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Resister used in Open Drain output port. Necessary?

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wzhe6095

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In the cell charge management controller, such as MCP73861(or MAX1926), the Status Output Pin is

Open Drain Output, and it can sink current of 7mA. If I attach a LED to this pin, whether a resistor is

needed between the LED and the Power? If it isn't needed, the ON resistor of the MOSFET may be small,

will the OUTPUT Moudle be burned?

Thank you for answering~
The picture is part of the typical application circuit of MCP73861. We can get there is no resistor connected to te LED.
 

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Audioguru

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The datasheet says, "direct LED drive" because the output current is already limited. Therefore no resistor is needed.
 

Borber

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wzhe6095

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Thank u for answering my question, It's very helpful~

- - - Updated - - -

Thank u for answering, I misunderstood this sentence.
The datasheet says, "direct LED drive" because the output current is already limited. Therefore no resistor is needed.
 

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