IC for condensing multiple transistor based FET drivers

[ACharnley]

I have the attached circuit, two NPN's and a PNP duplicated 10 times in a circuit. Although they're SOT-363/SC-88 I'm wondering if there's a smaller IC which either does the same or has many BJT's in it.

(I've looked at darlington arrays, they all appear to be dual NPN based).

6 of these drivers are low current (< 10mA) and really are for voltage translation. I've looked at using buffers like the ULN series but they're open collector so more wasteful on power.

Perhaps I'm missing knowledge of a chip, please enlighten me!

 

[ronsimpson]

1-gate driver
FAN
Micro Chip
Low current translator
PNP & NPN
two h-bridge npn&npn Look at this one.
I did not get enough information but here are some different types.

 

[rjenkinsgb]

Perhaps I'm missing knowledge of a chip, please enlighten me!

What are the input and output / supply voltages?

Are the inputs from discrete circuits or a microcontroller?

 

[ACharnley]

Ron I looked at all those, only the cd4504b would save space but it's current output is tiny.

Most of these are fairly expensive as well, I don't know why given they do so little.

Input is CMOS/Pic, max switching voltage is 10-12V.

 

[ronsimpson]

6 of these drivers are low current (< 10mA)

I looked at "level translators" for this. Many can output 12V.

I don't know why given they do so little.

Most "Gate Drivers" can do 2A to 10A depending on what type. They are not built to do high current all the time. They are built to do 10A for the time it takes to charge up the Gate. Part of the complicity is the input range is for 3.3V or 5V or 2.5V logic while the out levels are for 12V or 18V some to 25V. The inputs are often Schmitt trigger for noise reduction. The outputs can handle some inductive kick back from the Gate and long traces.
It is hard to find more than 2 drivers in one IC.
Some of the Bridge Gate Drivers may have timing circuits to force dead time.
They use a large piece of silicon because the two output transistors (MOSFETs) are high current parts.
Often there is a voltage regulator to power the input pins.

 

[ACharnley]

I'm only driving small FETs, it's 10V-12V to overcome the 3.3-5V at the NMOS high side.

Anyhow, I couldn't find anything suitable do it's back to DIY (which also has the benefit of being cheap - 7 drivers and 4 FET multiplexing drivers cost $0.50).

I may have to revisit it for floorspace but for now I'm only prototyping.

Thanks for the assistance.

 

[ronsimpson]

 

[ACharnley]

Any benefit over the typical NPN/PNP + NPN? I suppose it's slightly smaller.

 

[rjenkinsgb]

The nearest I can find is a CD40109 - That's a four channel 5V to (up to 18V) translator, but it's only rated 6.8mA out..

https://www.ti.com/lit/ds/symlink/cd40109b.pdf

£0.43 at one off from farnells:

https://uk.farnell.com/texas-instruments/cd40109be/ic-level-shifter-quad-16dip/dp/3120902

 

[ACharnley]

It's ok, I've committed to the DIY drivers for the prototype at least.

Somewhat related, the MMBT3946 is 200mA rated and the MMDT2227 is 600mA rated, however the 3946 has a max wattage of 150mW and the 2227 is 200mW. What defines the continuous current? These figures suggest it's not heat, that the 2227 has a lower voltage drop?