Thanks Salas and Andrew for your comments and instructions.
Did some tests on a sample of 28 transistors.
I used a 9V battery with 100R in series to Drain, with G and S shorted to battery negative.
Measured also resistance from D to S and found always values in the region of thirties ohms.
The values were read with my DMM on both resistor terminals as bellow:
- 0,840V. - 0,984V. - 0,647V. - 0,938V
- 0,770V. - 0,944V. - 0,830V. - 0,804V
- 0,730V. - 0,638V. - 0,900V. - 0,965V
- 0,684V. - 0,957V. - 0,655V. - 0,925V
- 0,720V. - 0,884V. - 0,720V. - 1,014V
... And so on.
What do you think? If I use I=V/R, in one of the values, say 0,840V divided by 100R, I get 0,00840A. Is this correct?
I believe that the higher values are the most suitable, correct?
Thanks once more, I will try to show you my wok as this goes on.
Did some tests on a sample of 28 transistors.
I used a 9V battery with 100R in series to Drain, with G and S shorted to battery negative.
Measured also resistance from D to S and found always values in the region of thirties ohms.
The values were read with my DMM on both resistor terminals as bellow:
- 0,840V. - 0,984V. - 0,647V. - 0,938V
- 0,770V. - 0,944V. - 0,830V. - 0,804V
- 0,730V. - 0,638V. - 0,900V. - 0,965V
- 0,684V. - 0,957V. - 0,655V. - 0,925V
- 0,720V. - 0,884V. - 0,720V. - 1,014V
... And so on.
What do you think? If I use I=V/R, in one of the values, say 0,840V divided by 100R, I get 0,00840A. Is this correct?
I believe that the higher values are the most suitable, correct?
Thanks once more, I will try to show you my wok as this goes on.
How well did your battery hold it's "starting" voltage till the completion of the 28 measurements?
If it started @ 9.0V and held at >8.9V till the end then Vds was in the range ~8.3Vds to 7.8Vds. Good enough for rough batching to 2 sig fig.
However if the battery voltage fell to ~8V, then the Vds range changes to ~8.3Vds to 6.8Vds. This range of Vds being very significantly different from the 10Vds specified for Idss will increase the "errors" in your results and between your results.
A quick scan of your 20 posted results shows Idss between 6.3mA and 10.1mA
If it started @ 9.0V and held at >8.9V till the end then Vds was in the range ~8.3Vds to 7.8Vds. Good enough for rough batching to 2 sig fig.
However if the battery voltage fell to ~8V, then the Vds range changes to ~8.3Vds to 6.8Vds. This range of Vds being very significantly different from the 10Vds specified for Idss will increase the "errors" in your results and between your results.
A quick scan of your 20 posted results shows Idss between 6.3mA and 10.1mA
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