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I use a lot of 2N3906 pnp bipolar transistors and 2N7002 n channel mosfets on my pcb. I was suprised to see that there are no cheap and commonly available IC packages for these common transistors as arrays. I have a special configuration so that the microcontroller's output switch to a negative rail. Because of that reason i can not change the type of the transistors to npn type where common and cheap packages exists (ex. uln2003)

Example : switching to negative rail through microcontrollers output

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  • \$\begingroup\$ Availability of components often correlates with the abundance of possible applications. \$\endgroup\$
    – PlasmaHH
    Jun 1, 2017 at 8:16
  • \$\begingroup\$ There are loads of MOSFET arrays - I've been looking them up in the last week and there's piles. Go to a distributor's website and search for them. Distributor I looked on has a category for them, separate to FETs. Maybe that's where you're going wrong, only looking in the FETs category. Anyway, there they are. \$\endgroup\$
    – TonyM
    Jun 1, 2017 at 8:18
  • \$\begingroup\$ I searched mouser and farnell, there are some quads with exotic prices. (ex: x30 price of uln2003). I appreciate any link to mosfet and pnp bjt arrays 8 channel . thanks \$\endgroup\$
    – rxpu
    Jun 1, 2017 at 8:22
  • \$\begingroup\$ Not very well, I'm afraid :-) Digikey have loads. \$\endgroup\$
    – TonyM
    Jun 1, 2017 at 8:54
  • \$\begingroup\$ I also checked the digikey. Yes. My problem evolves from technical to trade related. I have 1600 pcb having 36 pairs of pnp bjt and mosfet. (total 57600 2N3906 and 57600 2N7002). Suprisingly the cost of single package is 1600usd where the cost of array Ics is more than 24600usd. I must improve my relations with the loan pick and placer \$\endgroup\$
    – rxpu
    Jun 1, 2017 at 9:08

2 Answers 2

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Of course they exist. Here are PNP transistor arrays: http://www2.mouser.com/Semiconductors/Discrete-Semiconductors/Transistors/Bipolar-Transistors-BJT/_/N-ax1sh?P=1z0y4cnZ1z0y25uZ1z0rupj
I'm sure you can now find N-channel MOSFET arrays too.

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  • \$\begingroup\$ I think i must exercise and sharpen my skills searching mouser catalog. Thanks. albeit, 2N3906 costs 10 cents, the quad 2N3906 in a package costs 80 cents, Very strange. It is 2 times more expensive. I expected it to be cheaper because of 1 packega cost against seperate 8 packages. Anyhow thanks for your help \$\endgroup\$
    – rxpu
    Jun 1, 2017 at 8:37
  • \$\begingroup\$ @rxpu There are billions of NPN BJTs used and relatively few arrays. If you get transistors by the reel they can be quite inexpensive. \$\endgroup\$ Jun 1, 2017 at 16:56
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You can get a 7 channel MOSFET from TI: -

enter image description here

It's called a TLP7407. There is also this 8 channel MOSFET output device from TI: -

enter image description here

The ULN2003LV is also a MOSFET output and has 8 channels: -

enter image description here

Mitsubishi also supply an 8 channel device that has the same functionality as a PNP in that it's ouput pulls up to the positive rail. However, it is inverting compared to a conventional PNP. It's called a M63840P.

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  • \$\begingroup\$ Thank you for your help, ULN2003Lv would be just right (price and availability) but unfortunatelly the gate resistor is not suitable for my application. Other items are hard to find , but i will investigate further. \$\endgroup\$
    – rxpu
    Jun 1, 2017 at 9:00
  • \$\begingroup\$ You can always put a resistor in parallel. \$\endgroup\$
    – Andy aka
    Jun 1, 2017 at 9:03
  • \$\begingroup\$ Yes the 300kohm resistor is easy to bypass, but the gate resistor (3kohm) can not be bypassed (i would need a gate resistor of 10 ohm) \$\endgroup\$
    – rxpu
    Jun 1, 2017 at 9:12
  • \$\begingroup\$ Dear andy , I adjusted the gate resistor to 3kohm sacrificing some speed and i think i may use uln2003lv as n-channel mosfet array (it is cheap). Thank you again for the useful tip. \$\endgroup\$
    – rxpu
    Jun 1, 2017 at 10:43
  • \$\begingroup\$ OK good luck and give these answers a couple of days to see if there are any better answers before formally accepting. \$\endgroup\$
    – Andy aka
    Jun 1, 2017 at 10:47

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