110118-0001A
59
6.3.5
Power Consumption
The following table lists typical power consumption for the BitsyXb with varying input voltage
and activity levels. Run mode efficiency of the power supply decreases slightly with higher input
voltages.
Power consumption varies based on peripheral connections, components populated on the system
and the LCD panel connected. Input voltage, temperature and the level of processor activity affect
power consumption to a lesser extent. The measurements are accurate to
±
5-10%.
LCD displays and backlights add significantly to the total power consumption of a system.
Eurotech Development Systems include the Sharp LQ64D343 5V TFT VGA display, which draws
about one watt, and the Taiyo-Yuden LS520 backlight inverter, which draws about six watts at full
intensity.
Test Condition
VBATT_POS
6.5 V
9 V
12 V
15 V
Sleep mode
5
33
4
36
3
36
3
45
CPU idle (note 19)
85
550
66
590
52
620
44
660
Run mode, max (note 20)
260
1690
190
1710
175
2100
140
2100
Units
mA
mW
mA
mW
mA
mW
mA
mW
Notes: Power consumption was measured on a fully-populated 64 MB rev 3 BitsyXb system with no peripheral
connections and the following additional conditions:
19. System in Run mode at 104 MHz. Running Linux, the system is predominantly in Idle
mode (<5% CPU utilization).
20. System in Run mode at 520 MHz, running Linux. Full (95-100%) processor utilization
achieved by running multiple instances of a graphics-intensive application.
