How to Test Transistors and FETs - Revision history

Aplstudent at 20:06, 5 June 2017

2017-06-05T20:06:10Z

2017-05-26T18:16:12Z

2017-05-26T18:12:43Z

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2017-05-26T18:03:52Z

2017-05-26T18:03:27Z

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 thing for N-FETs and P-FETs. Sometimes on the FET graph more than one curve will appear of the shape shown. That is not a problem, it is not like the transistor where all
 of the lines are close together and seemingly heading in the same direction. A big part of this is guess and check. There are no exact settings that work every time for
-every device. If on the first run, the graphs don't look like the ones above, go back and change the settings a little bit and check it again. If, after many trials of
+every device. If on the first run, the graphs don't look like the ones above, go back and change the settings a little bit and check it again. If you are still having troubles
-different settings, you can't reproduce a similarshape as the graphs above, then you may have a bad transistor or FET.
+getting the graphs to look like those above, test another component of the same type. If the graphs look the same, then both components are probably good. If they are different,

@@ Line 39: / Line 39: @@
-Above are the results you hope to see from a transistor and a FET. NPN and PNP transistors should have similar looking graphs when compared to each other and the same
+Above are the results you hope to see from a transistor and a FET. NPN and PNP transistors should have similar looking graphs when compared to each other, and the same
-thing for N-FETs and P-FETs. A big part of this is guess and check. There are no exact settings that work every time for every device. If on the first run, the graphs
+thing for N-FETs and P-FETs. Sometimes on the FET graph more than one curve will appear of the shape shown. That is not a problem, it is not like the transistor where all
-don't look like the ones above, go back and change the settings a little bit and check it again. If, after many trials of different settings, you can't reproduce a similar
+of the lines are close together and seemingly heading in the same direction. A big part of this is guess and check. There are no exact settings that work every time for
-shape as the graphs above, then you may have a bad transistor or FET.
+every device. If on the first run, the graphs don't look like the ones above, go back and change the settings a little bit and check it again. If, after many trials of

← Older revision		Revision as of 18:12, 26 May 2017
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	[[File:Tresults.JPG\|left\|thumb\|Results from a working NPN transistor\|400px]] [[File:Fresults.JPG\|center\|thumb\|Results from a working P-FET\|400px]]		[[File:Tresults.JPG\|left\|thumb\|Results from a working NPN transistor\|400px]] [[File:Fresults.JPG\|center\|thumb\|Results from a working P-FET\|400px]]
		+

	Above are the results you hope to see from a transistor and a FET. NPN and PNP transistors should have similar looking graphs when compared to each other and the same		Above are the results you hope to see from a transistor and a FET. NPN and PNP transistors should have similar looking graphs when compared to each other and the same

@@ Line 35: / Line 35: @@
 == Getting Results ==
 Once all of your settings are correct, press the start button to run the machine. When you do this, a graph will appear and start tracing curves.
 [[File:Tresults.JPG|400px]]  [[File:Fresults.JPG|400px]]

@@ Line 35: / Line 35: @@
 == Getting Results ==
 Once all of your settings are correct, press the start button to run the machine. When you do this, a graph will appear and start tracing curves.
-[[File:Tresults.JPG]]  [[File:Fresults.JPG]]
+[[File:Tresults.JPG|400px]]  [[File:Fresults.JPG|400px]]

← Older revision		Revision as of 18:03, 26 May 2017
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	== Getting Results ==		== Getting Results ==
		+	Once all of your settings are correct, press the start button to run the machine. When you do this, a graph will appear and start tracing curves.
		+	[[File:Tresults.JPG]] [[File:Fresults.JPG]]

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 a little less than what the datasheet says, just not low enough that it will affect your test. Next is the step voltage for the gate, usually set at either .2 or .5 unless you
 plan on having the FET handle very high voltages in whatever you are using it for (in that case the step could be a little larger). After that is the gate voltage offset which can
-be set at or near 0.
+be set at or near 0. The final three settings are the exact same as they were for the transistor and can be set the same way except that the power max can be higher because FETs

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 Now for the FET, the process is very similar, but some of the settings are a little different. For the FET, the first two options are the max voltage through the drain and
 source and the max current through the source. These, like with the transistor can be found on the devices datasheet. Again, for safety purposes it is smart to put the maximums
-a little less than what the datasheet says, just not low enough that it will affect your test.
+a little less than what the datasheet says, just not low enough that it will affect your test. Next is the step voltage for the gate, usually set at either .2 or .5 unless you

← Older revision		Revision as of 17:29, 26 May 2017
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	on the datasheet, for most smaller transistors use 2 Watts. Once all of these settings are inputted you are ready to test.		on the datasheet, for most smaller transistors use 2 Watts. Once all of these settings are inputted you are ready to test.

−	Now for the FET, the process is very similar, but some of the settings are a little different. For the FET	+	Now for the FET, the process is very similar, but some of the settings are a little different. For the FET, the first two options are the max voltage through the drain and
		+	source and the max current through the source. These, like with the transistor can be found on the devices datasheet. Again, for safety purposes it is smart to put the maximums
		+	a little less than what the datasheet says, just not low enough that it will affect your test.

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 == Getting the Settings Right ==
 Once you have properly inserted the component you are testing, you can turn on the Curve Tracer. Once booted up, the curve tracer will come up with a menu.
-[[File:NPN.JPG|500px]]   [[File:FET.JPG|500px]]
+[[File:NPN.JPG|400px]]   [[File:FET.JPG|400px]]
 The first step on the menu is to tell the machine which type of device you are testing. For a transistor you have to know if it is PNP or NPN, and for a FET you have