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I am using the MSP430F5438A-EP microcontroller. I wanted to know the max current that could be sourced by this chip. The datasheet is -Datasheet.

The data given in page 38 states - Diode current at any given pin = 2mAmps. The diode, I believe, is the protection snubber circuit in each GPIO. Right ? Hence, I am safe in assuming that each pin can source a max of 2mAmps ?

Absolute rating.

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No. That's how much current will destroy the voltage protection diodes if a voltage above or below the maximum values is applied to a pin.

The maximum current available is described on page 44, in and just below the "Outputs – General Purpose I/O" tables.

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  • \$\begingroup\$ But this gives the total current supplied by the chip. Not the individual pin max current sourcing. I am looking at the max current that can be sourced. \$\endgroup\$
    – Board-Man
    Sep 22, 2015 at 9:13
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    \$\begingroup\$ @VinodKaruvat the protection diodes are when the IO is an input. Sourcing current is different to diode clamp current. \$\endgroup\$
    – Andy aka
    Sep 22, 2015 at 9:18
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    \$\begingroup\$ @VinodKaruvat: How much current you can source depends on what voltage drop you can tolerate. See the tables for details. \$\endgroup\$ Sep 22, 2015 at 9:23
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    \$\begingroup\$ @VinodKaruvat the max current of 100mA is for the sum total of GPIO pins used to source (or sink) current. Each pin can say source 10mA but no more than (say) 10 pins can be used for doing this. \$\endgroup\$
    – Andy aka
    Sep 22, 2015 at 9:32
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    \$\begingroup\$ electronics.stackexchange.com/questions/103894/… \$\endgroup\$ Sep 22, 2015 at 9:36
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There is no single number. The current depends on supply voltage, high level output voltage VOH, temperature. Fortunately, the datasheet provides curves like this: enter image description here (pp.45-46 in the datasheet)

Related

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Discussion about digital output current in PICs.

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