Part Analysis
| General Data | |
| Manufacturer (OEM) | Lite-On |
| PCB Type | Single-Sided |
| Primary Side | |
| Transient Filter | 2x Y caps, 2x X caps, 2x CM chokes, 1x MOV |
| Inrush Protection | NTC Thermistor SCK-056 5Ω @ 25°C & Relay |
| Bridge Rectifier(s) |
2x GBU25KH (800V, 25A @ with heatsink°C)
|
| APFC MOSFETs |
2x Infineon IPW60R120P7 (650V, 16A @ 100°C, Rds(on): 0.120Ohm)
|
| APFC Boost Diode |
1x NXPSC06650X (650V, 6A @ 175°C)
|
| Bulk Cap(s) |
1x TK (450V, 680 , 3000h @ 105°C, LGWA)
|
| Main Switchers |
2x Infineon IPW60R180P7 (650V, 11A @ 100°C, Rds(on): 0.180Ohm)
|
| Topology |
Primary side: APFC, Half-Bridge & LLC converter
Secondary side: Synchronous Rectification & DC-DC converters |
| Secondary Side | |
| +12V MOSFETs | 6x |
| 5V & 3.3V | DC-DC Converters: 2x Fairchild FDD8896 (30V, 94A @ 175°C, Rds(on): 1.4mOhm) 2x Fairchild FDD8880 (30V, 58A @ 175°C, Rds(on): 1.4mOhm) PWM Controller(s): ANPEC APW7159C |
| Filtering Capacitors | Electrolytic: 12x Jamicon TK series (2,000 @ 105°C, LWK), Polymer: 19x |
| Supervisor IC | Weltrend WT7527RA |
| Fan Model | Yate Loon (D14SH-12) (140mm, 12V, 0.7A, Hydraulic Dynamic Bearing Fan) |
| 5VSB Circuit | |
| Rectifier |
1x PJ3081
|
| Standby PWM Controller | Excelliance MOS EM85690 |
We find the same purple heatsinks in the higher capacity models but with much smaller dimensions since this unit’s thermal loads are lower. As expected, the platform’s design differs from the 1050W and 1250W models, using cables to connect the modular PCB to the main one instead of PCB traces, which wouldn’t affect airflow and would have lower resistance because of the shorter path. Using cables to connect parts within a power supply is not elegant. It reminds me of older platforms. Thankfully, the cables are on the side, only blocking airflow to four polymer caps, which have increased temperature tolerance.
The main transformer is small but can handle the required power without issues. On the primary side, besides the APFC converter, two FETs, arranged in a half-bridge topology, chop the incoming signal to feed the main transformer, which provides power to the secondary side. An LLC resonant converter is also used to minimize switching losses. Six FETs handle the 12V rail on the secondary side, and two DC-DC converters generate the minor rails.
As in the other Lite-on-made units I evaluated, the soldering quality is impeccable, and the FETs are high quality. Some may frown upon the view of the TK (Toshin Kogyo Co., Ltd) caps, which are Japanese on paper but are made in China, like most Japanese capacitors nowadays. I recently learned that TK caps are made by ChengX (Chengxing), which also makes caps for Panasonic, Teapo, and Rubycon. This capacitor maker belongs to the Chinese government, so I expect its manufacturing equipment to be advanced. Lastly, the filtering caps on the secondary side are by Jamicon, so they are of decent quality.
Like its 850W sibling and unlike the higher models of the family, the 750W model uses a low-end Yate Loon fan. CM should rethink this choice and immediately change to a Hong Hua fan.
