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<div>>> <font face="Helvetica">Aren't those just firecrackers?</font></div>
<div>> <font face="Helvetica">Only if you connect them backwards</font></div>
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It seems to be easier than that to make fireworks.</div>
<div>Here's a nice detailed reply on those:<br/>
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<div>http://electronics.stackexchange.com/questions/99320/are-tantalum-capacitors-safe-for-use-in-new-designs</div>
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<p><strong>Summary:</strong></p>
<p>"When used properly" tantalum capacitors are highly reliable.<br/>
They have the advantage of high capacitance per volume and good decoupling characteristics due to relatively low internal resistance and low inductance compared to traditional alternatives such as aluminum wet electrolytic capacitors.</p>
<p>The 'catch' is in the qualifier "when used properly".<br/>
Tantalum capacitors have a failure mode which can be triggered by voltage spikes only 'slightly more' than their rated value. When used in circuits that can provide substantial energy to the capacitor failure can lead to thermal run-away with flame and explosion of the capacitor and low resistance short-circuiting of the capacitor terminals.</p>
<p>To be "safe" the circuits they are used in need to be guaranteed to have been rigorously designed and the design assumptions need to be met.This 'does not always happen'.<br/>
Tantalum capacitors are 'safe enough' in the hands of genuine experts, or in undemanding circuits, and their advantages make them attractive. Alternatives such as "<strong>solid</strong> aluminum" capacitors have similar advantages and lack the catastrophic failure mode.</p>
<p>Many modern tantalum capacitors have built in protection mechanisms which implement fusing of various sorts, which is designed to disconnect the capacitor from its terminals <strong>when</strong> it fails and to <strong>limit</strong> pcb charring in <strong>most</strong> cases.<br/>
If 'when', 'limit' and 'most' are acceptable design criteria and/or you are a design expert and your factory always gets everything right and your application environment is always well understood, then tantalum capacitors may be a good choice for you.</p>
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<div>- Steve</div>
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<div style="margin:0 0 10px 0;"><b>Gesendet:</b> Freitag, 16. Dezember 2016 um 14:40 Uhr<br/>
<b>Von:</b> ijfritz@comcast.net<br/>
<b>An:</b> synth-diy@synth-diy.org, xyzzy@sysabend.org<br/>
<b>Betreff:</b> Re: [sdiy] [OT] Power supplies +5v, +/-12V for sale cheap</div>
<div name="quoted-content"><font face="Helvetica">Only if you connect them backwards (-: I've never ever had a problem with them.<br/>
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Ian<br/>
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Sent from XFINITY Connect Mobile App<br/>
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------ Original Message ------<br/>
<br/>
From: Tom Arnold<br/>
To: synth-diy@synth-diy.org<br/>
Sent: December 16, 2016 at 6:01 AM<br/>
Subject: Re: [sdiy] [OT] Power supplies +5v, +/-12V for sale cheap<br/>
<br/>
On Wed, Dec 14, 2016 at 05:05:27PM -0800, Barry Klein wrote:<br/>
> I also have some spools of tantalum capacitors for free - just pay shipping.<br/>
<br/>
Aren't those just firecrackers?<br/>
<br/>
--<br/>
-----------------------------------------------------------------<br/>
- Tom Arnold - Free Synth DIY webspace <a href="http://www.sdiy.org" target="_blank">http://www.sdiy.org</a><br/>
- SynthGeek - "...is it a virus, a drug, or a religion?"<br/>
- K6AET - Juanita Shrugs. "What's the difference?<br/>
-------------------- -- Neal Stephenson, Snow Crash<br/>
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