A Look Inside And Component Analysis
Our main tools for disassembling PSUs are a Thermaltronics soldering and rework station and a Hakko 808 desoldering gun.
|Transient Filter||6x Y caps, 3x X caps, 2x CM chokes, 1x MOV|
|Inrush Protection||NTC Thermistor|
|Bridge Rectifier(s)||1x GBJ25L06 (600V, 25A @ 113 °C)|
|APFC MOSFETs||2x Vishay SiHG22N60E (650V, 13A @ 100 °C, 0.18 ohm )|
|APFC Boost Diode||1x Vishay 8S2TH061 (600V, 8A @ 120 °C)|
|Hold-up Cap(s)||2x Nippon Chemi-Con (400V, 390uF & 470uF or 860uF combined, 2000h @ 105 °C, KMW - KMR)|
|Main Switchers||2x Vishay SiHG20N50C (560V, 11A @ 100 °C, 0.27 ohm)|
|APFC Controller||Infineon ICE3PCS01G - CM03X|
|Switching Controller||Infineon ICE2HS01G|
|Topology||Primary side: Half-Bridge & LLC Resonant Converter Secondary side: Synchronous Rectification & DC-DC converters|
|+12V MOSFETs||6x Sinopower SM4021NAKP (40V, 100A @ 100 °C, 2.7 ohm ) @ VGS=6V)|
|5V & 3.3V||DC-DC Converters: 4x M3006D & 2x M3004D FETs PWM Controller: APW7159|
|Filtering Capacitors||Electrolytics: Chemi-Con (105 °C, KZE series) Polymers: Nippon Chemi-Con|
|Supervisor IC||Weltrend WT7502 & Weltrend WT7518|
|Fan Model||NR135P (12V, 0.22A, fluid dynamic bearing)|
|Rectifier||PFR20V45CT (45V, 20A, VF: 0.42V max @ 125 °C)|
The platform, made by Channel Well Technology (CWT), is the same as the one used in the Corsair HX750i unit, with only some component changes that lead to a lower efficiency. A digital interface allows the monitoring of the PSU's status and control of the fan along with the selection between single +12V and multi +12V modes. Analog circuits, however, control the main functions in both the primary and the secondary sides. In the primary side, a half-bridge topology is used along with an LLC resonant converter for increased efficiency; in the secondary side, a synchronous design is used along with a couple of DC-DC converters for the generation of the minor rails. In addition, Corsair used only Japanese capacitors in order to increase reliability and ensure good performance over time. (Chinese caps tend to age faster than the higher-quality Japanese ones.) This specific CWT platform doesn't use any proper heat sinks in the secondary side, which looks weird, especially in a semi-passive unit equipped with a low-speed fan. Later in this review we will take some thermal shots of the internals to check on the temperature levels in the secondary side.
In the AC receptacle we found a couple of Y caps. The second part of the transient-filtering stage continues on the main PCB with another four Y caps, three X caps, two CM chokes and an MOV. There is also an NTC thermistor providing protection against large inrush currents. Unfortunately, Corsair didn't use a relay to isolate this thermistor once the startup phase finishes, hence a small amount of energy will be lost. But most important, during a hot start the thermistor won't be able to protect the PSU efficiently in case the bulk caps are discharged, since its resistance will be low.
A single GBJ25L06 bridge rectifier is bolted onto a dedicated heat sink. It can rectify up to 25 A so it will easily handle this PSU.
In the APFC converter two Vishay SiHG22N60E FETs are used along with a single Vishay 8S2TH061 boost diode. The smoothing caps are provided by Chemi-Con (400V, 390uF & 470uF or 860uF combined, 105C, KMW & KMR series) and their combined capacity is adequate for this PSU's capacity, so we expect a pretty long hold-up time.
The primary switchers are two Vishay SiHG20N50C FETs arranged into a half-bridge topology.
In the secondary side, there isn't a proper heat sink to cool down the +12V FETs, but there are four Sinopower SM4021NAKP, which are installed on two vertical boards. Several bus bars used for power transfer purposes handle cooling of the +12V FETs. They must do a pretty good job, otherwise Corsair wouldn't provide such a long warranty. Finally, all electrolytic caps are provided by Chemi-Con and are rated at 105 degrees Celsius (221 degrees Fahrenheit).
The couple of DC-DC converters that generate the minor rails are installed on a large daughterboard. The common PWM controller is an Anpec APW7159, while on each VRM two M3006D FETs are used along with a single M3004D FET.
We found a Weltrend WT7502 installed on the main PCB and a Weltrend WT7518 installed on the modular PCB. The WT7518 is engaged when the PSU is in multi +12V rail mode. Finally, a PFR20V45CT SBR regulates the 5VSB rail.
The MCU that supports the digital interface of this PSU is a PIC32MX. This is an analog platform, but it features a digital interface, which allows the monitoring of the PSU's status along with the control of the cooling fan. Through Corsair Link you are able to monitor and log the fan speed along with the voltage and current levels of the +12V, 5V and 3.3V rails. In addition, Corsair Link informs you about the power coming in and out (in Watts), the efficiency, and allows you to enable or disable OCP on the +12V rails. From the factory the PSU comes in multi +12V rail mode.
On the front of the modular PCB we found many Chemi-Con polymer caps, which are used for ripple- filtering purposes. On the back side of the board a number of cables transfer power from the regulators to the modular sockets. Soldering quality on the board is quite good overall.
The NR135P FDB fan (12V, 0.22A) is used in many high-end Corsair models besides this one, including the HX750i. It is a low speed, silent fan supported by a very relaxed fan profile and a semi-passive mode. We managed to push it to 1200 RPM speed only during the overload test and with a very high operating temperature.