(2018-03-21, 20:25)mwaters Wrote:(2018-03-21, 20:10)Dieter Wrote:(2016-06-22, 09:45)Schneid3 Wrote: Mir ist aufgefallen, dass bei vielen der Blue Stationen, so auch bei mir der, der Offset oberhalb der 0V-Linie liegt. Bitte woran kann dies liegen?
Hallo
Hast Du das Problem geloest ? Ein anderer User hat es offenbar mit PCB Reinigungspray kuriert.
Ich habe das gleiche Problem und wuerde es gerne beseitigen.
Gruss
Dieter Station (2167 in Melbourne)
19.1 through 19.3 all have this problem, which is caused by the way the controller PCB was designed. I have never heard of fixing the offset by cleaning, do you know any more details?
Unless this can be fixed in firmware, there is apparently nothing that can be done about it.
The DC offset is Normal for current BLUE controllers... It does NOT affect signal processing on the servers, and mayl be improved somewhat in later production boards. It is ignored by the server.
The offset is due to the reference voltage established on IC500, which is derived from the VDD source. IC500 effectively separates the Analog devices from the Digital Processing. This tends to minimize digital 'noise' in the supply for the analog amplifier chains. The Analog portion uses VDD, and VGND. The digital processing, uses 3V3 and GND, with a reference derived from 3V3 volt supply... this slight difference in circuit 'dc levels' produces the offset artifact induced in the ADCs.
No problem,just irritating
Cheers!