"Jellybean" HV low power MOSFET

Started by Ralph Barone in sci.electronics.design5 years ago 8 replies

Can anybody suggest a cheap, easily obtainable > = 400 V, < 2A thru hole MOSFET, preferably one that's designed more for analog use than for...

Can anybody suggest a cheap, easily obtainable > = 400 V, < 2A thru hole MOSFET, preferably one that's designed more for analog use than for sub-ns switching. Thanks. I'm looking to squeeze a cathode follower into an existing vacuum tube amp and adding one MOSFET is easier than adding half a 12AT7.


JFET vs MOSFET

Started by Anonymous in sci.electronics.design4 years ago 38 replies

I am mostly an RF engineer , but our analog guy moved on and I am doing a little bit of sustaining of his stuff. In looking at one of his...

I am mostly an RF engineer , but our analog guy moved on and I am doing a little bit of sustaining of his stuff. In looking at one of his circuits I have gone back to the basics on JFET and MOSFETS. I am seeing that the basic electrical characteristics of a depletion MOSFET is similar to a JFET (I see the difference in enhancement MOSFET - ie - they are generally in an off state a


MOSFET specs

Started by Sylvia Else in sci.electronics.design3 years ago 11 replies

I was looking for a high voltage MOSFET with a low drain source resistance. I was considering...

I was looking for a high voltage MOSFET with a low drain source resistance. I was considering this: http://au.rs-online.com/web/p/mosfet-transistors/8647925/ I cannot reconcile the information given there. Figure 3 indicates that at 25 degrees, an Id of 5.5 amps and Vgs of 10V will give an Rds of about 320 milliohms. So go to Figure 8, and for the same conditions it gives an Rds of ...


How about it? Experiments of the third kind , take 999999.

Started by Jan Panteltje in sci.electronics.design8 years ago 19 replies

How about it? Experiments of the third kind , take 999999. Update Hotplate design, stabilizing the heater MOSFET ...

How about it? Experiments of the third kind , take 999999. Update Hotplate design, stabilizing the heater MOSFET http://panteltje.com/pub/thermos_box_mounting_plus_heater_circuit_diagram_IMG_3415.JPG shows the quick sketch diagram of the MOSFET driver. The idea is that the current through the MOSFET is exactly proportional to the input voltage. As we all know, MOSFETs like to do t...


"high voltage" MOSFET

Started by bitrex in sci.electronics.design5 months ago 20 replies

Looking for a MOSFET with a 100 or 150-200 (would be better), Vds N-channel that can switch a couple amps at a couple MHz, preferably in D-pak...

Looking for a MOSFET with a 100 or 150-200 (would be better), Vds N-channel that can switch a couple amps at a couple MHz, preferably in D-pak or something for ease of compact Manhattan-prototyping. MOSFET-selection is always problematic for me there are so many and the parameters like temperature de-rating and how fast you can switch it at a given temperature all interact so it's hard ...


A quiet forward converter likes only one MOSFET -- why?

Started by Piotr Wyderski in sci.electronics.design7 months ago 18 replies

Hi, I have been trying to build a low-power multiple-output converter that has no regulation at the secondary side. Its purpose is to power...

Hi, I have been trying to build a low-power multiple-output converter that has no regulation at the secondary side. Its purpose is to power many floating MOSFET drivers, so a reasonably too low voltage is not a problem, but to high certainly is. Particularly, the experiments involved powering a mock-up SiC MOSFET driver with +15/-3.3V rails. Therefore, the smoothness of the transition ...


strange MOSFET failure mode

Started by Winfield Hill in sci.electronics.design4 years ago 10 replies

The subject MOSFET is a C2M0280120D, a serious 1.2kV SiC TO-247 MOSFET. The scope pic shows driving it with a -3.6 to +16.5V gate pulse, ...

The subject MOSFET is a C2M0280120D, a serious 1.2kV SiC TO-247 MOSFET. The scope pic shows driving it with a -3.6 to +16.5V gate pulse, 100ns long in this case, and it's switching a 50-ohm resistor from +200V, or 4A (part of my fast HV pulser project.) I previously had it making a burst of five 15ns-long 250V 5A pulses, and everything was fine, perfect. But after fooling ar...


ltspice -- body effect and other matters

Started by Michael Robinson in sci.electronics.design10 years ago 11 replies

I need to be able to model a mosfet with values of L, W, Vth, Kprime, lamba and gamma, and I'm trying to figure out how to do this with...

I need to be able to model a mosfet with values of L, W, Vth, Kprime, lamba and gamma, and I'm trying to figure out how to do this with LTSpice. Looking at ltspice mosfet models, they don't have a separate value for K. They have Cgs, W and L. K is a function of Cgs, W, L, and electron mobility. So I could sort of kluge my own mosfet model by choosing Cgs so that K comes out just right. ...


A PIC based boost converter

Started by Jan Panteltje in sci.electronics.design9 years ago 2 replies

Updated the diagram for the 'on' and 'off' touch button MOSFET added. http://panteltje.com/pub/sc2_pwr_diagram_2_img_3235.jpg This MOSFET is...

Updated the diagram for the 'on' and 'off' touch button MOSFET added. http://panteltje.com/pub/sc2_pwr_diagram_2_img_3235.jpg This MOSFET is in a funny place, between the 2 batteries, this is to get enough drive once it is on. The BLACK button bridges the MOSFET, this starts the boost converter, then the PIC comparator senses if the battery is higher than 2.0V, if so it gives +5V to the M...


addendum to 45-year MOSFET history, comments?

Started by Winfield Hill in sci.electronics.design1 year ago 14 replies

I've written an addendum to the 18-page 45-year power MOSFET history article for the...

I've written an addendum to the 18-page 45-year power MOSFET history article for the x-Chapters. https://www.dropbox.com/s/0qh8dxgielrkqvq/chap-3x.11_MOSFET-saga_2019-07-19.pdf?dl=1 And would appreciate your comments. Here it is: As we leave this lengthy section, discussing various intricacies in the history of power MOSFETs, we have to admit not mentioning a few important MOSFET...


N-chl MOSFET Jellybean??

Started by RST Engineering in sci.electronics.design8 years ago 6 replies

Anybody got a suggestion for an N-channel MOSFET power device (prefer TO-220 or similar) that Joe Hamhand can get in East Undershirt Ohio on a...

Anybody got a suggestion for an N-channel MOSFET power device (prefer TO-220 or similar) that Joe Hamhand can get in East Undershirt Ohio on a Sunday afternoon? Thanks, Jim


Super low power isolated MOSFET driver

Started by Piotr Wyderski in sci.electronics.design7 months ago 25 replies

Hi, I need to slowly drive a high-voltage high-side MOSFET in a 5kV isolated setup. This use case reminds an electronic fuse: the MOSFET is...

Hi, I need to slowly drive a high-voltage high-side MOSFET in a 5kV isolated setup. This use case reminds an electronic fuse: the MOSFET is expected to be almost always ON, but the driver needs to start in an OFF condition. Generally the answer would be Si8261, but it requires ~50mW. So I have devised a much less energy hungry driver based on a tiny 1:1 bipolar drive pulse transformer ...


Measuring the Output Impedance of a (Large Capacity) Voltage Source

Started by Anand P. Paralkar in sci.electronics.design7 years ago 41 replies

Hi everyone, I am trying to test a MOSFET H-bridge at around 400V DC input. I need to observe the MOSFET Drain-Source waveforms for ringing...

Hi everyone, I am trying to test a MOSFET H-bridge at around 400V DC input. I need to observe the MOSFET Drain-Source waveforms for ringing during the on to off state (and vice versa) switching. I observe that the drain to source waveform is affected by the DC source that I use to supply in the input DC voltage to the MOSFET H-bridge. We have three different sources (including one ...


75332P MOSFET drain connected to which battery terminal?

Started by John Doe in sci.electronics.design9 years ago 18 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 ...


Dirt cheap inverter/buffer with RDSon < 10 ohm?

Started by Klaus Kragelund in sci.electronics.design3 years ago 19 replies

Hi I am using the 74AC14 for driving a medium power MOSFET I need it dirt cheap, so no external small signal MOSFET to help to drive the...

Hi I am using the 74AC14 for driving a medium power MOSFET I need it dirt cheap, so no external small signal MOSFET to help to drive the power MOSFET possible 74AC14, which is very cheap, has 24mA drive, ca. 0.65V, which translates to euquivalent RDSon to about 26 ohms http://www.mouser.com/ds/2/149/74ACT14-1006522.pdf I could parallel 2 of them, but since my input is slowly moving,...


Power MOSFET testing - NTE2382 N-channel

Started by Mike Miller in sci.electronics.design7 years ago 14 replies

All, I have been doing some testing using the NTE2382 N-channel MOSFET for a 24V...

All, I have been doing some testing using the NTE2382 N-channel MOSFET for a 24V application. http://www.nteinc.com/specs/2300to2399/pdf/nte2382.pdf 1.) Test 1 - MOSFET turned off. The 24V input is connected to the drain of the FET. The gate is tied to ground. 0V is measured on the source. Notes: This is what I expect to see when the FET is off - 0V on the output. 2.) Test ...


MOSFET hfe Beta current gain.

Started by Harry D in sci.electronics.design6 years ago 6 replies

Attached MOSFET device with a nice hfe of 95, who knew? http://www.genesicsemi.com/images/products_sic/sjt/GA50JT17-247.pdf Enjoy, Harry

Attached MOSFET device with a nice hfe of 95, who knew? http://www.genesicsemi.com/images/products_sic/sjt/GA50JT17-247.pdf Enjoy, Harry


Fail to amplify 27mhz rf using mosfet IRF843

Started by Anonymous in sci.electronics.design3 years ago 20 replies

I found old mosfet transistor IRF843, using 20k and 70k resistor, i manage to set the voltage at transistor gate to 3.9 volt and using 1uF to...

I found old mosfet transistor IRF843, using 20k and 70k resistor, i manage to set the voltage at transistor gate to 3.9 volt and using 1uF to channel the 27mhz rf signal to the transistor gate, i manage to get an audio from 8ohm speaker connected to the transistor drain. I'm using about 5.3 volt power supply from transformer. The audio is loud and clear. The mosfet gate can received


Faster than 2n7002

Started by Anonymous in sci.electronics.design5 years ago 29 replies

Cool part. 20V enhancement N-ch MOSFET. Vgs.th(100uA)

Cool part. 20V enhancement N-ch MOSFET. Vgs.th(100uA)


Astable multivibrator with MOSFET SPICE model

Started by Anonymous in sci.electronics.design5 years ago 16 replies

Could some electronics guru point me to a working(i.e., correctly simulates) astable multivibrator SPICE model with MOSFET only. I have two...

Could some electronics guru point me to a working(i.e., correctly simulates) astable multivibrator SPICE model with MOSFET only. I have two working BJT based astable multivibrator SPICE models. However, my MOSFET based astable multivibrator model, works as per hand calculation, but shows no oscillations with a regular SPICE .TRAN analysis. I have tried the standard SPICE tricks, as havi...