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Total sink or Source

10gigbill10gigbill Posts: 79
edited 2010-01-19 04:28 in General Discussion
The spec sheet sez 3o ma per I/O pin. can I source or sink a total of 600 ma?

or is the max current limit on the Vdd ?

Thanks.

Comments

  • Mike GreenMike Green Posts: 23,101
    edited 2010-01-18 16:57
    The datasheet says 130mA maximum for Vdd and Vss and 45mA maximum for any I/O pin (SX20/SX28).

    The SX48 datasheet has different values. It's 180mA for Vdd and Vss (at 70C), 45mA for any I/O pin and 50mA for each group of I/O pins (read the datasheet for details). The overall current is higher when the chip is kept cooler, again read the datasheet for details.

    Post Edited (Mike Green) : 1/18/2010 5:05:53 PM GMT
  • 10gigbill10gigbill Posts: 79
    edited 2010-01-18 18:39
    Thanks Mike:
    Just wanted to make sure. So if I want to drive one LED off of each I/O pin I will buffer the I/O with a few ULN2803's.

    Bill
  • PropabilityPropability Posts: 142
    edited 2010-01-19 04:28
    ·Bill

    ·If you just want to hang leds on the pins then just don't turn them all on at the same time(just like segment displays that turn on in a timed sequence). This does take some processor time but it would aleviate the need for the 2803's. Just thinking in the sense of budget and what the SX can do.
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