Page 3 - Physical Look - Inside
As always, we opened up our Seasonic Platinum 1000W power supply to take a detailed look at what is going on inside. Please note that doing this at home will void your 7-year warranty, thanks to the warranty seal Seasonic applied over one of the attachment screws. But for the benefit of you, we cracked ours open so you don't need to, haha. There are no user serviceable parts inside.
Disassembling the Seasonic Platinum 1000W is quite a bit more complicated than many PSUs I have reviewed in the past. While most power supplies uses a three sided shell cover that provides an almost immediate tour to majority of the internal components, Seasonic's implementation is a combination of several pieces assembled together like a jigsaw puzzle -- removing one thing will require the disconnection of another. But before we get to that, let's get a few things out of the way first. Built by Seasonic themselves (Not surprising), our photo above shows an overhead view of the its internal components. At first glance, the build quality appears to be excellent, as one would expect from the company. It is also surprisingly simple for a kilowatt rated Platinum certified PSU; the components are well organized for optimal cooling and reduced heat congestion as well. There are three heatsinks inside the power supply, with all of them finned at the top. They are all very small, as you can see in our photo above.
After fifteen minutes and more than a dozen of screws later, we finally got the frame out. The transient filter stage is the first input stage of a computer power supply, so we will take a look at that first. Seasonic has done a great job in the past to make sure their power supplies met or exceeded the recommended requirements, and the Platinum series is certainly no exception. The Seasonic Platinum 1000W has two ferrite coils, two chokes, one metal oxide varistor, two metalized polyester X-capacitors, and six ceramic Y-capacitors. That is two times as many X capacitors and three times as many Y capacitors than recommended. Considering how many modern day PSUs have missing MOVs, I am happy to see it here, as this component is used to stabilize spikes from the AC line.
On the primary side, we can see three Japanese made Nippon Chemi-Con capacitors connected in parallel. Japanese made capacitors are usually what we expect from something in this price range, so this is nothing surprising. Our 1000W version of Seasonic's Platinum incorporates three 330µF x 420V capacitors for a total capacitance equivalence of a single 990µF x 420V capacitor (Remember that values add up when capacitors are hooked up in parallel, unlike resistors). These units are rated at 105c; whereas more value oriented power supplies usually use 85c rated capacitors.
The active PFC circuit featured on the Seasonic Platinum 1000W uses two Cree Inc. C3D10060G silicon carbide Schottky diodes, and is controlled by a Champion CM6901 resonant controller. With zero voltage switching, it greatly reduces power loss in this area. At 115V, the maximum rectified forward current capacity with heatsink is 10A for each diode, so you can theoretically pull up to 2300W (10A * 2 diodes * 115V) from the bridge rectifier at 100% efficiency -- of course, this is limited by the fact that it is not 100% efficient, and also neglects the fact that not every component in the system are able to keep up. Two Infineon IPW60R199CP power MOFSET transistors are used on the active PFC circuit on the Seasonic Platinum 1000W power supply. Four Infineon IPP60R190C6 power transistors are attached to a dedicated heatsink. Each Infineon IPW60R199CP MOFSET can deliver up to 10A at 100 degrees Celsius continuously. These transistors present a maximum resistance of 0.199 ohm when turned on; with a typical resistance of 0.180 ohm according to the manufacturer's data sheet. The Infineon IPP60R190C6 MOSFETs can deliver up to 12.8A at 100 degrees Celsius continuously; with a maximum resistance of 0.19 ohm, and a typical resistance of 0.17 ohm. This on characteristic is called Static Drain-Source On-Resistance, or commonly abbreviated as RDS(on). The more efficient the component is, the lower the RDS(on) value, since it wastes less power with lower resistance.
On the secondary side, we can see more Nippon Chemi-Con 105c capacitors. I am pleasantly surprised by this, as most companies usually resort to cheaper Taiwanese 85c units for secondary capacitors. As with modern high efficiency power supplies, all rectifiers produces the +12V out -- while the +5V and +3.3V outputs are generated from the +12V output using a DC to DC converter within the power supply unit. An Infineon CoolSET Q1 ICE2QR4765 offline SMPS quasi-resonant PWM controller with integrated power IC can be seen adjacent to the vertical PCB.
The DC-to-DC converter has one ANPEC APW7159 synchronous buck PWM controller and eight Infineon OptiMOS 3 BSC018N04LS power transistors for its rectification and DC +3.3V/+5V/+12V output process. The BSC018N04LS MOFSETs' maximum drain current is 10A at both 25c and 100c, pulsed drain current of 400A at 25c, with an RDS(on) value of 0.0018 ohm. Meanwhile, a Silicon Touch PS232F IC provides over/under current and over/under voltage protection on the vertical PCB. A National Semiconductor LM393 voltage comparator is found in the same area.
At the back, we have a large daughterboard covering the entire rear panel for the modular cable sockets. All modular sockets at the bottom are soldered directly to the main PCB after the secondary stage, with one thick cable and two thinner ones providing the +12V output at the upper sockets to reduce power transmission loss. This is completed in conjunction with the minor rail generation done by voltage regulator modules on the modular PCB to further improve efficiency. The output connector configuration can be seen on the previous page. Overall, the internal build quality of Seasonic's Platinum 1000W power supply is top notch in almost every way -- nothing short of what we would expect from a flagship product from the company. Components are arranged beautifully for optimal cooling with almost no wires running around inside, and solder points on its green PCB is very clean in general. I would say the Seasonic branded, Seasonic built Platinum 1000W is simply excellent with regards to the selection of components used under the hood.
Lastly, we see a modestly sized 120mm fan that provides cooling to the Seasonic Platinum 1000W's internal components. It is connected to the mainboard using a 2-pin connector. Although it is not the largest fan you can fit in a standard ATX power supply, an overhead design provides lots of airflow at lower speeds for quiet operation in most cases. Sanyo Denki is the fan OEM, with San Ace 120 9S1212F404 as the model number, as shown in our photo above. This is the same ball bearing fan used in the Seasonic S12D 850W, as well as many recent Seasonic power supplies. Further research indicates the 9S1212F404 is specified at 0.19A for a maximum of speed of 2200 rpm. The rated airflow is 70.6 CFM and 30.0 Pa static pressure at 30.0 dB of noise. San Ace fans aren't exactly known for their quiet operation, but they are capable of efficiently moving a lot of air. As far as implementation is concerned, it will remain off for the most part -- and even when it is on, it will be running at low speeds, so noise is not going to be a problem at all.