RE: Room Temperature to 350 Degree C Hot Air Source - for Component Testing

jw0752 — Wed, 08 Mar 2017 07:05:27 GMT

I decided to use the new tool tonight to test a couple of components. The first one is a 100 K NTC Thermistor. I have begun taking data at 20 degrees C and continued at 10 degree steps until I reached 200 degrees
C. Here is the graph for this experiment:

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The second component is an MPS2907 NPN silicone transistor. I used a cheap dynamic transistor tester that returns Type, hfe, and Vf base to emitter with each test. Here again I began at 20 degrees C and continued at 10 degree intervals until I got to 200 degrees C. In case you are interested here is the data sheet for a MPS 2907.

http://datasheet.octopart.com/MPS2907ARLRAG-ON-Semiconductor-datasheet-10126652.pdf

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The data sheet shows the rated temperature range for this transistor is -55 degrees C to 150 degrees C. Just as predicted by the Data sheet strange things happened with the hfe as we went from 150 C to 160 C.

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In this graph I have shown the change of the forward voltage drop base to emitter over the temperature range explored. Here again we see the drastic changes that occur once we get above recommended temperature. It was fun to be able to change the temperature slowly and be able to read instrumentation without the need to make quick readings. It was also nice to have reproducibility when needed.

John

RE: Room Temperature to 350 Degree C Hot Air Source - for Component Testing

DAB — Tue, 07 Mar 2017 20:38:01 GMT

Great project John.

Excellent reuse of existing components.

DAB