Hi all,
I'm looking for advice in the selection of a replacement for a defective KMB2D0N60SA mosfet. This one is used in a standby PSU, where it controls external current limit of a TOP258MG off-line switcher. I don't know why and how the mosfet died. I measured the other components on the PCB with my DMM, and they all appear to be OK.
Finding a source for this mosfet proves to be quite a challenge. I either end up with brokers in Asia that only do deals in large quantities or a webshop that charges $ 10 shipping for a part costing 20 cents
So, I started looking for a readily available substitute. Luckily I could find its datasheet, which showed it to be a relatively standard run-of-the-mill N-channel type. Using this datasheet and alltransistors.com/mosfet/crsearch.php's mosfet cross-reference search engine, I found a number of more-or-less equivalent types. The fact that the replacement needs to come in a SOT23 package did complicate finding a suitable one a bit. I ended up with a Vishay part (Si3208 to be more precise) that (according to its datasheet) appears to fit the original mosfet's specs largely.
Before ordering, I would like the BadCaps experts' opinion, though, to make sure this really is a proper replacement.
The specs of the original part are:
Vds = 60V
Vgs = +/- 20V
Vth = 1.5V
Id = 2A
Is = 1A
Idss = 0.5 uA @ Vgs = 0V, Vds = 60V
Igss = 100 nA
Pd = 1.25W
Rds(on) = max. 160 mOhm, typ. 125 mOhm @ Vgs = 10V, and max. 220 mOhm, typ. 155 mOhm @ Vgs = 4.5V
Id(on) = 6A @ Vgs = 10V, Vds => 4.5V, and 4A @ Vgs = 4.5V, Vds => 4.5V
The Vishay Si3208 looks like a good substitute. Its specs are:
Vds = 60V
Vgs = +/- 20V
Vth = 1V
Id = 2.3A
Is = 1.39A
Idss = 1 uA @ Vgs = 0V, Vds = 60V
Igss = 100 nA
Pd = 1.66W
Rds(on) = max. 156 mOhm, typ. 130 mOhm @ Vgs = 10V, and max. 192 mOhm, typ. 160 mOhm @ Vgs = 4.5V
Id(on) = 8A @ Vgs = 10V, Vds => 5V
The Vishay part has better specs in general, but Rds(on), Vth and Idss differ with the original part. I don't know if these have to be completely identical or closer to the original part's values.
What do your expert eyes think, can I safely use a Si3208 as a replacement?
re-atari
I'm looking for advice in the selection of a replacement for a defective KMB2D0N60SA mosfet. This one is used in a standby PSU, where it controls external current limit of a TOP258MG off-line switcher. I don't know why and how the mosfet died. I measured the other components on the PCB with my DMM, and they all appear to be OK.
Finding a source for this mosfet proves to be quite a challenge. I either end up with brokers in Asia that only do deals in large quantities or a webshop that charges $ 10 shipping for a part costing 20 cents
So, I started looking for a readily available substitute. Luckily I could find its datasheet, which showed it to be a relatively standard run-of-the-mill N-channel type. Using this datasheet and alltransistors.com/mosfet/crsearch.php's mosfet cross-reference search engine, I found a number of more-or-less equivalent types. The fact that the replacement needs to come in a SOT23 package did complicate finding a suitable one a bit. I ended up with a Vishay part (Si3208 to be more precise) that (according to its datasheet) appears to fit the original mosfet's specs largely.
Before ordering, I would like the BadCaps experts' opinion, though, to make sure this really is a proper replacement.
The specs of the original part are:
Vds = 60V
Vgs = +/- 20V
Vth = 1.5V
Id = 2A
Is = 1A
Idss = 0.5 uA @ Vgs = 0V, Vds = 60V
Igss = 100 nA
Pd = 1.25W
Rds(on) = max. 160 mOhm, typ. 125 mOhm @ Vgs = 10V, and max. 220 mOhm, typ. 155 mOhm @ Vgs = 4.5V
Id(on) = 6A @ Vgs = 10V, Vds => 4.5V, and 4A @ Vgs = 4.5V, Vds => 4.5V
The Vishay Si3208 looks like a good substitute. Its specs are:
Vds = 60V
Vgs = +/- 20V
Vth = 1V
Id = 2.3A
Is = 1.39A
Idss = 1 uA @ Vgs = 0V, Vds = 60V
Igss = 100 nA
Pd = 1.66W
Rds(on) = max. 156 mOhm, typ. 130 mOhm @ Vgs = 10V, and max. 192 mOhm, typ. 160 mOhm @ Vgs = 4.5V
Id(on) = 8A @ Vgs = 10V, Vds => 5V
The Vishay part has better specs in general, but Rds(on), Vth and Idss differ with the original part. I don't know if these have to be completely identical or closer to the original part's values.
What do your expert eyes think, can I safely use a Si3208 as a replacement?
re-atari
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