XO DC Input
This page attempts to detail the different tests that an XO DC power input should pass.
Contents
Absolutes
These are static tests of the input protection circuitry:
Valid Input Voltage
The laptop shall operate and charge the battery when supplied with any voltage between 11V and 24V (inclusive).
Overvoltage
The laptop shall not be damaged by the application of voltages up to 40V, for any length of time.
Applying a voltage higher than 40V shall not result in fire, but may destroy the internal fuse.
Undervoltage
The laptop shall not draw power from the DC power input when supplied with voltages between 0V and 9V.
Negative Voltage
The laptop shall not be damaged by the application of a negative voltage up to -38V, for any length of time.
Applying a negative voltage larger than -38V shall not result in fire, but may destroy the internal fuse.
Maximum Power Draw
The laptop shall never draw more than 25 Watts of power from its DC power input. This is usually tested with the laptop on and running processor tests from Open Firmware, while charging a low battery (open circuit battery voltage less than 5.6V).
The actual power limit depends on the laptop model. For XO-1, this number was 17 Watts.
