3.1 Power Supply
The power supply automatically switches to either the 100-125 Vac or the
200-240 Vac range. The ac input is converted to dc outputs that supply
the system with proper operating voltages.
When the system is powered-off for 10 seconds or more and then powered-on,
the power supply generates a 'power good' signal that resets system logic.
The presence of the 'power good' signal indicates that the power supply is
operating properly and that the minimum under-voltage sense levels have
been established. This means that all system-board power requirements
have been met.
+------------------------------------------------------------------------+
¦ Output ¦ Minimum Under-Voltage ¦
¦ (Vdc) ¦ Sense Level (Vdc) ¦
+------------------------------------+-----------------------------------¦
¦ + 5.0 ¦ + 4.5 ¦
+------------------------------------+-----------------------------------¦
¦ +12.0 ¦ +10.8 ¦
+------------------------------------+-----------------------------------¦
¦ -12.0 ¦ -10.2 ¦
+------------------------------------+-----------------------------------¦
¦ ¦ ¦
+------------------------------------------------------------------------+
The 'power good' signal turns on the green power-good light on the front
of the system. If the green light is not on, the power supply is not
functioning properly.
IBM PS/2 Model 80 HMR
Power Supply
¦ Copyright IBM Corp. 1990
3.1 - 1
