Contents
- 1Introducing the Corsair CX550M
- 1.1Packaging and accessories
- 2Connectors & cabling
- 2.1Casing & cooling
- 3Input filtering
- 4Primary side
- 4.1+5 V stand-by rail
- 5Secondary side
- 5.1Build quality
- 6Load testing
- 6.1Loading +5 V SB
- 6.2Voltage hold-up time
- 6.3Combined loading
- 6.4Combined loading ripple
- 6.5Crossloading, overloading
- 6.6Crossloading, overloading ripple
- 6.7Fan speed, temperatures and noise
- 7Conclusion and evaluation
- 7.1Bonus
- 7.2Thanks
- 7.3Discussion
Primary side
The bridge rectifier has its own heatsink and it is the GBU1006 (10/220 at 600 V and 100 °C, voltage drop is 1.1 V per diode at 10 A). The two transistors in the PFC section are Fuji Electric FMV20N60S1 (20/60 A at 600 V and 25 °C, RDS(On) 0.19 Ω at 10 A) in TO-220F package. The diode is an ST Microelectronics STTH8S06D (8/60 A at 175 °C and 600 V, drop of 3.4 V at 8 A and 25 °C, 1.9 V at 125 °C) in a TO-220AC package. The PFC coil is the same one that we have been accustomed to from CWT, which encloses the winding inside a core.
The bulk cap charged from the PFC is a Nichicon GG 220 μF/400 V, which measures at 196 μF. This series has a minimum lifetime of 2000 hours at its maximum rated ripple and temperature (105 °C). As for the switchers, we have two Infineon IPA50R280CE (13/42.9 A at 25 °C and 500 V, RDS(On) 0.28 Ω at 4.2 A and 25 °C, 0.66 Ω at 150 °C) in a TO-220F package. All the PFC silicon in conjunction with the switchers use the common primary heatsink for heat dissipation.
The PFC/primary switchers driver is the known combo chip Champion Micro CM6800TX. A Su’scon SD 2.2/50 capacitor filters its power supply. There is also an SPN5003 microchip from SYNC Power which serves to reduce no-load power consumption. It comes in a SOP-8 package on the solder side of the board. The main transformer seems to use a 35mm core.
+5 V stand-by rail
The stand-by rail in the CX550M uses the On-Bright OB5269CP PWM microchip. It comes in a SOP-8 package so it is located on the solder side and drives the CET-MOS CEF04N07G transistor (4/16 A at 700 V and 25 °C, 3.3 Ω at 2 A) in a TO-220F package. It also sources its power directly from the input filtering, in front of the input rectifier. A Su’scon MF 22/50 filters its power supply from the secondary tap of the 19mm transformer.
A TO-220 rectifier with both diodes in parallel then rectifies the AC into DC. It is the MBRQ2045CT, most likely some clone of the more familiar MBR2045CT (20/150 A at 165 °C and 45 V, 0.84 V at 25 °C, 0.72 V at 125 °C). For filtering there is a Chemi-Con KY 2200/10 V capacitor as well as an Apaq (most likely AREC series) 820/6.3 polymer after the Pi coil.