Or bend upwards every other pin and solder the remaining to a normal 0.1" protoboard.

 

Si makes a lot of those low power MOSFETs, mostly surface mount.

You may also look into bs107/170/270/... And vn2222 - pretty much 2ñ700x in a different name.

One amazing MOSFET for analog use is irf510.

 

I've read in a couple of places people being disparaging about 2N7000s, but then the suggested alternative is along the lines of AO3418 which is nothing like it: The gate charge is at least 100x greater and it's not available in a TO-92 package.

Does anyone know of a more modern version of 2N7000 but with improved Id for lower Vgs with pC gate charge (not nC)? I'm working on a Li-ion charger that drives FETs from 5V logic and I'm hoping to drive up to 1A pulsed (500mA would do) with Rds <1ohm. I'd also like to avoid spending £1 per device, although obviously I don't expect all of this quite as cheap as the 2N7000. I've tried the digikey tool to no avail.

Perhaps I'm asking for too much and 2N7000 has been criticised unfairly?

2N7000 Vgs of 3 V or less. What do you need?

 

2N7000 Vgs of 3 V or less. What do you need?

Something so modern that it is not in a TO-92 package but in a TO-92 package.

 

Something so modern that it is not in a TO-92 package but in a TO-92 package.

You could use a 2x2 header like this, pull the fourth pin out and solder a SOT-23 in the middle
http://img.directindustry.com/images_di/photo-g/20825-2955917.jpg

 

I've read in a couple of places people being disparaging about 2N7000s, but then the suggested alternative is along the lines of AO3418 which is nothing like it: The gate charge is at least 100x greater and it's not available in a TO-92 package.

Does anyone know of a more modern version of 2N7000 but with improved Id for lower Vgs with pC gate charge (not nC)? I'm working on a Li-ion charger that drives FETs from 5V logic and I'm hoping to drive up to 1A pulsed (500mA would do) with Rds <1ohm. I'd also like to avoid spending £1 per device, although obviously I don't expect all of this quite as cheap as the 2N7000. I've tried the digikey tool to no avail.

Perhaps I'm asking for too much and 2N7000 has been criticised unfairly?

AFAICR: the BS170 has slightly better spec than the 2N7000.

Its available in TO92 or SMD - I think the SMD version of the 7000 is 7002.

Can't remember the TOxxx designation, but there's a line of "baby" TO220 MOSFETs that will pretty much fit the same space as a TO92. They were probably originally designed to supersede TO126 form. They are also SMD or through hole. The SMD parts sometimes turn up on PC motherboards, Id is usually in the general direction of 50A. The ones on MOBOs can be as low as 20V and with correspondingly low VGSthr - they're as good as logic level, and sometimes better.

 

You can take a surface mount part and super glue it upside down on your perf board. Just remember to mark pin one.

If you want to prototype smd devices on a perf board or bread board and re-use them, I've found that a a very small piece of blue tac will hold them in place and makes for easier removal than super glue

 

http://www.digikey.com/product-sear...t=0&page=1&quantity=0&ptm=0&fid=0&pageSize=25

11 pages of TO-92 FETs

 

http://www.digikey.com/product-search/en/discrete-semiconductor-products/fets-single/1376381?k=&pv16=12781&pv16=13139&pv16=13257&pv16=6381&pv16=12426&FV=fff40015,fff8007d,1140050&mnonly=0&newproducts=0&ColumnSort=0&page=1&quantity=0&ptm=0&fid=0&pageSize=25

11 pages of TO-92 FETs

But only a handful left after you click,
"in stock",
"logic level" (or less),
200 mA or more,
Input capacitance of 50pF or less
quantity of 1,

Ultimately only 2. I didn't check other parameters but to one remaining looked pretty good. 2N7000
The other was
http://ww1.microchip.com/downloads/en/DeviceDoc/TN2106 B080913.pdf

 

ZVN4206AVSTZ
60 Volt VDS *
RDS(on)= 1Ω *
Case E-Line TO92 Compatible
Repetitive avalanche rating *
No transient protection required *
Characterised for 5V logic driver
APPLICATIONS * Automotive relay drivers * Stepper motor driver
Continuous Drain Current 600mA
On-State Drain Current 3A
Pulsed Drain Current 8A
Input Capacitance <100pF
http://www.diodes.com/_files/datasheets/ZVN4206AV.pdf

 

Well done Bordodynov. I think that's the closest to a straight answer I've got. And yes you've ticked all the boxes including price at ~25p a unit. ZVN4206 dropped off my filter because the Rds is borderline at ~1V drop for Id=1A and Vgs=5V.

However after accepting that I may need to compromise on package I am staggered at the FDV303N. The chart of Id vs Vds for various Vgs is a thing of beauty. Less than 0.5V drop for 1A with Vgs=4.5V. The abs max ratings aren't as impressive but they're good enough for me and it comes with a zener diode to protect the input which will save me an external component.

 

Well done Bordodynov. I think that's the closest to a straight answer I've got. And yes you've ticked all the boxes including price at ~25p a unit. ZVN4206 dropped off my filter because the Rds is borderline at ~1V drop for Id=1A and Vgs=5V.

However after accepting that I may need to compromise on package I am staggered at the FDV303N. The chart of Id vs Vds for various Vgs is a thing of beauty. Less than 0.5V drop for 1A with Vgs=4.5V. The abs max ratings aren't as impressive but they're good enough for me and it comes with a zener diode to protect the input which will save me an external component.

The 100pF input capacitance is way higher than the 2N7000 making this new proposal slower (not better) than the ancient standard.

 

I see it also come in an array, albeit a 2/per SMT package .
(BTW does Betty still know they are harassing you)?
Max.

 

Yes, but I was quite vague about the input cap requirements (because I don't *need* it quite as low as the 2N7000). Anyway, FDV303N is far better for me now that package has been compromised.

 

If you want a good switch, look at IRLML0060 for example, 116 mohm with 4.5V at the gate.

 

Nice also, although gate cap is almost nF territory. With an abundance of choice of these modern devices it doesn't seem practical for ebayers to stock packs of 10 of everything. Tonnes of people are selling 10x2N7000 for £1 inc delivery. Does everyone just accept if you want a modern component you go to RS and pay RRP? Unfortunately there isn't a filter on digikey "available on ebay in handy packs"

 

Well done Bordodynov. I think that's the closest to a straight answer I've got. And yes you've ticked all the boxes including price at ~25p a unit. ZVN4206 dropped off my filter because the Rds is borderline at ~1V drop for Id=1A and Vgs=5V.

However after accepting that I may need to compromise on package I am staggered at the FDV303N. The chart of Id vs Vds for various Vgs is a thing of beauty. Less than 0.5V drop for 1A with Vgs=4.5V. The abs max ratings aren't as impressive but they're good enough for me and it comes with a zener diode to protect the input which will save me an external component.

So the suggestion that a BS170 has slightly better spec wasn't a straight answer?!!!.

Maybe the other possible options confused you a bit.............

 

The BS170 doesn't really get close to passing the criteria I listed. Driven with 5V Vgs it can't pass 500mA, and even to pass 400mA it has a 1.5V drop so Rds is more like 3-4ohm.

But you're right. There were a lot of suggestions and I couldn't give a critique of every one. Thank you for yours