Seasonic SSP-350GT Review



The 350GT’s input filtering starts with a PCB at the AC receptacle, which contains an X-Capacitor, a coil, and four Y-Capacitors. The main PCB adds another X-Cap, 1.5 coils (one only goes over active/line, not neutral), two Y-Caps, and an MOV, bringing the total component count to two X-Caps, 2.5 coils, six Y-Caps, and one MOV, which is more than enough components. The PFC section uses a single Infineon IPI60R199CP MOSFET rated at 16A controlled by an ICE3PCS01G PFC Controller, and a 220µF Capacitor supplied by Rubycon – a reliable Japanese brand. Two Fairchild FDP18N50 MOSFETs rated at 18A are used as the switching transistors. They are controlled by an Infineon ICE2HS01G Resonant controller.


The secondary side uses both electrolytic and polymer (solid) capacitors. The electrolytic capacitors are supplied by the Japanese Nippon Chemi-con, whose capacitors are generally very reliable. The polymer capacitors are made by Enesol – a Korean company. I haven’t had a lot of experience with these capacitors, but even non-Japanese polymer capacitors are generally reliable, so I’m not going to score against them. There are also a few very small Teapo capacitors in the low stress areas.

12V Silicon_DC-DC Transistors

The 12V rail uses transistors for the rectification, as opposed to diodes. There are two NXP Semiconductors PSMN2R640YS MOSFETs rated at 100A each, as well as two 10A Schottky rectifiers. The other two rails both use DC-DC conversion from the 12V rail, using four PH7030L MOSFETs rated at 68A each. Two of them are used for the 5V rail, and the other two for the 3.3V rail. The monitoring IC used is a Hawyang HY510N. This IC doesn’t support OCP to separate the 12V rails, so this is a single rail power supply.

Soldering_Long component pin

The soldering is generally quite good, as one would expect from a company like Seasonic. There are a few component pins which could have been cut somewhat shorter, but there’s nothing seriously wrong.


The fan is made by ADDA. Thankfully, it is a ball bearing model, which are more reliable than their sleeve bearing counterparts. It has maximum speed, airflow and noise ratings of 2200RPM, 87.87CFM, and 39dB respectively. It was extremely quiet at light loads. It first became noticeable with the power supply at 250W load, and became fairly loud at full load. Below 250W, it was very quiet. The heat sinks are very small, but on an efficient 350W product, there’s hardly any heat to dissipate, so they don’t need to be big.


Pages: 1 2 3 4