MOSFET TESTING

Started by Jessica Shaw in sci.electronics.basics5 years ago 4 replies

Hi, I am trying to test the following power MOSFET using digital multimeter. http://www.fairchildsemi.com/ds/FD%2FFDL100N50F.pdf I am...

Hi, I am trying to test the following power MOSFET using digital multimeter. http://www.fairchildsemi.com/ds/FD%2FFDL100N50F.pdf I am using the following way to do this http://in.answers.yahoo.com/question/index?qid=20061126230136AA6Blij But this MOSFET is showing anything. Its a new part. I tried another MOSFET (IRF540) and the test worked fine. I think that FDL100N50F has large...


mosfet driver needed for logic-level mosfets?

Started by Anonymous in sci.electronics.basics2 months ago 43 replies

Hello, I've discovered logic-level mosfets, and am using an Arduino to drive a small 12VDC (about an amp or so) pump motor with PWM, using an...

Hello, I've discovered logic-level mosfets, and am using an Arduino to drive a small 12VDC (about an amp or so) pump motor with PWM, using an IRLZ34N as the power mosfet. Would a mosfet-driver be recommended to switch that mosfet on and off more quickly? Or is a logic-level mosfet already designed to efficiently turn on and off with the weak logic level signal? Thanks, Michael


MOSFET: N- or P-, enhance or deplete?

Started by Bob Engelhardt in sci.electronics.basics2 weeks ago 35 replies

Here's really basic question for s.e.BASICS: I want to use a MOSFET to control a load, via a switch. The tricky part is that I need load...

Here's really basic question for s.e.BASICS: I want to use a MOSFET to control a load, via a switch. The tricky part is that I need load current when the switch is open and no current when the switch is closed. What I am confused about is what type of MOSFET to use, and its orientation in the circuit (S & D connected which way?) + | ...


mosfet driver question

Started by Anonymous in sci.electronics.basics11 years ago 3 replies

I'm thinking of getting a TC1427 mosfet driver to power a motor by parallel port. I'm about to place the order, then I thought of a...

I'm thinking of getting a TC1427 mosfet driver to power a motor by parallel port. I'm about to place the order, then I thought of a few questions: Can I drive a 1A load directly from Pin 7 of the TC1427? Or is this a bad idea? For greater loads, the gate of a mosfet (say, IRF530) gets connected to Pin 7, right? Thanks, Michael


markvelectronics.com out of business??? (I bought a Mosfet from them)

Started by Anonymous in sci.electronics.basics10 years ago 1 reply

AF-2 120W-250W MOSFET Power Mono Amplifier ( 6 lbs.) 89.80 114.80 I bought a MOSFET at markvelectronics.com, but the advertised part is still...

AF-2 120W-250W MOSFET Power Mono Amplifier ( 6 lbs.) 89.80 114.80 I bought a MOSFET at markvelectronics.com, but the advertised part is still posted for $89.80. Are they out of business??? ( http://www.markvelectronics.com/store/ ) Its still under warranty (5 years)! Anyone help? Thanks, Miron Cheld


Mosfet as a 12V Switch (and opto)

Started by Prog...@gmail.com in sci.electronics.basics10 years ago 8 replies

I've been stuck on this for awhile. I've got a MOSFET that is not behaving the way I expect. I was hoping it would act similar to the...

I've been stuck on this for awhile. I've got a MOSFET that is not behaving the way I expect. I was hoping it would act similar to the following animation where source to drain is controlled by the gate: http://www-g.eng.cam.ac.uk/mmg/teaching/linearcircuits/mosfet.html But when applying 12V between the source and the drain, my load (a light) slowly illuminates as if a capacitor is power...


P-channel Mosfet switch?

Started by Hammy in sci.electronics.basics9 years ago 11 replies

I'm trying to pull this P-channel mosfet gate to ground (U11). The best I can get is to within 1.1 to 1.2V above ground this only gives...

I'm trying to pull this P-channel mosfet gate to ground (U11). The best I can get is to within 1.1 to 1.2V above ground this only gives a -3.8Vgs. Somehow current is flowing through R27 enough to pull the gate up 1.2V; about 400uA. If the PNP is off where is the current coming from? I'm trying to turn the mosfet off when the 9Vdc source is switched out, but I would also like to get the ...


Basic static electricity question

Started by M. Hamed in sci.electronics.basics2 years ago 8 replies

Let's say I walk over the carpet and get charged to 10KV. Then I touch a MOSFET. Is it fair to assume that the MOSFET won't be damaged unless...

Let's say I walk over the carpet and get charged to 10KV. Then I touch a MOSFET. Is it fair to assume that the MOSFET won't be damaged unless it has a path to ground?


DC motor pwm, mosfet barbecue, etc.

Started by Anonymous in sci.electronics.basics4 years ago 12 replies

Hi, I built a pwm circuit (200 Hz switching frequency) using 12V as a supply, also using around 12V to the gate of an IRF530 mosfet. I tested...

Hi, I built a pwm circuit (200 Hz switching frequency) using 12V as a supply, also using around 12V to the gate of an IRF530 mosfet. I tested it with an automotive turn signal light (about 1 amp) and it worked just fine (without a heat sink on the mosfet). I then tried using it to control a 12V tire inflator/compressor (about 4 amps). The inflator operated fine, but then when I felt the mo...


mosfet gate drive impedance

Started by gearhead in sci.electronics.basics10 years ago 17 replies

I have a situation where I need to use a pretty stiff pull-up resistor on a mosfet gate because I'm going to use a comparator to turn it off,...

I have a situation where I need to use a pretty stiff pull-up resistor on a mosfet gate because I'm going to use a comparator to turn it off, and I plan to limit the current the comparator sinks to about 5 mA. The N-mosfet source will be sitting at 15 volts and the gate drive comes from a voltage doubler. That's a bit less than 30 volts so the pull-up resistor needs to be in the 6k ballpark...


Driving a big LED with a MOSFET

Started by fungus in sci.electronics.basics5 years ago 40 replies

I'm trying to drive a big LED (3W) with a MOSFET. Eventually I want to drive it with an Arduino but so far I'm failing to get the right numbers...

I'm trying to drive a big LED (3W) with a MOSFET. Eventually I want to drive it with an Arduino but so far I'm failing to get the right numbers in my test circuit. My test circuit is like this: +5 | [R1] (8 Ohms) | D G -[R2]--- JUMPER S | LED | GND I can connect the jumper cable to +5V or ground and it switches on/off as expected. My MOSFET is one of th...


TRYING to compare bipolar, Fet and Mosfet transistors

Started by chriswilliams in sci.electronics.basics11 years ago 3 replies

Hi all: I am trying to compare bipolar, FET and Mosfet transistors Could be said that the FET and MOSFET are transistors of a...

Hi all: I am trying to compare bipolar, FET and Mosfet transistors Could be said that the FET and MOSFET are transistors of a greater amplification capacity than the bipolar but they carry out the same one function that is to amplify? In various circuits they seem to be used for the same functions that the bipolar Thanks in advance for any comment


75332P MOSFET drain connected to which battery terminal?

Started by John Doe in sci.electronics.basics6 years ago 11 replies

I have a 75332P MOSFET on a cordless drill controller heatsink. I guess it's part of a pulse width modulator. The drain (flange) connects...

I have a 75332P MOSFET on a cordless drill controller heatsink. I guess it's part of a pulse width modulator. The drain (flange) connects directly to one of the battery terminals. Does the MOSFET drain go directly to the battery minus/ground terminal? Or does it go to the battery plus terminal? Thanks. -- My application... I'm desperately trying to develop a better inline ...


HIgh Current Mosfet Toggle noise issues?

Started by Anonymous in sci.electronics.basics10 years ago 16 replies

Hello, I built a circuit from this link: http://ourworld.compuserve.com/homepages/bill_bowden/page9.htm entitled "High Current Mosfet toggle...

Hello, I built a circuit from this link: http://ourworld.compuserve.com/homepages/bill_bowden/page9.htm entitled "High Current Mosfet toggle switch with debounced push button. It worked perfectly on the breadboard. When I installed it on a pcb board with an external switch (inside an enclosure) the circuit now powers on active. In other words, the IR510 Mosfet has power on the gate pin, ...


hw was mosfet @Bodyeffect

Started by Anonymous in sci.electronics.basics10 years ago

HAi,i want full graphs,formulus,and explination of bodyeffect on mosfet

HAi,i want full graphs,formulus,and explination of bodyeffect on mosfet


MOSFET gate circuit for PWM drive

Started by pimpom in sci.electronics.basics9 years ago 4 replies

Can anyone please explain (or suggest online reading that explain) what factors have to be taken into consideration when driving a power...

Can anyone please explain (or suggest online reading that explain) what factors have to be taken into consideration when driving a power MOSFET with a PWM signal for power control such as motor speed or power supplies, especially at the gate? I understand that a MOSFET gate is essentially an open circuit at low frequencies, but at higher frequencies, capacitive effects modify the nece...


Help understanding N-Channel MOSFET body diode

Started by Anonymous in sci.electronics.basics10 years ago

Is there a rule of thumb stating how much power an N-Channel MOSFET's internal body diode (anode at source cathod at drain) can handle vs. the...

Is there a rule of thumb stating how much power an N-Channel MOSFET's internal body diode (anode at source cathod at drain) can handle vs. the normal use drain to source power rating of the device? Does this make sense? I am using an Nch MOSFET to switch a load to ground in a battery operated project. The design does not allow me to place a rectifier diode in series with the load to pre...


MOSFET ratings

Started by Jon Slaughter in sci.electronics.basics9 years ago 2 replies

Does the current rating of a mosfet take into account all maximum circumstances under normal operating circumstances? e.g., basically if it...

Does the current rating of a mosfet take into account all maximum circumstances under normal operating circumstances? e.g., basically if it says X amps and I run it < 80%X or so will everything be ok? i.e., does it essentially include the power dissipation in that value too(in the sense that P_max = X*Rds_ON)? Just not sure if I actually need to calculate anything else if I'm running


Mosfet

Started by Roger Dewhurst in sci.electronics.basics10 years ago 4 replies

How are the pins of a mosfet identified please. The project requires a 45V/16A Schottky diode or similar. I cannot find a supplier. What is...

How are the pins of a mosfet identified please. The project requires a 45V/16A Schottky diode or similar. I cannot find a supplier. What is special about a Schottky diode? Can I use smaller diodes wired in parallel? R


MOSFET acting weird, any ideas?

Started by Anonymous in sci.electronics.basics9 years ago 7 replies

Hi all! Not a newbie, here, I went to electronics school about a decade ago, and although I've reeducated myself to this point, I seem to be...

Hi all! Not a newbie, here, I went to electronics school about a decade ago, and although I've reeducated myself to this point, I seem to be stuck. Please help, anybody! I've got a mosfet that I'm using, driving an irf510 with a tc4420 cmos driver ic. I've got the driver being fed a square-wave with a 555. The Driver is putting out a clean 12volt p-p SW all the way to the gate leg on the...