Today we’ll be looking into the Netgear Storage Central Turbo SC101T NAS which is a 2 bay NAS with Gigabit Ethernet. It has a date code of 2006/43rd week.
A few screws later and the side panels removed, we’re in.
The 2 hard drives go in the front and we’ve got the PCB at the back with fan near the center top.
The board has 4 SMPS, 3 voltage regulators with one of them being a Intersil dual regulator in a SOIC package 6549CBZ. We’ve got a connector to the front LEDs, fan and another connector which isn’t been used for anything – so likely a test connector.
Marvel Feroceon Storage Networking SoC
The main chip which runs up to 500MHz, DDR1/2 SDRAM support, supports to 2x SATA 2.0 devices, 2 USB ports, PCI Express, PCI and 1 gigabit ethernet. It’s running with an 25MHz crystal oscillator.
88F5182
MIRA 256Mb DDR SDRAM
P2S56D40CTP
Marvel Gigabit Ethernet Transceiver
88E1111
Marvel 32Mbit Flash Memory
29LV320CBTC-70G
TI Octal D-Type Latch
There are 3 of these on board but it isn’t too clear they are being used for.
LVC373A
Fairchild unknown chip
Labelled with PG9SD 123A
On the LED board, it looks like we’ve got a Microchip TC651BEV which is an over temperature sensor and a fan controller. A little odd that they would put this on the LED board but possibly because it’s closer to the hard drives for temperature sensing.
And that’s all.
HI, at the moment I’m trying to repair one exactly like the above mentioned. The problem that I’m facing is that I just replaced the 25P03LG mosfet which was found faulty. but apparently there is a short somewhere else. When the mosfet is not connected the circuit seems that its not shorted but exactly as I reconnect it the power supply signals a short and the mosfet itself start to really heat up. I don’t know if you can help me on this matter?
Regards Mark
Hi Mark,
It looks like that P mosfet is responsible for switching the whole unit on or off, so it could really be anything causing the short. Do you have a IR temp sensor available as it could help find the component that is shorted.
Have you checked the different voltage rails to see if any rail is shorted (when power is off) and also to see what voltage they are at when powered on? The 3x small DC-DC near by should output 1.2V, 2.5V and 5V.
Hi Alex thanks for your reply. I shall check and verify.
I had (starting from capacitor’s side) 0v, 11.2v, 2.1v.
Just to confirm we are on the same page I’ve written the output on each cap I measured. If yours isn’t the same, something is loading it down.
Mine are all 11.5v…
To be totally clear… I Tried again risking my CMOS… First I tried with the Cmos disconnected and the above result was obtained… then I got 1.6, 2.2, 2.2