Good morning
I'm working on a Wolfram AW250.4. There are diodes that are marked A2 in one amp... and when I went to pull couple donors from another board... those are marked as W8.
In looking these up... A2 diode seems to be a 1N4148W(S) fast switching 75v 150ma diode.
But the W8 all I can find on it is BZT52?? A zener diode?
Am I looking at the wrong part number? They are in the exact same locations between both amps... one uses A2... the other W8...
I can order the 1N4148W but not sure what or why the W8...
I'm working on a Wolfram AW250.4. There are diodes that are marked A2 in one amp... and when I went to pull couple donors from another board... those are marked as W8.
In looking these up... A2 diode seems to be a 1N4148W(S) fast switching 75v 150ma diode.
But the W8 all I can find on it is BZT52?? A zener diode?
Am I looking at the wrong part number? They are in the exact same locations between both amps... one uses A2... the other W8...
I can order the 1N4148W but not sure what or why the W8...
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A2 is a zener diode; 5.1v 150mW.
W8 is also a zener diode and the value depends upon the package type and size; SOD323 is 5.1v 200mW, SOD123 is 4.7v 200mW and SOT89 is 3.9v 1W.
Hope that helps.
W8 is also a zener diode and the value depends upon the package type and size; SOD323 is 5.1v 200mW, SOD123 is 4.7v 200mW and SOT89 is 3.9v 1W.
Hope that helps.
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Search for that amp model on this forum. I think someone here had a diagram for it. They may not want to post it but they would be able to give a definitive answer.
Aren't those fairly large diodes, like those used to charge the high-side of the IC?
Aren't those fairly large diodes, like those used to charge the high-side of the IC?
Thanks. I'll search more. They seem super small to me. Only 1.65mm x 1.3mm x 0.8mm
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The only threads that show for Wolfram or AW250.4 are my 2. It's possible it was another amp with similar design though... I'll look through the threads in a bit.
Thanks Perry
Thanks Perry
Look up the iraudamp5 - IRS2092S.pdf and iraudamp9 - IRS2092S.pdf files in the tutorial. Then search for VAA or VSS. They are the ±5v supplies. Those designs use something a bit fancier but you'll see what you're dealing with.
You can remove the Zeners from the other sections, insert a 1k resistor in series with the diode (out of the circuit) and see where it begins to break down. Meter across the diode and increase voltage slowly until you see it stop climbing.
You can remove the Zeners from the other sections, insert a 1k resistor in series with the diode (out of the circuit) and see where it begins to break down. Meter across the diode and increase voltage slowly until you see it stop climbing.
VRef for the 2092S is 5.1v... so I'm assuming either will work? But the A2 zener impedance is 80 ohms but a 2% tolerance on voltage.. the W8 is 60 ohms with 5% tol on voltage. I'll just get some of both, and replace whatever they used factory.
A2 - https://www.mouser.ca/ProductDetail/755-UDZSTE-175.1B/
W8 - https://www.mouser.ca/ProductDetail/Taiwan-Semiconductor/BZT52C5V1S-RR/?qs=SikLhao2tv8Nli4uX9X3sQ==
Thanks! If anyone happens to find that post of info on this kind of circuit please link it. Thanks!!
A2 - https://www.mouser.ca/ProductDetail/755-UDZSTE-175.1B/
W8 - https://www.mouser.ca/ProductDetail/Taiwan-Semiconductor/BZT52C5V1S-RR/?qs=SikLhao2tv8Nli4uX9X3sQ==
Thanks! If anyone happens to find that post of info on this kind of circuit please link it. Thanks!!
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