Questions tagged [junction]
The junction tag has no summary.
36 questions
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Thermal resistance from junction to case vs junction to ambient
I have been trying to measure junction temperature of some ICs in a PCB board and their IC packaging vary between TO-252, DDPAK and TSOT26 types. For the TO-252, DDPAK packages there is exposed copper ...
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Junction diode "built-in" voltages
When a PN Junction terminal are left open-circuited, the voltage measured between then is zero. The Junction voltage Vo does not appears. Because similar built in voltages arise at metal semiconductor ...
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Why does the resistor need to be placed before the junction in an RTL NOT Circuit
I am trying to implement a simple inverter using transistors. I am confused why placing the resistor between the junction and the LED will not work, but placing the resistor before the junction does ...
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Why is collector current in a diode-connected transistor not subject to the non-ideality of the B-E junction that it must necessarily traverse?
In a recent comment I was asked why a diode-connected transistor behaves as it does.
Jonk's answer here addresses this question, and explains that the geometry of the B-E junction in a signal BJT ...
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Estimating GaN HEMT junction temperature
I think it's quite a simple question, but the solution is not so obvious for me.
I know the equation Tj=Ptot×Rth+Ta, the thermal resistance Rthj-a and RDSon temperature dependance come from the ...
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No voltage gain in a common-emitter class A amplifier using a 3904 NPN transistor - Ngspice simulation
I am currently trying to build an amplifier for a condenser microphone in order to use it as a way to amplify an acoustic guitar. I am having some trouble to achieve my goals.
In order to learn I ...
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What does the 'junction' of a silicon semiconductor look like in real-life?
The P-N junction is a small area within a package where heating is most prominent. Junction temperature is a key parameter we try to track when operating a diode or a transistor.
I am wondering what ...
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Can SiC diodes run at higher temperature than common silicon diodes?
For a usual silicon semiconductor, the junction temperature is rated at 150 degree C. That said, for lifespan reasons, the usual limit for junction temperature is around 100 degree C.
My question is ...
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Why in the output characteristic graph of BJTs, within the saturation region, is the collector current positive?
It is known that in the saturation region of the BJTs the pn junction is reverse biased. The reason for being reversed biased could be explained as follow:
Vce=Vcb+Vbe
Therefore
Vcb=Vce-Vbe
We can see ...
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Why aren't the majority charge carriers attracted by terminals of a battery when the p n junction is reverse biased?
It is clear that when the junction is reverse biased, the free electrons from the n side can not pass the depletion layer and fill the holes in the p side. But why will the free electrons not move ...
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Thermal design propagation calculations for a DCDC converter
So recently I've been doing some design for a DC/DC (this LMR33630) and now I'm doing the thermal design calculations using as a reference this Appnote, also from TI Accurate Thermal Calculations on ...
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Case temperature MOSFET
I am going to use a nMOSFET (NTMFS5C670NL) which will a varied power dissipation. The current going from drain to source is determined by a control signal. The maximum power dissipation for the MOSFET ...
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Majority Charge carriers and electron holes
Suppose I have an extrinsic semiconductor made of silicon and doped with phosphorous. Now, phosphorous has one more electron than silicon. After replacing one silicon atom, and taking its place, the ...
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Schottky barrier at equilibrium
At equilibrium, the barrier for electrons to go from metal to semiconductor is higher than the barrier for electrons to go from semiconductor to metal. Shouldn't that mean there are more electrons ...
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Why is the collector region doped?
As long as within the active region the collector-emitter junction is reverse biased, is there a purpose for which the collector must be doped? Moreover, not only that it is doped, but it is ...
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