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I would like to test a few diodes electrical characteristics at their device low limit, ambient, and device high limit temperatures.

I was thinking of using a Peltier element with a heat sink, but I'm not too sure how this would look like with sending current pulses.

The Peltier element could be put in a thermal chamber, but wouldn't the length of test leads cause interference with impedance and such?

The diodes of test are listed here:

MBRS340T3G
MBRS360T3G
BSS123
MBRS130LT3G
MBRS3200T3G

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  • \$\begingroup\$ Are you looking for a solution for inbound test or simply want to test a few hand selected components? \$\endgroup\$ – Jack Creasey Oct 10 '17 at 17:03
  • \$\begingroup\$ inbound test. Does my question make sense or do I need to clarify further? \$\endgroup\$ – Donald Krambeck Oct 10 '17 at 17:12
  • \$\begingroup\$ Do you have a TEC controller to provide the correct current to the Peltier device depending on feedback from a temperature sensor? Which one are you using? \$\endgroup\$ – The Photon Oct 10 '17 at 17:17
  • \$\begingroup\$ I'm not sure if I have one at work, but I would assume no. If I can provide a set up using a TEC Controller at a reasonable price, I could try to get permission to purchase the TEC controller and peltier element. I just didn't want to buy anything prior to finalizing on a working test set up. \$\endgroup\$ – Donald Krambeck Oct 10 '17 at 17:21
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If you are anticipating an inbound test environment (hundreds to thousands of devices) then I assume you want to test in tape/reel mount with pin probes. I'd suggest:

  1. Ambient tests simply at room temperature
  2. Room temperature environment High temperature test using self heating (perhaps use a thermal imager to measure temperature if you want close spec)
  3. Low temperature testing may be the largest challenge, but perhaps you could use a compressed air cooler. These can get you to -40 degC (with pre-cooled air supply) and I've used them for high power cpu tests with no heatsinks, holding a cpu at about 0 DegC. for example Exair cold gun

If you are testing complete reels, then of course you could use a small environmental chamber, fitting your reel to reel testing station inside.

The use of a peltier is possible, though I think it would slow your testing rate.

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  • \$\begingroup\$ I apologize, I was not familiar with the term inbound test. I am just sampling 5-6 of each of the above listed diodes. \$\endgroup\$ – Donald Krambeck Oct 10 '17 at 19:39
  • \$\begingroup\$ the low/high limit temps for the diodes are around -55C to 125C. Is this realistic from a Peltier element? \$\endgroup\$ – Donald Krambeck Oct 12 '17 at 19:19
  • \$\begingroup\$ You certainly can achieve 125 degC, though likely with 2 in series (thermally) but achieving -55 degC may be more of a challenge. Most modules are only rated to -40 degC. tetech.com/peltier-thermoelectric-cooler-modules/… \$\endgroup\$ – Jack Creasey Oct 12 '17 at 20:14
  • \$\begingroup\$ Honestly as long as I can get relatively close to the low limit temperature of the diodes, that will work perfectly. Thanks for the link! \$\endgroup\$ – Donald Krambeck Oct 13 '17 at 13:12
  • \$\begingroup\$ I will look into options as to how to cascasde two of them. Thanks Jack \$\endgroup\$ – Donald Krambeck Oct 13 '17 at 14:24

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