Kontron CP3002, Руководство пользователя

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Power Considerations CP3002
Page 5 - 4 ID 1042-9252, Rev. 2.0
P R E L I M I N A R Y
5.1.2 Backplane
Backplanes to be used with the CP3002 must be adequately specified. The backplane must
provide optimal power distribution for the +3.3 V and +5 V power inputs.
Input power connections to the backplane itself should be carefully specified to ensure a mini-
mum of power loss and to guarantee operational stability. Long input lines, under dimensioned
cabling or bridges, high resistance connections, etc. must be avoided. It is recommended to
use POSITRONIC or M-type connector backplanes and power supplies where possible.
5.1.3 Power Supply Units
Power supplies for the CP3002 must be specified with enough reserve for the remaining sys-
tem consumption. In order to guarantee a stable functionality of the system, it is recommended
to provide more power than the system requires. An industrial power supply unit should be able
to provide at least twice as much power as the entire system requires. An ATX power supply
unit should be able to provide at least three times as much power as the entire system requires.
As the design of the CP3002 has been optimized for minimal power consumption, the power
supply unit must be stable even without minimum load.
Where possible, power supplies which support voltage sensing should be used. Depending on
the system configuration this may require an appropriate backplane. The power supply should
be sufficient to allow for backplane input line resistance variations due to temperature changes,
etc.
5.1.3.1 Start-Up Requirement
Power supplies must comply with the following guidelines, in order to be used with the CP3002.
• Beginning at 10% of the nominal output voltage, the voltage must rise within
> 0.1 ms to < 20 ms to the specified regulation range of the voltage. Typically:
> 5 ms to < 15 ms.
• There must be a smooth and continuous ramp of each DC output voltage from
10% to 90% of the regulation band.
• The slope of the turn-on waveform shall be a positive, almost linear voltage increase and
have a value from 0 V to nominal Vout.
5.1.3.2 Power-Up Sequence
The +5 VDC output level must always be equal to or higher than the +3.3 VDC output during
power-up and normal operation.
Both voltages must reach their minimum in-regulation level not later than 20 ms after the output
power ramp start.
Note ...
Non-industrial ATX PSUs may require a greater minimum load than a single
CP3002 is capable of creating. When a PSU of this type is used, it will not
power up correctly and the CP3002 may hang up. The solution is to use an
industrial PSU or to add more load to the system.