How to provide different voltages to the user, through a single channel (switching)?.

[Franco]

Hi folks:

I have a question.

From an I/O card I want to provide a variable output voltage to

energize
some little solenoids. In the board I have regulated 5, 12, and 24
volts, and
those are the voltages I want to deliver. I think I can deliver more
or less
300mA per channel (lets say: 5V-300mA, 12V-300mA, 24V-300mA). The last
are conservative values.

The important thing is: the output should be directed to the user
by using a single medium. So the user will have available 5, 12, XOR
24,
but not all at the same time. Nonetheless, those voltages are still
being used within the board, for some other tasks.

So, I am wondering, which technology to use for achieving that???

High side drivers and mosfets? (to switch between channels). (I dont
like
the space requirements)
Another smarter solution?

Drawing:

5 -------
|
12 ------- --------- output
|
24 -------


Best Regards...

Franco.

 

[[email protected]]

Hi folks:

I have a question.


energize
some little solenoids. In the board I have regulated 5, 12, and 24
volts, and
those are the voltages I want to deliver. I think I can deliver more
or less
300mA per channel (lets say: 5V-300mA, 12V-300mA, 24V-300mA). The last
are conservative values.

The important thing is: the output should be directed to the user
by using a single medium. So the user will have available 5, 12, XOR
24,
but not all at the same time. Nonetheless, those voltages are still
being used within the board, for some other tasks.

So, I am wondering, which technology to use for achieving that???

High side drivers and mosfets? (to switch between channels). (I dont
like
the space requirements)
Another smarter solution?

Drawing:

5 -------
|
12 ------- --------- output
|
24 -------

Best Regards...

Franco.

try lm317 or send me email with more details on my private
[email protected]
with subject lm317 not good for my application then I will connect you
with the other solutions

 

[Franco]

try lm317 or send me email with more details on my private
[email protected]
with subject lm317 not good for my application then I will connect you
with the other solutions

Hi, unfortunately I have to use the voltages I have available and not
to generate them again.
The chip is also too big for my design. Space is an important
constraint in this case.

Cheers...

Franco.

 

[John Fields]

Hi, unfortunately I have to use the voltages I have available and not
to generate them again.
The chip is also too big for my design. Space is an important
constraint in this case.

 

[Rich Grise]

Hi, unfortunately I have to use the voltages I have available and not
to generate them again.
The chip is also too big for my design. Space is an important
constraint in this case.

Three reed relays with a little bit of logic for the "one and only one"
function.

Good Luck!
Rich

 

[Franco]

---
If you have to supply power to ground-referred loads, then I'd go
with P channel enhanced mode MOSFETS or PNP transistors.

How are you planning on doing the switching?

Hi, the switching control will be done by a microcontroller on board.

I am looking for P channel enhanced mode mosfet. Do I need
a high side gate driver for driving them?

Cheers...

Franco.

 

[joseph2k]

Hi, unfortunately I have to use the voltages I have available and not
to generate them again.
The chip is also too big for my design. Space is an important
constraint in this case.

Cheers...

Franco.

Does it have to be able to change on the fly? (or do you have the luxury of
using a miniature rotary or slide switch or jumper or move a terminal to a
different position?)

 

[Franco]

Three reed relays with a little bit of logic for the "one and only one"
function.

Good Luck!
Rich

Hi man, thanks for the tip. I think reed relays suit my needs. Thanks
again.

Franco.

 

[Franco]

Does it have to be able to change on the fly? (or do you have the luxury of
using a miniature rotary or slide switch or jumper or move a terminal to a
different position?)

Hi Joseph, it must be able to change on the fly, but speed is not
important.

I have a microcontroller with some pins available to make the
switching.

Cheers...

Franco.

 

[joseph2k]

Hi Joseph, it must be able to change on the fly, but speed is not
important.

I have a microcontroller with some pins available to make the
switching.

Cheers...

Franco.

In that case i recommend two "TO-5" relays (actually in a TO-99 8 pin can,
like an old op-amp). Two of them should have a smaller footprint than
three reed relays. You probably will need transistors to drive the relays
either way.

 

[YD]

Hi folks:

I have a question.

energize
some little solenoids. In the board I have regulated 5, 12, and 24
volts, and
those are the voltages I want to deliver. I think I can deliver more
or less
300mA per channel (lets say: 5V-300mA, 12V-300mA, 24V-300mA). The last
are conservative values.

The important thing is: the output should be directed to the user
by using a single medium. So the user will have available 5, 12, XOR
24,
but not all at the same time. Nonetheless, those voltages are still
being used within the board, for some other tasks.

So, I am wondering, which technology to use for achieving that???

High side drivers and mosfets? (to switch between channels). (I dont
like
the space requirements)
Another smarter solution?

Drawing:

5 -------
|
12 ------- --------- output
|
24 -------


Best Regards...

Franco.

How do you distribute to the appropriate solenoid(s) on the receiving
side, or how will you know which solenoid is connected?

- YD.

 

[Franco]

Late at night, by candle light, Franco <[email protected]> penned
this immortal opus:










How do you distribute to the appropriate solenoid(s) on the receiving
side, or how will you know which solenoid is connected?

- YD.

In our system, the user is responsible for that connection.

Greetings...

Franco.