VIPER Technical Manual

Power and power management

 

 

Example 3: VIPER [Windows CE] at 400MHz in power saving mode + LCD with backlight on + 64MB FlashDio™ USB memory stick

In this case, the power consumed by the respective categories is:

VIPER current (Windows CE default) while idle

= 334mA ±3mA - 9mA

 

= 325mA ±3mA.

VIPER current (Windows CE default) while active

= 334mA + 99mA

±20mA

= 433mA ±20mA.

 

Power saving = 0mA.

 

External peripheral current (USB memory stick quiescent)

= 650mA (LCD) + 75mA

 

= 725mA.

External peripheral current (USB memory stick read)

= 650mA (LCD) +

121mA

= 771mA

 

Therefore, the estimated VIPER current while idle (min) is:

 

325mA ±3mA + 725mA

 

= 1050mA, ±3mA (5250mW, ±15mW).

 

and the estimated VIPER current while active and reading from USB memory stick (max) is:

433mA ±20mA + 771mA

= 1204mA, ±20mA (6020mW, ±100mW) .

© 2007 Eurotech Ltd Issue E

80