4
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BJT ring oscillator
Just to point out the use of a Schmitt (one that in this case uses 3 BJTs, too, but it is only one Schmitt stage), here's an example that I literally threw together from memory and some guessing from ...
- 5,547
4
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BJT ring oscillator
When is an inverter NOT an inverter? (Pun intended.)
Understand that digital is a subset of analog. Digital logic is a collection of rules, which, when a system obeys them, can be used to synthesize ...
- 27k
3
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I don't understand this temperature controller circuit's behaviour
This is a fundamental issue.
You need to prevent the output from going so close to ground that the difference between the inputs becomes less than the offset voltage of the op-amp, if it's driving the ...
- 383k
2
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Accepted
What sort of transistor is this?
It can't be really old since ST isn't that old. Mid to late 1980s at the earliest. You can look up when SGS and Thomson got together. Perhaps 1988 is the year of manufacture.
So probably silicon (you ...
- 383k
2
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Accepted
How do I select and use a BJT in a simple LED circuit?
Transistors don't have minimum voltage requirements per se, the limiting factor is generally the base emitter voltage \$V_{BE}\$ which is around 0.6 V for a silicon transistor.
For saturation, you'll ...
- 19.5k
1
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Accepted
The condition of linear operation of the transistor Dipole in small signal mode
For a BJT, the voltage scale is the thermal voltage, about 26 mV at room temperature. The base voltage change must be substantially smaller than that to approach linearity.
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BJT Amplifier simulated gain is only around 80% of calculated gain. Why is this and how to improve calculation vs simulation accuracy?
When you try and make a single stage BJT have a gain that is realistically pushing the limits, you have to factor in the miller capacitance feedback effect due to collector-base capacitance. It may ...
- 443k
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How does this BJT monostable one-shot work?
In the quiescent state, assume Q1 is OFF and Q2 is ON.
I would have been a little more descriptive. Assuming Q1's base doesn't draw much, it's base sits at \$1\:\text{V}\$ due to the divider.
Assume \...
- 5,547
1
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BJT ring oscillator
If you want a square wave and you need an inverted output, use a hex(6) Schmitt inverter IC with resistor from input to output and a capacitor from input to ground..
- 11
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