T
treez
Guest
Hello,
I am making a 100KHz sinusoidal test current.
It is +/500mA peak to peak.
Is the following circuit ok?……..it simulates ok……but is it OK?
Schematic:
https://i46.tinypic.com/13z4ojs.jpg
The 0R39 resistor is the resistor on the test PCB into which I will connect the sinusoidal current....(as you see it connected here)
In the simualtor the current never goes much above 500mA, which is handy….lets hope it doesn’t go much above +/-500mA in the real circuit?
Also, the PNP dissipates 1.2W, so will need to be a power BJT……can power BJT’s switch at 100KHz?
TO220 BJT
https://www.fairchildsemi.com/ds/TI/TIP31C.pdf
...this TIP31 has a lousy gain of 10.....are there better ones out there?
(In the actual circuit, the 0R39 resistor has +/500mA sine flowing in it, and the subsequent voltage across the resistor is then amplified by an opamp, and i really want to check out if this opamp amplifies it properly.....so hence my needing this test source.)
I am making a 100KHz sinusoidal test current.
It is +/500mA peak to peak.
Is the following circuit ok?……..it simulates ok……but is it OK?
Schematic:
https://i46.tinypic.com/13z4ojs.jpg
The 0R39 resistor is the resistor on the test PCB into which I will connect the sinusoidal current....(as you see it connected here)
In the simualtor the current never goes much above 500mA, which is handy….lets hope it doesn’t go much above +/-500mA in the real circuit?
Also, the PNP dissipates 1.2W, so will need to be a power BJT……can power BJT’s switch at 100KHz?
TO220 BJT
https://www.fairchildsemi.com/ds/TI/TIP31C.pdf
...this TIP31 has a lousy gain of 10.....are there better ones out there?
(In the actual circuit, the 0R39 resistor has +/500mA sine flowing in it, and the subsequent voltage across the resistor is then amplified by an opamp, and i really want to check out if this opamp amplifies it properly.....so hence my needing this test source.)
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