I am using Vcc 12v and have a CD4022 giving 8 bits output. Each of the outputs needs to be connected to a DYHV20T PLAYER module. This module gives out 3.3v. These signals each need grounding but only 1 at a time.

I plan on using mosfets driven by the 12v signals given out by the CD4022. I have plenty of IRLZ44's N type (that I do not mind blowing up), but I am unsure of a recognised schematic. Need to be in open-drain MOSFET configuration, whatever that means??

Do I need 12v onto drain or would the 3.3v suffice, and being pulled to earth?

 

You don't need a drain connection to 12V.
Just connect the drain directly to the 3.3V signal.
The MOSFET then acts as a switch to ground.

 

I had got that down as a possible circuit, but could not find any confirmation on Google.

Thanks for quick response.

 

Google “open collector switch”

 

Just use an inverter after each output. You don’t need discrete MOSFETS.

 

Make your life easier and use these.
TBD62084APG Toshiba Semiconductor and Storage | Integrated Circuits (ICs) | DigiKey
TBD62083A series, TBD62084A series

 

Use a 74LVC07 (or 74LVC05 if you want it inverting)

 

I am using Vcc 12v

Just use an inverter after each output. You don’t need discrete MOSFETS.

Use a 74LVC07 (or 74LVC05 if you want it inverting)

Neither recommended for a Vcc of 12V for the gates.

The CD4022 could possibly be used with Schottky diode isolators on the output.
The should pull the output below 0.5V when low which likely is sufficient for a DYHV20T input low logic level.

 

? 4/3x https://www.nexperia.com/product/HEF7069UBT (ancient // open drain 4069)
? 4x https://www.analog.com/en/products/lt1015.html (may be avail // would be an overkill compared to CD4000 series speed)
it seems TLV1872 is a bit slower analog of the LT1015
(there might be more suitable open collector or open drain comparators LM339 is likely faster than tlv1704)
? 4x https://www.infineon.com/part/2N7002DW (there might be more suitable mosfet matrix ic-s)

update : it looks the mosfets are bloody slow

 

Interesting stuff.

How could I use CD4030 or CD4070 – Quad 2-input open-collector XOR gates.

My Vcc is 12v

I assume the insides of these CD chips are similar to



So again, I assume to ground my 3.3v signal, all I would need to is to apply it to the collector of the output transistor. Not sure if a resistor would be needed.

The logic does not quite work out, as I need only 1 input to be high for the output pin to be 0. This would mean the other input pin is to be tied to 0volts GND

 

Forget the logic chips and just use a load driver as I posted.

You get 8 MOSFETS in a single chip.
They have their inputs (gates) directly across from their outputs (drains).
But I mean, if simplicity, convenience and ease are not your thing...then go ahead and knock yourself out.

 

How could I use CD4030 or CD4070 – Quad 2-input open-collector XOR gates.

My Vcc is 12v

I assume the insides of these CD chips are similar to

No.
Those chips are essentially identical and neither is open-collector output.
They have the normal push-pull complementary transistor output stage.

 

You get 8 MOSFETS in a single chip.

Hi ya, are you referring to TBD62083A. It says these only have 8 x Darlington transistor array and no mosfets, the datasheet refers to 8 open-collector outputs (can sink current). But in looking at the typical circuits, it shows them as being mosfets??

I suppose as long as they do the job.

They are looking good as they can run at 12v Vcc.

They could do the job, thanks for the info.

Also looking at CD4066 analogue switch, but I think that's out the window, as too much 'contact' resistance.

 

how about your actual timing requirements - a simple resistive divider might be an option if the timing is not too critical
+ it likely also involves the available system/PCB space and power consumption we need to be considering ??
↑ the most viable solution is dependent on above ↑

 

Hi ya, are you referring to TBD62083A. It says these only have 8 x Darlington transistor array and no mosfets, the datasheet refers to 8 open-collector outputs (can sink current). But in looking at the typical circuits, it shows them as being mosfets??

I have no idea where you would be getting such information, these chips use DMOS.

 

does not need to be a mosfet, any transistor or IC with open collector or open drain will do. speed does not matter either since this is a replacement for manually activated buttons so any semiconductor will be faster.any 74xx07 will do, or ULN2003, ULN2083, tpic2701...

 

I am using Vcc 12v and have a CD4022 giving 8 bits output. Each of the outputs needs to be connected to a DYHV20T PLAYER module. This module gives out 3.3v. These signals each need grounding but only 1 at a time.

Is this a continuation from this thread?
https://forum.allaboutcircuits.com/...v into one that requires a +voltage ??,-Reply

 

sounds like a useful reference on your gizmo
https://forum.arduino.cc/t/xy-v17b-mp3-sd-card-reader-warning/550832

? 3.3V TTL input ?
a note -- the 5V TTL SN7400 input is at threshold when you shunt it to the GND with 1.8kΩ to 2.4kΩ resistor meaning @ 1.28V INP
to force its OUTP to valid logic HIGH took some (i don't remember) . . . say 10% of 5V = 0.5V → fuzzy estimate 581Ω to 775Ω !BUT! it's for the 7400 series
(speculating) . . . meaning -- if you pull about 1mA from your input it should activate it ???

the 2n3904 ver. above can be fit for 2N2222 matrix https://www.tti.com/content/dam/ttiinc/manufacturers/tt-electronics/PDF/MCABT8E2222C6.pdf or SMD-s
https://assets.nexperia.com/documents/data-sheet/MMBT3904.pdf

 

Is this a continuation from this thread?
https://forum.allaboutcircuits.com/threads/how-to-make-a-pushbutton-that-earths-a-signal-to-0v-into-one-that-requires-a-voltage.207680/page-2#:~:text=General Electronics Chat-,How to make a pushbutton that earths a signal to 0v into one that requires a +voltage ??,-Reply

Yes you are correct, but things have changed dramatically. But thanks for adding the back link.