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1 vote
1 answer
219 views

Formula for efficiency of half wave rectifier

I came across this formula for rectification efficiency of half wave rectifier: η= (40.6 *resistance of load resistor )/ (resistance of load resistor+ resistance of secondary of transformer + ...
1 vote
2 answers
85 views

Why does light doping imply a large temperature coefficient?

In a discussion about how one can make integrated resistors in a given IC technology, Gray, Hurst, Lewis, and Meyer (Analysis and Design of Analog Integrated Circuits) remark that if we want to use a ...
3 votes
1 answer
221 views

Why do PMOS suffer a worse body effect than NMOS?

Gray, Hurst, Lewis, and Meyer give the following discussion around PMOS transistors which I followed except for the sentence which reads: Good use can be made of this fact in analog circuits to ...
0 votes
1 answer
2k views

What is the difference between cutoff and subthreshold region of an N type MOSFET?

I understand that some current does flow from drain to source when Vgs is below vth and Vds is greater than zero. Why does this have a different name and a different region in Cadence Virtuoso tool ...
2 votes
1 answer
316 views

How are Analog Chips produced?

I am curious about how analog chips are produced. I know that the most advanced logic are made with many rounds of deposition, etching, lithography, etc, but I haven't seen much material about how ...
1 vote
0 answers
87 views

Why do we dope low amount of impurity atoms in a semiconductor?

I read that the doping ratio is usually around 1 impurity/10 million atoms. Why is that ratio so low? Can’t the semiconductor conduct electricity better if there were more charge carriers?
0 votes
1 answer
51 views

Do conduction electrons recombine with positive donor atoms?

Once the 5th valence electron of a donor atom left, it will be to the conduction band, so the donor atom becomes positively charged. My question is if it is possible, that a free electron from the ...
2 votes
1 answer
76 views

Hole current in p-type semiconductors

I know about p-type semiconductors and that there are holes as majority carriers present in the semiconduction. If we apply current through this semiconductor electrons from the valence band will come,...
1 vote
2 answers
86 views

Do holes in a semiconductor just move when there is a current going through the semiconductor?

If a current travels through a semiconductor holes travel to the "end" of a semiconductor, where they can recombine with incoming electrons. Does this also occur if there is no current ...
0 votes
1 answer
135 views

Why is intrinsic carrier density only equal to hole - or electron concentration?

If carriers can be holes or free electrons, why isn´t the intrinsic carrier concentration equal to the sum of the free electron concentration and the hole concentration in the semiconductor?
1 vote
1 answer
77 views

Is generation and recombination same in extrinsic semiconductors?

For example, if we have an n - type semiconductor, so there are more electrons in the conduction band. So wouldn´t the recombination rate increase, opposed to the generation rate, because there are ...
6 votes
3 answers
873 views

Why is the Base-emitter ON voltage as high as 2V in the BJT datasheet?

Below is a snippet from a BJT datasheet. Why is the Base-emitter ON volatge mentioned as 2V? The Base emitter voltage should be 0.7V when the BJT conducts.
0 votes
1 answer
149 views

Is this question wrong? possible to calculate gain without beta or Ic given? [closed]

How to proceed with this question? I can't think from where to start.
0 votes
3 answers
165 views

Dependency of Collector current in common base transistor(active region)

I just started reading about transistors from book "Microelectronics circuits"by Sedra/Smith, This is written in book which I don't understand, any help would be much appreciated For forward ...
0 votes
1 answer
345 views

MOS Capacitor Band Edges

I am trying to understand the MOS-Capacitor band edge shapes. When negative voltage is applied for gate, why does the band edge across the insulator shift upward (and linear decreasing band edge)? ...