mosfet as switch

I have been reading this pdf from above

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what is confusing is on page 10 (4-10) THEY PUT 2 N-CHANNEL MOSFET back to back, with an arrow with current pointing to both direction, this seems wrong, I thought current can only flow in one direction, is this pdf right?

B
Reply to
lerameur
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I see only 6 pages in that data sheet, but the channel of a MOSFET can conduct current in either direction. The body diode in parallel with the channel can conduct only in one direction.

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Regards,

John Popelish
Reply to
John Popelish

I have been reading this pdf from above

formatting link
what is confusing is on page 10 (4-10) THEY PUT 2 N-CHANNEL MOSFET back to back, with an arrow with current pointing to both direction, this seems wrong, I thought current can only flow in one direction, is this pdf right?

B
Reply to
lerameur

Sorry , made a copy and paste mistake: this is the link:

formatting link

B
Reply to
lerameur

Sorry , made a copy and paste mistake: this is the link:

formatting link

B
Reply to
lerameur

link:

formatting link

I also made the schematic on page 10:

formatting link
I need to raise the voltage above 26v at the gate for it to conduct., as Vg needs to be higher. IS the tutorial off ?

B
Reply to
lerameur

link:

formatting link

I also made the schematic on page 10:

formatting link
I need to raise the voltage above 26v at the gate for it to conduct., as Vg needs to be higher. IS the tutorial off ?

B
Reply to
lerameur

Yes. In that configuration, the MOSFETs can conduct or block current in either direction.

--
Regards,

John Popelish
Reply to
John Popelish

In this schematic, you have not provided any way for the seriesed MOSFETs to see ant gate voltage but zero (or to be floating).

To see the switching you desire, put a pulsed voltage source from the common source node between the two MOSFETs to their common gate node.

Once you see them working (assuming the way it works is what you are looking for), we can figure out how to do this without a floating pulse source.

The schematic on page 10 of the PDF is not the actual circuit inside the package, but only a conceptual one. It shows what the outside world sees.

--
Regards,

John Popelish
Reply to
John Popelish

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That still makes no sense to me. 

If V2, V3, and V4 are to be used, how do you plan to connect their
grounds to the load?

If what you\'re trying to do is have a bunch of batteries that are
being charged in one bank and another bunch of batteries that are
being discharged in another bank, then you could do it like this, with
relays, and isolate the load completely from the charger: (View in a
non-proportional font.)


    +------+----------+-----------//--+
    |      |      +---|------+---//---|------+-----+
    |      |      |   |      |        |      |     |
    |      O->| | | | | |
Reply to
John Fields

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