# All Questions

18 questions
58 views

### differential amplifier gain

i know that the differential gain of the differential amplifier ( mosfet or bjt ) is _gmRc or _gm Rd looking at the curve : if the current went down in one side and up in one side the gm will change ...
50 views

### input resistance of differential amplifier

i have a question about the differential amplifier i know that the input resistance for the common mode is Rin = rpi + 2 Beta Ree / 2 but my question is what is the input resistance for the ...
50 views

### Gilbert Cell Output Current

I do not understand the basic of a Gilbert cell. I see that as its output we consider the output differential current Io. But I do not understand it. Is the load connected between the points 1 an 2? ...
47 views

### HFA3096 transistor array breakdown voltage

In the book Learning the Art of Electronics, one of the labs is to build a differential amplifier with a CA3096 transistor array. The author admits that the chip may be difficult to find and gives the ...
54 views

### Differential Amplifier Exam Problem

I am lost with how to approach part C and D of the question. In fact, I need some intuition with how to tune a differential amplifier.
66 views

### Finding Drain voltage of current mirror

Below I have a current mirror loaded differential amplifier. Can somebody please Just give me an idea of how to find the drain voltage, vd8. I am stuck because I don't see the relationships that can ...
67 views

### Finding a range for a common mode signal

I have the question below Here is the figure they are talking about: (Text and images from: "Microelectronic Circuits" book by Sedra/Smith, 7th edition, chapter 9) Here are the answers to the ...
387 views

### How to apply 180 degrees out of phase signal at inputs of differential amplifier in laboratory when only one function generator is provided in lab?

In this differential operation experiment, two input AC signals have to be applied to the bases such that they are 180 degrees out of phase with each other, but I am not sure how to invert an AC ...
643 views

### Differential gain of amplifier with current mirror and NO LOAD

Please consider the differential amplifier (Q1&Q2) with current mirror active load (Q3&Q4) as shown below: simulate this circuit – Schematic created using CircuitLab I know many ...
250 views

### Choosing proper CCS current for discrete transistor amplifier's differential and VAS stages

Here is a figure from "Audio Power Amplifier Design" by Douglas Self. Self using almost same current values (4mA and 6-8mA) in many examples without explanation. How to choose these values properly ...
2k views

### Purpose of voltage amplifier (VAS) in three stage amplifier design

Can someone explain me benefits of this design (found in Douglas Self's book) in comparison with "classic" npn-based long-tailed pair? What second stage actually does?
1k views

### How to calculate the transconductance of this circuit?

I have this circuit where the "FES" blocks are simple current mirrors and the block "PD" is a differential pair. All the transistors in those blocks are BJT, NPN or PNP, respectively. I found all ...
335 views

### Saturation in differential pair

I'm reading Analysis and Design of Analog Integrated Circuits by Gray & Meyer. In the differential pairs' chapter, there is this circuit and it says: Assume the collector resistors are small ...
1k views

### How does this BJT transistor circuit works?

I just wanted to know a little more about this circuit about how it works a more in depth analysis I mean. I know there's some kind of differential amplifier and a Zener diode for voltage regulation ...
163 views

### differential amplifier will cancel DC present at input

In differential amplifier, it is written that "only AC signal will be amplified and DC part at the input will be canceled and hence there is no need of DC blocking capacitor". I am not getting this ...
397 views

### Modeling diode connected transistor in differential amplifier

I have question about the analysis of common-mode gain of BTJ differential amplifier with active load on the Sedra Smith book. In this book, the differential-mode gain $Ad$ is derived based on the ...
I am trying to solve this assignment Consider this schematic (the BJT's are in the effective area, with $\beta=200$ so as to $i_e\approx i_c$). Also $R_1>>R_E+r_e$. Define the ...