Found this dead unit in an HP 6000 series desktop with first generation i3 CPU. Could not identify the manfucaturer, it is a TFX unit with UL of E314577. Being filled with Ltec and AiShi(t), who knows. I first thought it will be just the secondary caps, but the problem is worse than that.
Not sure if the unit overheated first which baked the CM6800 cap (47uF nominal, measures 52 uF and 65 ohm ) and made the single-forward FET explode, taking some ceramics with, or the other way around. Anyways, the Toshiba 2SK3878 is blasted drain to source. There are also two small THT ceramics in parallel, between the drain (and transformer center pin) and the HV input (+390 V). I can not get their values as one of them vaporised and the other is broken. Any idea? I'd guess it to be 1 or 2 kV and some very small value. I managed to desolder the second one which has the ceramic disc broken, but it seems the electrode is still attached to the actual capacitor core, which measures slightly under 1 nF. I guess this is beliavable.
So would it be safe to use two 1nF or single 2.2nF cap? I hope changing the capacitance by a tiny bit should not move the circuit balance too much. Cause if I am not mistaken, these caps are quite important as they transfer some power at the switched frequency which is 52-74 kHz for CM6800.
Not sure if the unit overheated first which baked the CM6800 cap (47uF nominal, measures 52 uF and 65 ohm ) and made the single-forward FET explode, taking some ceramics with, or the other way around. Anyways, the Toshiba 2SK3878 is blasted drain to source. There are also two small THT ceramics in parallel, between the drain (and transformer center pin) and the HV input (+390 V). I can not get their values as one of them vaporised and the other is broken. Any idea? I'd guess it to be 1 or 2 kV and some very small value. I managed to desolder the second one which has the ceramic disc broken, but it seems the electrode is still attached to the actual capacitor core, which measures slightly under 1 nF. I guess this is beliavable.
So would it be safe to use two 1nF or single 2.2nF cap? I hope changing the capacitance by a tiny bit should not move the circuit balance too much. Cause if I am not mistaken, these caps are quite important as they transfer some power at the switched frequency which is 52-74 kHz for CM6800.
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