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TLC5944: Optimizing power consumption (VCC), with all LED's off

Part Number: TLC5944

Hi, I'd like some input on how to read the supply current specs for the TLC5944 led driver.

  • Can I assume that Icc3/Icc4 in the datasheet (picture below) is without any LED's "on"?
  • Why does Typ/Max increase together with Riref?
    • it seems to have a relation with the constant current setting
    • please clarify what can be done to reduce the current consumption unrelated to actual sink led-current.

 replied (in now locked thread):

Icc3/Icc4 is with LEDs all on of full greyscale while Icc1/Icc2 is without any LED's ON since BLANK is high.

Rief changes the Reference Current in IC and will cause Typ/Max's cahnge. You can refer to the function block diagram.

Follow-up questions:

- Icc3/Icc4, please clarify why the numbers are different as only the Riref resistor has changed (the numbers in the table I assume excludes the actual LED's)

- If we lower DCn (dot correction current register) to say half of the configured Riref, will this also lower the current consumption of the led-driver itself?

- As Icc1/Icc2 will show an increase in quiescent current when led's are off (blank is high), is there a way to reduce the quiescent purely in software? (i.e. I don't want to switch the supply off, nor trying to actively increase the resistance of Riref)