Kontron CP383 - Manual (Page 69)

CP383 Power Consumption
ID 27784, Rev. 01 © 2004 Kontron Modular Computers GmbH Page 5 - 5
5.1.3.3 Tolerance
The tolerance of the voltage lines is described in the CPCI specification (PICMG 2.0 R3.0).The
recommended measurement point for the voltage is the CPCI connector on the CPU board.
The following table provides information regarding the required characteristics for each board
input voltage.
The output voltage overshoot generated during the application (load changes) or during the
removal of the input voltage must be less than 5% of the nominal value. No voltage of reverse
polarity may be present on any output during turn-on or turn-off.
5.1.3.4 Regulation
The power supply shall be unconditionally stable under line, load, unload and transient load
conditions including capacitive loads. The operation of the power supply must be consistent
even without the minimum load on all output lines.
Table 5-3: Input Voltage Characteristics
VOLTAGE NOMINAL VALUE TOLERANCE MAX. RIPPLE (p-p) REMARKS
5 V +5.0 VDC +5%/-3% 50 mV Not required
3.3 V +3.3 VDC +5%/-3% 50 mV Main voltage
+12 V +12 VDC +5%/-5% 240 mV Not required
-12 V -12 VDC +5%/-5% 240 mV Not required
VI/OPCI I/O voltage +3.3 VDC or +5 VDC +5%/-3% 50 mV Not required
GND Ground, not directly
connected to poten-
tial earth (PE)
Note...
Non-industrial ATX PSUs require a greater minimum load than a single CP383
is capable of creating. When a PSU of this type is used, it will not power up
correctly and the CP383 may hang up. The solution is to use an industrial PSU
or to add more load to the system.
Note...
If the main power input is switched off, the 3.3V supply voltage will not go to 0V
instantly. It will take a couple of seconds until capacitors are discharged. If the
voltage rises again before it went below a certain level, the circuits may enter a
latch-up state where even a hard RESET will not help any more. The system
must be switched off for at least 3 seconds before it may be switched on again.
If problems still occur, turn off the main power for 30 seconds before turning it
on again.