i simulate double pulse test in LTSPICE and view switching losses like Eon, Eoff as well as power loss.
2
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5answers
274 views
Improving dV/dt turn-on immunity of a mosfet without increasing turn-off time
I'm designing a solid state battery disconnect switch and I want to improve the mosfets' turn-on immunity (high dV/dt on Vds) without impacting the turn-off time. I don't really care about the turn-on ...
0
votes
1answer
56 views
MOSFET Voltage Spikes
I have a voltage source that has a square wave between 20V and 35V with 12.5khz frequency. Even i fully close the MOSFET, it is still conducting in rising and and falling edges of voltage source. How ...
0
votes
1answer
52 views
Electronically Actuated DPDT Switch?
I am trying to be able to dynamically switch two wires on a brushless motor ESC for a Quadcopter. The plan is to wire an arduino to the flight controller so that I can program it to switch the ESC ...
0
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2answers
290 views
Upgrade BLDC motor controller (ESC) to higher wattage (replace mosfets/shunt)
I was wondering if I could upgrade my current bldc motor controller (three phase motor)(*) to a higher wattage/output power by doing the following modifications:
Replace mosfets with higher power ...
0
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0answers
27 views
Awning control for closing
Awning currently controlled by simple 120vac up/down switch and an upper limit switch. Down is stopped by manually flipping switch.
Need to close awning when wind storm occurs. Have an Adafruit ...
1
vote
2answers
287 views
Removing voltage spikes and overshoots using power MOSFET as switch and 555 timer as pulse generator
I'm trying to turn on a power LED using LM555 timer as input signal of IRF630N N-channel power MOSFET as Fig1.
Fig1. pulse generator and switching circuit.
Here is the output of LM555 Timer (Not ...
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0answers
24 views
SIZING steps and Interpreting Mosfet datasheet
After reading those
Interpreting Maximum Power of a MOSFET from the datasheet
How to interpret Vgs(th) min/max in a MOSFET datasheet?
https://www.infineon.com/dgdl/Infineon-...
0
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2answers
43 views
Power MOSFET internal diode: when does it conduct?
So I'm currently studying power MOSFETs and I'm getting a bit confused about when and how it conducts current.
Let's start with the normal MOSFET functioning. I'm considering a n-enhancement type ...
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0answers
75 views
VDS Fault on A4964 BLDC motor Driver
I am actually designing a BLDC motor control unit with the A4964 Driver.
I made the design for working on 24V supply.
I did severals test and HW/SW modification but unfortunaly, the motor won't run ...
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0answers
68 views
Mosfet control Rds on , and Vgs
I want to know how to calculate Vgs , assuming load current Id is constant , Vd = voltage of battery is constant , and fet is operating in thermal stability region , so there is no thermal runnawy , ...
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0answers
40 views
How much does the gate charge of a MOSFET change over lifetime?
Is the total gate charge of a silicon power MOSFET changing over lifetime, as long as it is used inside its rated operation conditions?
I am using a SIHB6N65E (650 V, 600 mOhm) were the datasheet ...
1
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1answer
123 views
High side MOSFET driver with transformer
I am reading the application note " Fundamentals of MOSFET and IGBT Gate Driver Circuits" written by Texas Instrument.
In order to control High Side MOSFET, the application note suggests to use this ...
0
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0answers
38 views
N Channel Power MOSFET as a Switch
I am trying to use a N-Channel Power MOSFET to turn on a capacitor bank in my MRI birdcage coil. I tried using PIN diodes as a switch but they kept failing as they could not handle 400 V and 9 A that ...
1
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2answers
102 views
Isolated MOSFET gate driver VCC and VDD power suppl
I am planning to use UCC21520 for HV SiC MOSFET based full bridge design. My operation frequency would be around 100kHz. I selected UCC21520 in order to achieve the isolation between the power and ...
0
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2answers
159 views
Mosfet Driver IRS2007 failure when running with mosfet IRFB3607
I am designing a BLDC motor controller and facing some issues with using an IRS2007 along with IRFB3607.
For one phase, the high side and low side give clean wave forms as long as V_Pow is ...
