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Electronics => Repair => Topic started by: 13hm13 on May 31, 2019, 10:38:28 pm

Title: SB1040 3-pin rectifier (substitutes?)
Post by: 13hm13 on May 31, 2019, 10:38:28 pm
I have a 5V (3amp) wallwart adapter that seems to have blown its SB1040.
It's a 3-pin device with the CENTER pin not used (cut out)

(https://cdn.shopify.com/s/files/1/0075/8726/6678/products/14955_468x539.jpg)

From the pic, note how the didoes are facing each other.
I don't have any 3-pin devices like thin in my bin, but I have plenty of std. didoes

Because all pins show short (0 ohms) with respect to each other (defect), I'm not sure that center pin is connected to ground. The heatsink is soldered to ground on the PCB.

Thx!
Title: Re: SB1040 3-pin rectifier (substitutes?)
Post by: Yansi on May 31, 2019, 10:44:16 pm
Switchmode or linear wallwart? From the rating (3A 5V) guessing it is a modern switchmode adapter.
Don't mess with neither of those, unless properly trained and very aware of what ya doing there!

The center pin is definitely connected to the heatsink tab and more than likely it won't be connected to ground, but +5Vout.

Whats the problem obtaining (buying) a replacement diode? These should cost just pennies, "1040" schottky diodes are more than abundant, can be even salvaged from an old beaten PC power supply.

Title: Re: SB1040 3-pin rectifier (substitutes?)
Post by: 13hm13 on May 31, 2019, 10:57:15 pm
Thx for the feedback.

Actually, the issue is resolved as there was another problem with 120v socket (power) strip. Doh!

Yes, its SMPSU from company KEIC. Nice construction on the inside ... layout, parts quality, etc. Very handy for SBC and portable HDDs.

The nearest electronics store is 5 miles away. I'm sure they'd have a cheap replacement. But I'm not regular repairer so a bit of hassle.