Questions tagged [solid-state-devices]
Refers to solid devices built on silicon wafers or ceramic substrate. Materials used could be silicon, germanium or gallium arsenide with copper conductors and oxide based insulators. Doping is the addition of performance enhancements compounds such as gold or germanium. Includes transistors of all types and logic, analog and special purpose devices such as CCD sensors. When done devices are sealed with plastic or ceramic compounds.
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Do MOSFETs Share Avalanche Energy?
I understand that MOSFETs act like resistors when they are on, and that is why they share current nicely. (As opposed to diodes and BJT's, which act like voltage sources when they are on, and that is ...
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Generating cold plasma using a Piezo Transformer
I am trying to generate cold plasma using a multi layer piezo transformer.
My understanding was that it was as simple as applying a 15 Vpp to the transformer, but it did not work.
I was trying to ...
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Will Any SCR Trigger Optically If It Is Exposed To Light?
I read somewhere that all SCR's are photosensitive, in the same way that all diodes emit light, but some are optimized to take advantage of this property while others are not.
There is an SCR I want ...
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MOSFET SOA: Why is the max current limit lower for DC case? [duplicate]
Shown above is the academic definition of MOSFET SOA. Rdson limit is not considered as a real limit in most academic texts - that's ok- understandable.
But why is the max drain current limit different ...
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Is It Possible To Choose a Higher Holding Current When Designing SCR?
I'm looking at this data sheet: SCR data sheet on Digikey
This device seems perfect for what I want to do, with 1 exception:
The holding current is way too low.
Various forums have suggested that (on ...
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Simulating an equivalent circuit model of a laser in LTspice, how does it solve this circuit?
I want to know how LTspice solves this circuit as there are node voltage (vj) dependent current sources (Ist and Isp) present in this circuit. Also, I had an unknown parameter, Ne, whose value I ...
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What percentage of a DRAM cell size is occupied by the transistor and/or the capacitor?
Assuming that we have a 1T1C DRAM cell manufactured at 22nm process. Based on this we can have an idea about the cell area (0.026 um^2 in this case). However, I could not find specific information ...
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For sufficiently low duty cycle, can you get away with driving SCR above rated current as long as A^2 * s are maintained?
I'm wondering if the A^2-s rating of an SCR is what ultimately decides whether a given current for a given time is okay, even if the data sheet does not list such a number.
For instance, right now I ...
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What types of power rail are there in an integrated circuit?
I understand that power rails provide the energy required for a circuit to function. Intuition tells me there must be at least two types of rail, one providing power and another taking it away.
But I ...
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What is equilibrium carrier concentration in a semiconductor? Is it material specific? How to calculate it?
Is equilibrium carrier concentration dependent on doping density? If it is, then how to know how much the doping density should be for a particular semiconductor device?
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Switching low voltage with high accuracy
To do some discharge tests, I want to connect 1.5 V batteries to very low resistances for a short amount (10 - 200 ms) of time, then have them disconnected for at least a couple of seconds.
What would ...
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RF power amplifier tuning of output stage tube vs transistor
In the old days with vacuum tubes for power amplifiers we carefully tuned the output stage, dipped the plate current to get maximum efficiency.
Looking at todays transistor PA circuits I don't see a ...
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Simulated speaker dummy load for solid state
This is specific for 6 string electric guitar amplifiers. The convention appears to be use a resistor equal to the nominal DCR of the intended speaker load, usually 4 or 8 Ω.
What I have found out was,...
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Does the gate leakage current increase or decrease the drain current in MOSFET?
I know that the gate leakage means that the electrons are injected from the gate metal into the channel, therefore the conventional current direction is from channel to the gate. From KCL, I think ...
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How to draw power from one of two sources according to priority, with indication for used source?
If two 5V power sources exist, one being always on and the other not (such as an ATX powersupply's standby 5V and "on" 5V rails), how could I draw power only from the "on" rail ...
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What is exactly a "stabistor"? How does it work and how is it constructed?
Today, for the first time in my life I encountered the term "stabistor". From a quick search on the Internet it seems it's a two-terminal diode-like semiconductor device used to regulate low ...
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Why do SSDs have a limited lifespan?
Why do solid-state drives even have a limited number of read/write cycles, usually 100,000-300,000 cycles?
For hard-disk drives, it is understandable why they wear out. That is because they have ...
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Semiconductors: electrons more mobile than holes despite being heavier?
I apologize if this is a very basic question. But I have always known it to be true that in Silicon, electrons have higher mobility than holes. From my semiconductor physics classes in first year, the ...
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How do I (can I) replace the relay in this circuit with a transistor?
Background
I have the following circuit and it has been working for years.
Please note that the circuit drawing may not match the real circuit exactly, but it is just a diagram to attempt to get my ...
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What prevents MOSFET drain-to-gate leakage current?
What in the structure of a MOSFET prevents leakage current flowing from the drain to the gate of a MOSFET when the drain is at a higher potential than the gate? I am assuming that drain-to-gate ...
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Potential distribution in MOSFET
Let us assume that an NMOSFET has its source, drain and substrate grounded therefore VDS and VSB=0 V . We apply a gate voltage VGS=2 V and I want to know how this potential is distributed as we move ...
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Trouble with body effect physics
I’m struggling to understand why a negative voltage applied to the bulk contact of an n-type MOSFET increases the threshold voltage.
I read other similar questions and I get that the negative voltage ...
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Calculating capacitance in a MOS capacitor
A \$MOS\$ capacitor with \$t_{ox}=10nm\$ has an \$n^{+}\$ polysilicon gate electrode and an \$n\$-type substrate with doping concentration \$ N_D=10^{15}/cm^3\$ . Given: \$V_T=kT/q=26mV\$, \$\...
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Is it possible for an SoC to have a built-in SSD?
Is it possible to have an SoC that includes an SSD on-chip, or are there technical constraints that prevent that? What are those technical constraints, if any?
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MOS Capacitor band diagram question
In a MOS system, is the energy offset between metal/oxide or semiconductor/oxide always the same regardless of the gate voltage applied? In other words, are A and B in the diagram above always the ...
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Energy band diagram of a polar material
For a single piece of a polar material (ex. GaN, AlN, etc), there exists a constant electric field inside the material due to the bound charges at the surface.
Above figure shows the resulting band ...
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How to power this RF microwave solid state switch
I have the following RF switch:
After googling for several hours, I have found that it is a solid state switch,
from DC to 26.5GHz.
I've also been able to test that between the golden plated female ...
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Why does the majority carrier concentration near the junction not decrease under forward bias? (PN junction)
We see that the current due to the majority carrier decreases near the junction as shown above, which means the majority carrier concentration should also decrease since the diffusion current is given ...
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Why are quasi-Fermi levels flat across the depletion region in a pn diode under forward bias?
Why is the quasi-Fermi level flat across the depletion region in a pn diode under forward bias?
I get that EFn decreases on the p-type side and EFp decreases on the n-type side due to recombination, ...
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Secondary Coil Malfunction in an SSTC Circuit
I’ve designed an SSTC circuit which is based on a different topology and I wanted to accomplish it in real life. The circuit is operating at approximately 1.5 MHz during resonance and inherently, the ...
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Derivation of microscopic Ohm's law from macroscopic version?
What I tried was:
$$\overrightarrow{E}= - \triangledown V \qquad \qquad\qquad\qquad (1) $$
$$V= IR\qquad \qquad\qquad\qquad\text{(Ohm's law for materials where V}\propto \text{I)}$$
$$\text{...
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Given a energy band diagram, can you always calculate potential, electric field, and charge distribution?
Given a band diagram, where do you start to get the electric field and charge distribution?
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Electric field of Schottky diode
Reference: Device Electronics for Integrated Circuits 3rd Ed. Richard Muller
I am trying to understand how to calculate the maximum electric field. The answer given in the book is $$E_{max} = \frac{-q ...
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Why does the value of shunt resistor need to be very high for solar cell's greater efficiency?
In the circuit equivalent of a solar cell, shunt resistor is described as "The irregular polycrystalline lattice grain boundaries that resist to the flow of electrical current in the silicon ...
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Solid state relay
How to connect a solid-state relay to an output MOSFET, which has 2 drain pins without the ground which I am refering to the image in the attachment?
https://www.mouser.de/ProductDetail/Toshiba/...
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Why does channel length modulation only occur in the saturation region?
As drain voltage is increased, the reverse bias across the drain-body junction also increases and thus the width of the junction should also increase which should deplete the channel length as well. ...
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Is saturation region defined for a "given" collector emitter voltage?
I have seen the traditonal saturation regions graphs (attached). The graph gives the impression that there is a huge region which is saturation region. Shouln't the saturation region be for a "...
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Does the collector voltage have to be greater than the emitter voltage by few tenths of a volt for an NPN transitor
For an NPN transistor, does the collector voltage have to be greater than the emitter voltage by few tenths of a volt for it to be in active state? If yes what is the reason?
Also it says greater by a ...
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How does the stored charge gets decayed when going from forward bias to zero bias?
In a pn junction diode when forward biased, excess electrons and holes get stored in p and n regions respectively.
If we short the diode by connecting p,n terminals with a wire,
how do these stored ...
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Relation between forward bias and current in a diode
I have seen the VI graph to depict the relationship between forward bias and current. (left graph) and I think I get it. I have also seen another graph (right graph) to depict the relation between ...
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How can a Zener diode maintain a constant voltage?
A Zener diode in reverse bias more than breakdown starts conducting. If you increase the reverse bias:
It conducts more i.e current in it increases
The voltage across it remains same
I think I get ...
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What is the exact meaning of 0.7V voltage drop in a forward-biased diode?
this question is partially (but not totally) discussed here:
Why do diodes have a voltage drop?
Does the power drop on a diode become entirely heat?
The conclusion is that, in a forward-biased diode ...
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How to convert spontaneous emission into stimulated?
I have a semiconductor diode that has spontaneous emission (LED).
The question is what can I change in the fabrication of the diode to improve its performance such that the diode gains a stimulated ...
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Trying to Identify Static or Thermal Transfer Tape
I came accross this solidstate drive which is in a custom plasic and metal enclosure.
There is a sheet of material cut out between the metal top and the drive. I'm trying to figure out what it is, it'...
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MOSFET current at very low temperature (4K)
I am trying to model the current at low T. To do so I need to compute the integral between the fermid diract statistic and the conductivity, with respect to energy. My problem is that I cannot ...
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Replacing X-ray or any radiation generating vacuum tubes with solid-state alternatives? [duplicate]
What are the reasons X-ray vacuum tubes could not be replaced by solid state alternatives?
I'm thinking if it is possible to make a compact solid-state X-ray or higher energy photons generator just ...
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Why most particle accelerators used vacuum diodes instead of transistors?
HERMES III (High Energy Radiaton Megavolt Electron Source) at the Sandia at Sandia National Laboratories is the world's most powerful gamma ray generator. HERMES-III produces a highly energetic beam ...
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Amplifiers without vacuum tubes or transistors?
Are there amplifiers that can work without vacuum tubes or transistors? Is it possible to create a working amp with high power without vacuum tubes or transistors?
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Purely Solid-State Circuit Withstanding 1kV, able to source 125mA
I'm looking to design a purely solid-state circuit that can perform the following:
Handle an AC Source with Vpk=1kV and act like an open circuit. (Schematic 1)
When the source is removed and replaced ...
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What is the structure of GaAs?
Ga has three valence electron, and As has five valence electron. How do they share electrons so that each has 8 valence electrons? Does each Ga atom share 5 electrons with 5 different As atoms?
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