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AMC7908: Derating for Remote Temperature sensor Transistor

Shwetha Zacharias
Prodigy 10 points

Part Number: AMC7908

I'm asking a query for AMC7904RGER, as this particular P/N was not available in dropdown list. I'm doing MTBF and I'm not able to find the maximum current Ic through the transistor that is connected to D+ and D- pins of the IC. Pls provide Vbe or Ib or the maximum collector current that will flow through transistor during sensing of temperature so that I can find the CSR. 
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  • 0
    TI__Genius 17130 points

    Hi Shwetha,

    Please follow these conditions for remote temperature sensing transistors:

    1. Base-emitter voltage is greater than 0.25 V at 6 μA, at the highest sensed temperature.
    2. Base-emitter voltage is less than 0.95 V at 120 μA, at the lowest sensed temperature.
    3. Base resistance is less than 100 Ω.
    4. Tight control of VBE characteristics indicated by small variations in hFE (that is, 50 to 150).

    Thanks,
    Erin