I’m looking to integrate a latching solenoid in my next project. I found a 5V latching type here: LHLA0531111H
The manufacturer recommends I use an H-bridge to control switching of the solenoid. The have a few schematics here.
Instead of using an H-bridge, can I just a use a pair of MOSFESTs to control when it switches? Is that even possible?
why does a MOSFET have higher conduction loss compared to a transistor? While designing switching circuits , driver circuits controlled by a microcontroller, how should i select a switching device(i.e; where should i use a BJT/MOSFET)?
My computer’s motherboard uses all four pin fan connectors with no support for speed controlling the older three pin fan connector. The problem is, all the PC fans that I have use a three pin connector. As fan as I know there are no premade solutions available, so I was thinking of building an adapter that sits in an unused drive bay.
I can’t seem to find much information on how the four pin fan connecter works. Apparently, it looks something like this:
The three pin header is numbered similarly:
Vcc
0V
Tachometer
Could I simply use a logic level MOSFET to do the following?
I have constructed a SEPIC converter which is to be used for maximum power point tracking (MPPT). For simplicity, I am currently just using the hill climbing algorithm with fixed duty cycle steps of 0.01. The MPPT algorithm is implemented in the MSP430F5529 micro-controller and the PWM signal from the MSP430 is fed to a simple driver circuit for the MOSFET. The PWM signal has an ON voltage of 3.3 Volts which is what the MSP430 naturally outputs.
The following is the schematic of the SEPIC and driver circuit.
The input is a solar panel with:
V_oc = 6V
V_mp = 5V
I_sc = 0.67A
I_mp = 0.6A
Thus, the nominal output power should be around 3 Watts. The output is simply a 22 ohm resistor.
The FQP30N06L power MOSFET is currently being used on the switch and it is being switched at 50kHz. Now comes the main issue and the reason I am posting this question – During operation at duty cycles at around 0.35-0.5, the MOSFET gets unusually hot – At least 70 degrees celcius in a room temperature environment. On the other hand, I did measure the waveform of both the gate voltage V_GS and the switch voltage V_DS as shown in the figures below.
I did notice that the beginning of the pulses of the switch voltage V_DS has some unusually high peaks but I am not sure what these are. Perhaps someone could also point out why these peaks occur.
So what could possibly cause the MOSFET to become so hot and hence cause my converter to be very inefficient?
I recently came across an article explaining how to drive a high side MOSFET using a “separate isolated power supply whose ground and the ground of the MOSFET-based circuit are isolated”. However after reading this article I still do not completely understand the driver circuit and had a number of questions:
The circuit suggested by the this article is below:
I’ve made a simple charger out of 4 TP4056 modules and 4 18650 sockets. These modules have overcharge, undercharge and overcurrent protection included, but I also want to know how simple it would be to make it also reverse-polarity protected since that condition is much more likely as the above 3 combined, given that I’ll swap batteries often and am bound to be mistaken once in a while. I’ll also likely build some chargers for other people for their needs and this could be a nice feature. Could I just use the MOSFET trick to make reverse polarity protection for the charger or is there something I’m missing?
the below circuit triggers with 0.05 volt, even if touched the base of 2N3906 the circuit triggers ,
what is the issue or alteration to be done to fix the circuit to work only at 0.5volt or higher is applied on the signal pin.
Guys i was going through basic gain cell topic in my textbook. I came accross this circuit. Pls explain how vo is not equal to VDD. I mean how can they be different? There is no resistance that there will be a voltage drop. There is only a current source. Does voltage drop occur through current sources also? In book it says vo will be determined from feedback.
in this circuit:
simulate this circuit – Schematic created using CircuitLab
is it possible to measure resistance between drain and source if no motor(inductance) is connected or do the diode/capacitor falsify results?
assuming the gate still carries a charge after being connected to a power supply, do i need to connect it to a power supply ground to get rid of the charge or just shorten source and gate?
can there be a charge at all or will R1 (1MOhm) take care of that?
How do you change the pin ordering of a P-channel mosfet in Fritzing?
I’m trying to place a generic P-channel mosfet, to represent a ZVP2106A. However, Fritzing’s part has a GDS pinout, whereas the ZVP2106A has a DGS pinout. There doesn’t seem to be any pinout configurability in Fritzing’s part selection panel, and even the “Part Editor” doesn’t seem to allow me to edit the part’s pin ordering. Is this supported in Fritzing?
I am designing a H-Bridge using IRLZ44N MOSFETs, IR2104 driver ICs and UF5401 diodes.
The current circuit looks like this:
It will be used on a battery powered device, so no real grounding available, the casing will be plastic or close to nothing.
The only place a human could touch is the motor terminals and the power connector.
I have read in many questions that proper ESD protection is very important and such components are very sensitive, but even so I am confused as most H-bridge tutorials don’t include anything about being ESD-safe.
TL;DR: Do I need additional protection for the average use case with these components?
how to find region of operation of MOSFET in a circuit in ngspice? or how do you know that a MOSFET is in saturation in a circuit in ngspice?
I’ve been trying to get into some low level electronics to explore to “Internet of Things” and still struggling a little with MOSFETS.
I’m trying to make a single push button act as a latching power switch for a microcontroller, then act as an input button when the mc has powered up
(further details in my previous question).
Following the suggestion to use a BSS84, I discovered the mircocontroller I’m using (ESP8266 ESP-12) draws a current of around 300mA and, looking at the datasheet for the BSS84, I saw the continuous current draw is -0.13A?
This is where I get confused a little. I understand the continuous draw needs to be adequate (130mA is too low) but why is it +/-?
Does the current not flow from Drain to Source? If so how can there be +/- voltages? (I realise I may have a very poor understanding of FETS)
Goal
I’m aiming to use a logic level mosfet to provide at least 300mA when the gate is connected to ground. Would something like the IRLML5103TRPBF work or are there better options?
Thanks in advance for your help. Apologies if I’ve got entirely the wrong idea and sounds like a crazy person ha!
I am trying to design an H-bridge inverter to supply maximum current to my coils. I need to supply as much current as possible so that I can make a electromagnet whose polarity constantly flips so that i can levitate a moving Halbach array over top of those coils.
I’ve tried a number of things to make my mosfets as efficient as possible but when I enter in my Rds values into PSIM the current drops to 4mA. I have a DC power supply capable of outputting 18V and 10A.
when I run the simulation I get that the current is through the coil is only 4mA which is nowhere near enough, I’m not sure if I am simulating something incorrectly or if thats correct based on the way the circuit is designed. Does anyone know how to maximize the current the coil? also even with the RC snubber circuit my MOSFETS are heating up alot! is there a better way to reduce that? My PWM frequency is at 120Hz from an arduino, and its a 40% duty cycle.
My coils have 220 turns and are 18 gauge wire, with a radius of 2cm and a length of 2.5cm, they are air coils I dont have any core.
My mosfets are
FQP27P06
FQP30N06L
Thanks in Advance
EDIT
After fixing the orientation of the PMOS my output looks good.
However I’m finding that the magnetic field produced through these coils is not strong enough to levitate my pod. Is there something I can do to make this stronger?
EDIT2
simulate this circuit – Schematic created using CircuitLab
For a circuit such as this, people have suggested on this site, to add a zener diode to prevent the MOSFET from blowing up by protecting against gate overvoltage. I want to know that: if the voltage at the gate is 12V or 0V, then what could be the possible reasons of overvoltage?
I need to control 30 high Current LED’s, the issue is I don’t want to have 30 MOSFETs, is there any way around this dilemma? any help will be appreciated, I am aware of the CSD17313Q2, but not sure if it has separated outputs, it appears to have 2 gate pins?
I’m not quite sure what to do with the BSIM packages: http://www-device.eecs.berkeley.edu/bsim/
The package has basically benchmarks and source code.
As for the source code part, if I just want to do simulations of IGFETs, then I don’t need to compile it, right? That’s only for guys developing electronic simulator software… It’s either the electronics simulator I’m using already supports BSIM 1, 2, 3, 4 or not, correct? You just have to feed the model card.
And then, the benchmark is just for testing BSIM compliance?
I designed this circuit to switch on my P channel mosfet because the Vgs will be more than -20 V (maximum Vgs) if I put the traditional design .
Is this circuit correct or can you help me to improve it more?
thank you .
To provide an adjustable, switchable reference voltage the the xVREF input (Iref -3uA to 3uA) of the current control of a DRV8825 stepper motor driver allowing to reduce power during stand still, I tried the following circuit:
As expected, I can for example switch between 1V and 260mV allowing to reduce motor current from 1A to about a quarter, still being able to adjust the current.
I’m just unsure if this is a good design?
While looking for MOSFET Drivers I locked on to IRS20124s but I could only get IR2104 from the market. I am not sure how to drive my MOSFETs using IR2104.
I have already developed the circuit generating PWM Wave.