CC2640R2F: GPIO pulse current capabilities

Jonathan Drake

Part Number: CC2640R2F

Hello,

The datasheet states that most GPIO lines are capable of 4mA (2mA setting also available) and a few are rated at 8mA maximum. If the figures of the datasheet are used to calculate the effective internal resistance, values of around 60 Ohm would be expected for the 4mA setting. This implies short circuit current of 50mA from 3V VDD.

Having run some tests pulsing (several µs duration) a line loaded with various resistance values, I confirmed that the pulse currents are well in excess of the setting value. For example, with a 100 Ohm load the current was 13mA.

What level of pulse current can be safely taken from the GPIO lines?

Is there a Safe-Operating-Area (SOA) for the GPIO lines?

How does the current setting control the current (sensing the actual current, by thermal means, etc.)?

Kind regards,

Jonathan

over 4 years ago

0 Nathan Block over 4 years ago

TI__Mastermind 37780 points

Hi Jonathan,

Jonathan Drake said:
What level of pulse current can be safely taken from the GPIO lines?

The 8 mA number means we can only reliably confirm that these pins can draw 8 mA. You may be able to pull more current out of them by lowering the resistance, but we can't confirm the device will operate as expected if you choose to do so.

Jonathan Drake said:
Having run some tests pulsing (several µs duration) a line loaded with various resistance values, I confirmed that the pulse currents are well in excess of the setting value. For example, with a 100 Ohm load the current was 13mA.

If you're measuring 13 mA over a 100 Ohm load, then your device is outputting 1.3 V, which is below the 1.32 minimum figure, but not unexpected because you're taking the device above the maximum recommended current.