Eurotech Appliances VIPER / VIPER-LITE PXA255 - Manual (Page 78)

VIPER Technical Manual Power and power management
© 2007 Eurotech Ltd Issue E 78
External peripheral device power estimations
Take into account any external peripherals for your application, such as:
• USB devices: keyboard, memory stick and mouse.
• CompactFLASH socket: CompactFLASH memory or Microdrive.
• Flat panel display: TFT logic + backlight, STN logic + backlight + bias voltage.
The table below gives examples of addition current/power from external peripheral
devices:
Device Part number Condition
Additional
current
Additional
power
Inserted, (no access) 1mA 5mW
32MB Sandisk
CompactFLASH
SDCFB-32-101-80
Reading constantly 48mA 240mW
Inserted, (no access) 75mA 375mW
64MB FlashDio™
USB memory stick
FDU100A
Reading constantly 121mA 605mW
LCD and backlight on 650mA 3250mW NEC 5.5” LCD +
Inverter (as used
with VIPER-ICE)
NL3224BC35-20
+ 65PW31
LCD on and backlight off 291mA 1455mW
For devices using the 3.3V supply from the CompactFLASH socket and FPD
logic supply, use 92% as the regulator efficiency.