Are there options to reduce Lepton`s FFC power consumption?

The nominal resistance of Lepton`s shutter coil is 12 ohm at 20C; if VDDIO is set to its minimum value, 2.8V, then the nominal power dissipation is 653 mW. The shutter is actuated for approximately 800 msec per FFC event, which means 523 mJ nominal. However, if VDDIO is set to its maximum value, 3.1V, then power dissipation is 800 mW, and energy consumption is 640 mJ. At higher temperature, the coil resistance increases (power decreases); the opposite is true at cold. Here is detail of coil resistance variation due to tolerance and temperature:

 

min

nominal

max

-10 

9.3

10.4

11.5

  25

10.8

12.0

13.2

  65

12.5

13.9

15.4

Operating VDDIO at 2.8V instead of 3.1V is the best opportunity for reducing power/energy. FLIR is exploring the possibility to slightly reduce the actuation time of the Lepton shutter during FFC, but at the most, it will decrease actuation time by 100 to 200 msec. That is the next best opportunity for reducing energy consumption.

Back