Linkworld(?) LPJ19-25E
Hello again,
I've got a "Model: LPJ19-25E 3*SATA" PSU here which came with a case. (no worries, it was free
)
I only used the case because the PSU is having a "cheap" label which has got all the watt ratings on it and the chinese children that have made this unit only had to put a small sticker on it to make clear which unit it was on the list. The case is also made from very, very thin metal. It was all bent up at the place where you insert the power cord and ik could even bend the case with one finger, it is even more worse that the L&C units.
So, i've opened the casing (with very little hope) to expect a ~150W unit with no input filtering at all. But after all, it's better than i expected. So let's take a look!
Let's start with the primary filtering. This unit has got: 2 ferrite coils, 4 Y-caps, 2 X-caps and a NTC thermistor(?). Only missing a MOV here. The psu also has got a PFC coil (passive PFC) which looks like a real one, in can see some windings sitting in there. This really surprised me, a almost complete primary filtering stage, all the spots on the pcb for it are filled!
And now the primary... Because this is a 230V only PSU the primary side has only got to do 2A continuous, by the time this PSU needs 460W from the grid it should have already been exploded. The input caps are 2 200V, 470uF, 105° (LE YC) which are a bit on the small side, i doubt if they really are 470uF. This PSU doesn't have a rectifier bridge but has got 4 1N5408 (3A, 105°) diodes which should be enough. And the primary switchers are 2 D304X (12A, 400V, 100W power transistor).
The transformer is a AETOJEI33DN0011 which is probably a EI33. That will do about 250~300W.
The heatsinks on this unit are a bit mediocre, i've seen worse on some cheap units but i've also seen far better on somewhat more expensive units.
The secondary side has got 3 recitfiers;
12V: MBR30100CT (30A, 100V, Scottky
)
5V: S20C45C (20A, 45V, Scottky)
3.3V: S20C45C (20A, 45V, Scottky)
So this unit has got full Scottky, which is good. And it seems like this PSU is a 12V heavy design
And the secondary filtering: (aren't sure of which volt line they really are, but this seems the most logic way)
12V: 1x 16V 2200uF (YC)
5V: 1x 10V 2200uF (YC), 1x 10V 1000uF (YC)
3.3V: 2x 10V 1000uF (YC)
And the pwm (or supervisor?) chip is a:
Welltrend WT7520
The PSU has also got a temperature controlled fan and the thermal probe is glued to the big coil at the secondary side. But isn't it better to mount the probe to the secondary heatsink instead of the coil?
So what do you guys think about it? How much could this power supply really deliver?
I've got a "Model: LPJ19-25E 3*SATA" PSU here which came with a case. (no worries, it was free
) I only used the case because the PSU is having a "cheap" label which has got all the watt ratings on it and the chinese children that have made this unit only had to put a small sticker on it to make clear which unit it was on the list. The case is also made from very, very thin metal. It was all bent up at the place where you insert the power cord and ik could even bend the case with one finger, it is even more worse that the L&C units.
So, i've opened the casing (with very little hope) to expect a ~150W unit with no input filtering at all. But after all, it's better than i expected. So let's take a look!
Let's start with the primary filtering. This unit has got: 2 ferrite coils, 4 Y-caps, 2 X-caps and a NTC thermistor(?). Only missing a MOV here. The psu also has got a PFC coil (passive PFC) which looks like a real one, in can see some windings sitting in there. This really surprised me, a almost complete primary filtering stage, all the spots on the pcb for it are filled!
And now the primary... Because this is a 230V only PSU the primary side has only got to do 2A continuous, by the time this PSU needs 460W from the grid it should have already been exploded. The input caps are 2 200V, 470uF, 105° (LE YC) which are a bit on the small side, i doubt if they really are 470uF. This PSU doesn't have a rectifier bridge but has got 4 1N5408 (3A, 105°) diodes which should be enough. And the primary switchers are 2 D304X (12A, 400V, 100W power transistor).
The transformer is a AETOJEI33DN0011 which is probably a EI33. That will do about 250~300W.
The heatsinks on this unit are a bit mediocre, i've seen worse on some cheap units but i've also seen far better on somewhat more expensive units.
The secondary side has got 3 recitfiers;
12V: MBR30100CT (30A, 100V, Scottky
)5V: S20C45C (20A, 45V, Scottky)
3.3V: S20C45C (20A, 45V, Scottky)
So this unit has got full Scottky, which is good. And it seems like this PSU is a 12V heavy design
And the secondary filtering: (aren't sure of which volt line they really are, but this seems the most logic way)
12V: 1x 16V 2200uF (YC)
5V: 1x 10V 2200uF (YC), 1x 10V 1000uF (YC)
3.3V: 2x 10V 1000uF (YC)
And the pwm (or supervisor?) chip is a:
Welltrend WT7520
The PSU has also got a temperature controlled fan and the thermal probe is glued to the big coil at the secondary side. But isn't it better to mount the probe to the secondary heatsink instead of the coil?
So what do you guys think about it? How much could this power supply really deliver?
Attached Files
Half of the computer problems is caused by bad contacts 
.
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