Can some explain this High side powe switch

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It is mentioned that this power switch is N channel . According to my knowledge Source should be negative voltage,
Gate should have a positive voltage to make the drain active,

But the diagram shows n channel mosfet but source is positive a gate is nagative,

Can someone explain this,

2

The charge pump generates a gate voltage that is higher than the source voltage so that MOSFET can turn on

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3

If gate voltage is higher than source voltage, can we turn on n channel mosfet with negative?

4

What do you mean negative?
If the gate voltage is higher than then source voltage (positive) the MOSFET is on if it is less (negative) it is off.

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The question is N channel mosfet turn on when positive voltage is given to gate , and source should be negative,

P channel is opposite of that,

Is that correct?

6

No

N channel turns on when gate is positive relaative to sourse.
For example if source is at 12V and gate is at 18V then MOSFET is ON.
Or, source can be 0V and gate 6V and MOSFET will be ON.

7

The in p channel?

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As you said n channel turn on with positive voltage in gate,
Why does the above diagram shows the n channel mosfets gate should be a negative IN put?

Thats my problem,,

9

Just the opposite.
The gate must be negative relative to the source to turn it on.
If source is 12V and gate is 6V then gate is -6V (6V-12V = -6V) and MOSFET is ON.

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10

That is not a MOSFET, it is a high side switch.
To turn it on you need to connect the input pin to ground.

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11

Thanks sir, I understood,
I saw the n channel mosfet symbol, in the diagram
Thats why I asked why negative volatage for gate

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12

The diagram is complicated and does not show details. It just there to give you an idea of the functions done inside the IC. The important information is given in the tables.

What do you plan on doing with that switch?

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13

Its in a gear box control unit,
On a prime mover,
Gear shifting solanides are controled by those switchs

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This footnote is probably the most important piece of information regarding, turning it on/off

We recommend the resistance between IN and GND to be less than 0.5kΩ for turn-on and more than 500kΩ for turn-off.
Consider that when the device is switched off (IIN = 0) the voltage between IN and GND reaches almost Vbb

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