Nov 22, 2018 · I have been solving BJT circuits on my textbook and stumbled upon a PNP BJT small signal model question. It asks to build the small signal model of a PNP transistor circuit. When I checked the proposed solution, I was a bit confused. Following are the original circuit and the proposed small-signal model.

Jul 6, 2021 · The PNP transistor at the right side doesn't follow any characteristics of the 4 modes of operation of BJT. How is this possible? PSPICE simulation has shown quite similar results. Here, beta=100.

There is a temptation to think that we could do the same trick with an PNP transistor as shown in Figure 1b. The problem is that the emitter-base junction is always forward biased. This will apply the 12 V to the chip output and destroy it or, if there are protection diodes on the output, the current will flow through the protection diodes into ...

Here is an answer which is more rough, but easy to recall and useful as a first approximation. Only the case of a NPN bipolar junction transistor is dealt here; things are similar for PNP bipolar junction transistors.

Apr 13, 2017 · The only difference lies within the functionality of the transistors. In grounded (common) emitter configuration, when a base current is provided (or to be more practical-when base is connected to 5v supply) of a PNP transistor, no conduction takes place as the majority carriers in n region are electrons whose motion is suppressed and no path is formed b/w …

Mar 16, 2023 · Just wanted to say that if the base voltage of a small signal PNP BJT is sufficiently reverse-biased, it will break down. For common PNPs this may be at about 5, 6, or 7 volts, roughly. If you need some kind of fuller answer and explain better, I might try an answer. Otherwise, that's all you need to know I guess. \$\endgroup\$ –

Then I have a question, is it possible to have a command of 3.3V and the PNP tied to the 5V. I am thinking it is not possible because if the command is at 0 the BJT is saturated and everything is OK but if the command is at 3.3V then Veb= 5-3.3=1.7>0.7 and the …

Jun 18, 2016 · When operating in saturated mode, the power consumption of the BJT can be substantially lower than when in active mode. This leads to less self-heating of the BJT, and probably a longer operating life. Note my use of "may" and "can". This all depends on the resistor values being chosen appropriately for the application.

Feb 19, 2016 · Considering the identical layout, and NatSemi being the source of the layouts, the shorted Q2 PNP C-E will act the same. As @Robherc suggests, it's likely used as a matched pair, to provided some performance gain compared to a random diode which would have a much different performance.

Feb 27, 2019 · PNP BJT small signal model. 0. BJT Circuit Current. 0. Polarities of high current bypass, and short ...