Article ID: 000077538 Content Type: Troubleshooting Last Reviewed: 09/11/2012

Can I drive LEDs without using current limiting resistors on the I/Os by adjusting drive strength to low?

Environment

BUILT IN - ARTICLE INTRO SECOND COMPONENT
Description

No, you have to put current limiting resistors. The drive strength given to the I/O of the device has an effect on edge rate, power and SSN. When you do not have a current limiting resistor, you are shorting the I/O of the device to GND through the LED.

Any short to ground will draw high current through the I/O and may damage the device.

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This article applies to 7 products

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