VIPER
Power and power management
Power estimate examples
Example 1: VIPER in standby (microprocessor in sleep mode and every power saving option enabled)
In this case, the power consumed by the respective categories is:
VIPER current (norm) = 405mA ±5mA
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Processor current saving = 62mA
On board peripheral current saving = 236mA
External peripheral current = 0mA
Applying the formula shown on page 52, the estimated VIPER current in standby is:
405mA ±5mA - 62mA - 236mA + 0mA
= 107mA ±5mA (535mW ±25mW).
Example 2: VIPER at 400MHz with 100MHz external LCD with backlight on
In this case, the power consumed by the respective categories is:
VIPER current (norm) = 405mA (tolerance accounted for in CPU current saving)
Processor current saving = -92 ±15mA
On board peripheral current saving = 0mA
External peripheral current = +650mA
Therefore, the estimated current the VIPER is using is:
405mA + 92mA ±15mA - 0mA + 650mA
= 1147mA, ±15mA (5735mW, ±75mW).
© 2004 Arcom Issue H
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