MOSFET Arrays? A beast that doesnt exist?

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#1
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Hi guys, I have googled high and low for a MOSFET array. Something like our good old transistor array ULN2803 but with FETS instead of transistors.

I am switching a 3.3V power supply and cant afford the volt drop of a transistor array.

I need 16 x N-channel and 16 x P-channel MOSFETs. At the moment I am just plonking down an individual SOT-23 FET for each one (800mA, 20V).

But I really feel like am making it overly complicated in terms of wiring up this PCB.

It seems like a common FET Array doesnt exist? Something like like 8 FETS?

All that I can find is a Mini 8 pin IC package with with one P and one N channel FET.

I am sure if the manufacturers start producing something like this it would be a hit. What do you think?

Just a noob in this crazy world trying to get some electrons to obey me.

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TPIC6B595? Or maybe one of its variants.

http://focus.ti.com/lit/ds/symli...

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Dual N channel MOSFETs in a SOT23-6 are available; like the FDC6401N.

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Quad N channel any good? Try Googling VQ1000.
There is also a quad P channel but i cant remember the part number.

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Kartman wrote:
TPIC6B595? Or maybe one of its variants.

http://focus.ti.com/lit/ds/symli...

What a beauty of a chip!!! 8 mosfets and its got the shift register packaged inside it! Hard to beat that.

If the output pins were all on one side, and the Ron was a bit lower I think i would be in love. Thanks Kartman!!, I wish I knew how you know everything about anything.

But I can get this one which has only 1.3Ohm on resistance!!
TPIC6595, And i can get it locally woohooo!! :) :)

Thanks Kartman!!!

Just a noob in this crazy world trying to get some electrons to obey me.

Last Edited: Mon. Jan 18, 2010 - 09:49 PM
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But you P and N, how are you going to solve that with this IC?

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jayjay1974 wrote:
Dual N channel MOSFETs in a SOT23-6 are available; like the FDC6401N.

Neat little compact thing. And I like the pin out configuration, it would be easy for me to arrange them densely. I am saving that one in the my tool box thank you!

To Solve the problem of the P-Channel, I would like to find some dual P-Channels equivalent of these chips.

Just a noob in this crazy world trying to get some electrons to obey me.

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dylan85 wrote:
Quad N channel any good? Try Googling VQ1000.
There is also a quad P channel but i cant remember the part number.

Those are pretty cool, unfortunately the pin lay out would be difficult for me to pack them densely in my application.

Just a noob in this crazy world trying to get some electrons to obey me.

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jayjay1974 wrote:
But you P and N, how are you going to solve that with this IC?

I am not sure. I was thinking of driving the gate of some of the N-channels really high so that they could source current, but I see the max Vcc (what is applied to the output MOSFET) of the shift registers is 5.5V. So its not too flexible there. Well at least half of the array has dissappeared!

Just a noob in this crazy world trying to get some electrons to obey me.

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http://www.irf.com/product-info/...
A n & p in 9 mm^2 (a Micro6).

"Dare to be naïve." - Buckminster Fuller

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Hi,

 

I'm rescucitating this thread because I've been looking for the same unicorn as the op, and this forum ends up in the very first google results.

Toshiba has the TBD62xxx series that has 8 NMOS in a package that is pin-tp-pin compatible with the ULN2803.

 

Best regards

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Hi idobox, I think the Toshiba TBD62783 is a P-channel  MOSFET array with a built in driver  for each MOSFET. Am I right?

farmerkeith

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Diodes.com DMN1250UFEL is a 4 N-channel device

 

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Well, I'll contribute with some MOSFET arrays I know, in case someone needs them:

 

The 4007, from the 4000 logic series.

The SN74TVC3306 and the LSF0204,from TI. The later is a member of a family of devices, so there are more.

 

Edit: just remembered there is a smaller company that has specialized precision MOSFET arrays: http://www.aldinc.com/ald_mosfetarrays.php

Last Edited: Sat. Mar 4, 2017 - 12:17 PM
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Just because I don't want anyone being misled by this, no, the Toshiba TBD62783 and co. is an n-channel DMOS array with a clamping diode on each driver (for use with inductive loads).

 

You were probably confused by the fact that in the schematic in the TBD62783 datasheet, gnd is at the top and the n-chan mosfets are drawn upside down as compared to their normal portrayal. But they're still draining conventional current, not sourcing it.

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In case anyone needs an H-Bridge: DMHC3025LSD
Edit: I mixed something up. I claimed it's an expensive part, but it isn't at all

"Some people die at 25 and aren't buried until 75." -Benjamin Franklin

 

What is life's greatest illusion?"  "Innocence, my brother." -Skyrim

 

Last Edited: Sun. Jan 14, 2018 - 09:09 PM
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Uhmm...

Just to make sure no one is misled when searching for info on using Toshiba's relatively new (2016) improved chip TBD62783.

 

I'd just looked at a shield design using this chip. And came across this post in my searching.

Note the "7" in the part number is a seven, not a zero.

Hence it is does NOT have N-Ch outputs.

They are P-Ch MOSFETs.

So it is meant to source (positive) current out its pins.

The catch diode is to ground, which is appropriate for sourcing current to a (mildly) inductive load.

 

I'd reference you to review the equivalent circuit diagram in the chip's datasheet (it was on page 2 in a recent pdf version). It is quite clear.

While there is an N-Ch MOSFET in the input stage, that is not the output stage.

 

Interesting chip. Cheap, and up to 500mA!

But gotta watch the heat though - none of those packages are really thermally enhanced! Nor do they make it easy to figure out how much current it can handle steady state... (there are standard diagrams for duty cycle limits - not sure why they didn't use a little more ink to document safe ranges for different packages)

Cheers.

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Watch out for the total package dissipation on those things with more than 1 transistor in them. Same thermal rules as singles but it is easy to think "each is rated for 1A, so 2A is OK for the package".

 

Jim

Jim Wagner Oregon Research Electronics, Consulting Div. Tangent, OR, USA http://www.orelectronics.net

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Bleh, these are some shabby fets:  1.6 ohm, 3.25 ohms max....seems to be at the upper end of sad..

I suppose, ok, if you barely need any current or can tolerate vdrop.

 

Take a look at the NCV7708...been pretty happy with it....though I wish it had better fets (0.8 ohm typ) too.

https://www.mouser.com/Search/Refine.aspx?Keyword=NCV7708

 

 

 

 

 

When in the dark remember-the future looks brighter than ever.   I look forward to being able to predict the future!