3
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Level Shifter design. 0-10vdc to 0-24vdc using pnp transistor
The solution is a circuit similar to the one posted by Jens, but delete one resistor and add one 18 V zener diode. This prevents the transistor from conducting when the input is high.
When the input ...
- 18.2k
2
votes
Accepted
Diode and bipolar NPN transistors orientation not correct, says JLCPCB
I guess what causes the populated view to show up inverted, is that the pick and place file generated from KiCad ends up 180° rotated for polarized components *. Therefore, they fix this to adjust the ...
- 19.6k
2
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Accepted
NPN Transistor Base Current Calculation from Beta, Vth, and Rth
I'll write up something for you -- a problem and a solution. I'll make it tricky, but real. In fact, I just posted up this schematic a day or two ago. So it is fresh in mind. It may look like it ...
- 5,662
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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 ...
- 19.6k
2
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Level Shifter design. 0-10vdc to 0-24vdc using pnp transistor
Since you've added that you can use NPN transistors, this is a reliable way to do what you request. If you can invert the input by some other means you can eliminate Q1 and R1 (connect R4 to Q2 base).
...
- 384k
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Reducing the fall-time of a P-channel MOSFET
Here is a modified circuit:
I didn't use the exact MOSFET model. The one you are using has a lot of gate charge. Also note the absolute maximum Vgs is 20V, but that's typical of such parts.
Here is ...
- 384k
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Level Shifter design. 0-10vdc to 0-24vdc using pnp transistor
With these resistor values the output voltage changes at an input voltage of around 8 V.
If SW1 is open or V1 is at 0 V the base current of Q1 is high enough to provide close to 24 V at the PLC input (...
- 6,162
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Transistor works with just base connected
simulate this circuit – Schematic created using CircuitLab
Figure 1.
(a) A transistor when tested with a diode tester appears to be a pair of PN (diode) junctions.
(b) In this case Q2 is being ...
- 171k
1
vote
Accepted
Transistor works with just base connected
Yes, it's normal, current into base flows out from emitter, regardless of what connections, if any, you have on the collector.
The base current controls the collector current. Both base and collector ...
- 137k
1
vote
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.
- 2,555
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Low Drain-Source MOSFET Leakage
After stumbling upon this thread I thought it's time for an update.
Looking up the various part numbers mentioned here I began assembling a list of candidates for my own project. I needed ...
- 25
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