Corsair CX-M Series 450 W Review - Ideal for Small PCs

Name: Corsair CX-M Series 450 W
Brand: Corsair
Price: 60 USD

crmaris

on Sep 8th, 2022,

in Power Supplies.

Manufacturer: Corsair

Voltage Regulation Stability & Ripple »

Component Analysis

Before reading this page, we strongly suggest looking at this article, which will help you better understand the insides of a PSU.

Corsair CX450M Parts Description
General Data
Manufacturer (OEM)	CWT
PCB Type	Single Sided
Primary Side
Transient Filter	4x Y caps, 2x X caps, 2x CM chokes, 1x MOV, 1x CAP200DG (Discharge IC)
Bridge Rectifier(s)	1x GBU808 (800 V, 8 A @ 100 °C)
Inrush Current Protection	NTC Thermistor (SCK - 2R58) (2.5 Ohm) & Relay
APFC MOSFETs	2x Silan Microelectronics SVF18N50F (500 V, 11 A @ 100 °C, Rds (on): 0.31 Ohm)
APFC Boost Diode	1x STMicroelectronics STTH8S06D (600 V, 8 A)
Bulk Cap(s)	1x Nippon Chemi-Con (400 V, 220 uF, 2,000 h @ 105 °C, KMR)
Main Switchers	2x Silan Microelectronics SVF13N50F (500 V, 8.2 A @ 100 °C, Rds (on): 0.52 Ohm)
PFC / PWM Combo Controller	Champion CM6800TX & Champion CM03X
Topology	Primary side: APFC, Double Forward Secondary side: Passive Rectification (12 V) & DC-DC converters (5 V & 3.3 V)
Secondary Side
+12 V SBRs	2x Silan Microelectronics SBD20C60T (60 V, 20 A) & 2x PFC PFR20L60CT (60 V, 20 A)
+5 V & +3.3 V	DC-DC Converters: 2x UBIQ QM3054M6 (30 V, 61 A @ 100 °C, Rds (on): 4.8 mOhm) & 2x UBIQ QN3107M6N (30 V, 70 A @ 100 °C, Rds (on): 2.6 mOhm) PWM Controller(s): ANPEC APW7159C
Filtering Capacitors	Electrolytic: 6x Elite (2 - 5,000 h @ 105 °C, ED Series.pdf]ED), 2x Nippon Chemi-Con (4 - 10,000 h @ 105 °C, KY), 1x Nippon Chemi-Con (1 - 5,000 h @ 105 °C, KZE) 6x Elite (4 - 10,000 h @ 105 °C, EY), 2x Elite (2,000 h @ 105 °C, PF) Polymer: 9x APAQ
Supervisor IC	INI1S429I - DCG
Fan Model	Hong Hua HA1225H12F-Z (120 mm, 12 V, 0.58 A, Rifle Bearing Fan)
5VSB Circuit
Standby PWM Controller	Power Integrations TNY290PG

This is the same platform I found on the CX650M. It is CWT's CSB-A design, using a combination of old and new elements. On the primary side is a double-forward topology, which is considered outdated. In contrast, the secondary side has been given a modern touch with DC-DC converters to generate the minor rails. Corsair used good caps for this price range and a rifle-bearing fan to ensure that the PSU will easily outlive the five-year warranty.

The transient filter is complete.

There is an MOV for protection against power surges. An NTC thermistor handles inrush currents. The latter has no bypass relay, usually installed in more expensive platforms.

Finding a discharge IC in a budget PSU is nice.

The single bridge rectifier can handle up to 8 A, while in the CX650M, I found a 15 A bridge rectifier.

The APFC converter uses two Silan FETs and a single boost diode. The bulk cap is by Chemi-Con. Its capacity is not high enough to reach a 17 ms hold-up time.

The primary switching FETs are installed into a double-forward topology, which is outdated, but more affordable to implement.

The combo APFC and PWM controller is a Champion CM6800TX IC—a blast from the past. A Champion CM03X supports it for the low vampire power needs of today.

The unit's main transformer provides electrical isolation between the primary and secondary sides.

A mix of FETs and SBRs regulate the +12 V rail.

Most filtering caps are by Elite, the best alternative brand to Japanese caps, along with Teapo's products. Besides electrolytic caps, nine polymer ones are also used.