Author Topic: SMD Germanium diodes?  (Read 2409 times)

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Offline awallin

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SMD Germanium diodes?
« on: November 10, 2015, 04:32:04 pm »
Hi,
These RF-detection/AM-demodulation circuits use Germanium diodes (because of their low forward voltage drop I guess)
http://electronics.stackexchange.com/questions/78530/how-can-i-tell-if-an-rf-transmitter-is-transmitting

1N270
1N34A

All google finds me is through-hole Ge diodes? Does anyone make SMD Ge diodes?
Thanks!
 

Online Vgkid

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Re: SMD Germanium diodes?
« Reply #1 on: November 10, 2015, 04:39:23 pm »
Germanium diodes were obsolete for a long time, schottkey diodes offer a low voltage drop, and are in smd package, and also in T0- cased high power varients as well.
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Offline Teledog

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Re: SMD Germanium diodes?
« Reply #2 on: November 10, 2015, 07:44:33 pm »
Does Germanium leak as much current as the Schottky?
Just askin'
 

Offline coppice

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Re: SMD Germanium diodes?
« Reply #3 on: November 10, 2015, 07:50:35 pm »
Does Germanium leak as much current as the Schottky?
Just askin'
I don't know any Schottky diodes which are as low as 0.2V forward biased that leak as little as a germanium diode at room temperature. I'm not sure about when they are warmed up. However, your wallet will leak a lot less buying the Schottky diode.
 

Offline T3sl4co1l

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Re: SMD Germanium diodes?
« Reply #4 on: November 11, 2015, 12:16:13 am »
I think they're pretty close, as far as Vf and Ir.  But the schottky will work to higher temperatures, and has no recovery time.

Back diodes are also available, which have even less Vf (which is actually Vr, because they're actually a marginal kind of tunnel diode), and are usable for very small signals.

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Offline free_electron

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Re: SMD Germanium diodes?
« Reply #5 on: November 11, 2015, 12:37:48 am »
Simp,y apply a dc bias.
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