Substitute for Diode BAV199

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Crazyboss
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Substitute for Diode BAV199

Post by Crazyboss »

Hello

Need some help from your electronic guys :)

Can I used two 1n4148 diods instead of one BV199 ?
//CLAUS - Webmaster at www.mtxworld.dk
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1024MAK
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Re: Substitute for Diode BAV199

Post by 1024MAK »

In what circuit and in which position is this for?

Mark
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Bill B
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Re: Substitute for Diode BAV199

Post by Bill B »

Looking at the data sheets, it seems to me that there are two significant differences between the BAV199 and a pair of 1N4148:
  • The BAV199 diodes have a reverse leakage current of only 5nA, as opposed to 25nA for the 1N4148.
  • The two diodes in a BAV199 will be very closely matched, and thermally coupled, so will have almost identical characteristics.
So if either of these characteristics are important in the circuit, then not a good idea to substitute.

If, however, the BAV199 is used just because it is a convenient small package for two diodes, then probably OK. The voltage and power ratings of the 1N4148 should be adequate.
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Crazyboss
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Re: Substitute for Diode BAV199

Post by Crazyboss »

Bill and Mark, I will bring the schematics for the Memofest, then you can help me to understand it :)
Its quite simple, circuit.
//CLAUS - Webmaster at www.mtxworld.dk
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