Questions tagged [analog]
Analog circuits have a range of voltages, rather than just two as in digital logic.
2,150
questions
-1
votes
1answer
36 views
PLC Audio Transceiver
So the idea of my project is to simply pass through an audio signal which is recorded using a microphone and then transmit it to the power line and on the receiver part the audio will be played by a ...
0
votes
1answer
27 views
Diode Connected MOS
let's consider the equivalent circuit of a diode connected Mosfet.
Since the current source between drain and source is:
gm * Vgs = gm * Vds
and it is proportional to Vds, it means that this ...
0
votes
0answers
17 views
current mismatch PMOS (current mirror)
I am designing a PTAT (proportional-to-absolute-temperature) current generator with 2 PMOS transistors for a bandgap circuit.
In which way does the aspect ratio of a MOS transistor (M1 and M2) ...
0
votes
1answer
18 views
Finding an analog switch IC (BBM & SPDT) for video signal
I'm looking for a SPDT analog switch IC with Break-before-make to switch between video signals. However, the amount of options available leaves me overwhelmed with no clear option in sight.
I've ...
0
votes
2answers
27 views
Op - Amp and Unbalanced Input Differential Signal
Let's consider for instance an Open Loop Op-Amp (for instance with double power supply: VDD and -VDD), which is a good comparator circuit.
The sign of its input differential signal (Va - Vb) ...
0
votes
1answer
32 views
Equivalent circuits in case of equipotential nodes
I have the following basic questions about circuit theory.
1) Consider a generic circuit. Suppose that, because of symmetry or other reasons, we conclude that two nodes A and B of it have the same ...
0
votes
2answers
60 views
analog values to ppm
How to transform a set of analog voltages from V to ppm/K?
I have to use this to calculate the temperature coefficient of a bandgap.
Is the derivative the same as the temperature coefficient ...
0
votes
0answers
34 views
op amp stability theory
A little stuck and could use some help.
This TI stability App Note on page 15 calculates the Thevenin equivalent circuit of a capacitively loaded op-amp and I can't figure out how they get that form ...
1
vote
3answers
105 views
Most simple way to detect small voltage changes(~150mV)
I have one unit of museum cabinet detector that works on 18v. I want make simple security circuit with detector. I've figured out that two output ports on detector are normally contact(NC), but it'll ...
1
vote
1answer
29 views
Charge Injection in Charge Pumps
let's consider the following charge pump, which is used a lot in some PLL circuits (reference):
Let's focus on the left part of the circuit (until the Loop Filter Network): its aim is simply that of ...
0
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1answer
82 views
OpAmp comparator circuit having unexpected behavior
I'm working with the following circuit. It integrates a constant current, and when the output reachs a threshold, another circuit activates the switch, discharging the capacitor. The switch is ...
0
votes
0answers
24 views
Voltage monitoring Circuit
I am trying to build simple voltage monitoring relay.I have ckt that goes to micro-controller pin. can some one suggest me ckt where i can power MC with isolated gnd. i would like to add L78M05 ...
0
votes
0answers
26 views
High voltage pulses amplification
Let's consider this scheme:
With this scheme I wanted to get a pulse of duration 10uS with very high amplitude, starting by the same pulse with 10V amplitude. I need to get a peak of about 400V (...
0
votes
2answers
39 views
Phase Comparator and VCO in PLL
I have a basic question about the simplest PLL scheme:
The purpose of this scheme is that of generating a signal which is a perfect copy of the input signal (which comes for instance from a crystal ...
3
votes
1answer
144 views
How to generate a -5V to +5V sine wave from one DC supply?
I need to generate a -5V to +5V sine wave, the only supply I can use is one battery upto 12v. I need to be able to adjust the frequency with a potentiometer. Output current needs to be a minimum of ...
1
vote
0answers
51 views
Suitable resistance values for an analog IC
I was reading a chapter of the book "Continuous-Time Active Filter Design" about analog filters design. Let's consider the following band - pass filter, in which its inductances may be simulated with ...
0
votes
0answers
30 views
ADC conversion using PIC18
Simple code written for PIC18F24k40 as below. I could able get ADC analog output But when converted to time range selection above 4.15V and below 5 v i used to get display value as negative.
i ...
0
votes
1answer
50 views
Small Signal Voltage Gain - Analog Multiplier Analysis
I'm having trouble with calculating the following:
Small Signal voltage gain from input to output at 400kHz (no LO)
Small Signal voltage gain from LO to output at 400kHz (no signal at input)
The ...
0
votes
1answer
44 views
High voltage non-inverting operational amplifier for DC signal
I am currently using LT6090 with Vcc=140 and Vee=0 for DC signal amplification with gain of 31 in non-inverting mode. For an input signal of 0-4V from a DAC the output measured is 0-124V (step change ...
0
votes
1answer
62 views
Intermediate Op Amp Practice and Material [closed]
I have an interview coming up where I will likely be tested on the basics of ideal op amps. I am confident in my fundamentals, such as solving the typical basic configs (inverting, non inv, summer, ...
0
votes
0answers
26 views
Using an Audio Signal for a Control Voltage for an Analog Synthesizer
I have a Moog Sub 37 Analog Synthesizer and a Korg SV-1 keyboard. Can I take the audio out of either the line outs or headphone out of the Korg and plug it into the volume or filter Control Voltage (...
0
votes
3answers
49 views
What could be the reason to use a current source for potentiometric vane measurement?
On page number 507 of this document, there is a signal conditioner for a potentiometric wind vane.
It seems like they use a current source but I don't get how the mechanism works.
I guess O/P ...
0
votes
1answer
38 views
LVDT Measurement question
Is there any reason one might want to measure both the primary and secondary coils on an LVDT? I assume the primary coil excitation voltage would be constant, but I see circuits around that measure ...
2
votes
1answer
157 views
Amplifying particular range of analog signal
I am working on an a project where I need to get the reading of an analog transducer via Arduino's 10 bit ADC.
The problem is, the range of the signal is such that the 10 bit ADC value is moving from ...
0
votes
2answers
45 views
Role of input resistance in LM384 Audio Power Amplifier
let's consider the LM384 Audio Power Amplifier (here the datasheet)
Can you explain me why is there the 150k resistance? It lowers the device input impedance, which is not good for a voltage ...
2
votes
2answers
67 views
Frequency compensation and feedback capacitance
I was reading the chapter of Microelectronic Circuits (Sedra Smith) about negative feedback systems, and it shows an example of Miller frequency compensation with the capacitance Cf shown in the ...
3
votes
2answers
611 views
How do we create current sources?
Constant current sources (simply, current sources) are useful and necessary devices. They are widely used to drive LEDs, charge capacitors and batteries, to bias differential amplifiers, etc. The only ...
1
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0answers
24 views
Purpose of LLD on GM ratemeter
I'm confused as to the purpose of the LLD (lower level discriminator) setting on a ratemeter GM tube. The LLD establish a threshold hold for the voltage signal from the detector to define an pulse. ...
2
votes
4answers
199 views
+50
Considerations for transmitting the signal from a MEMS microphone over a short cable?
In my application I have the signals from 6 analog MEMS microphones (CUI Devices CMM-3729AT-42108-TR), each amplified by a pair of op-amps in a voltage follower -> inverting amp configuration. The ...
-2
votes
2answers
76 views
Pulsating a vibration module using purely an analogue circuit
I have a simple analogue circuit I'm trying to create. Essentially it's a 1.2V power source that pulsates a vibrator motor - without a 555 timer.
When the circuit is closed, uninterrupted current is ...
0
votes
1answer
30 views
how to determine the small signal parameters of nMOSFET from Datasheet?
as I want to calculate the transfer function of circuit that is meant to generate source current using an Op amp as control loop, I need the gm and r0 of the mosfet(to determine the transfer function ...
-1
votes
1answer
49 views
Does a multidimensional Soft Pot Exist? [closed]
I have no idea if this exists, but I'm looking for a soft pot/ribbon sensor that would function like a laptop trackpad (ie. giving a resistance value for the X position of the finger on the pad and a ...
0
votes
0answers
45 views
How to ground external AC voltage (18V) to Arduino?
I have a project where I need to read 0-18 Volts AC in Arduino's input (0-5V DC).
So I did a circuit with a diode (half wave bridge), voltage divider, and a RC circuit where I tested some values for ...
0
votes
0answers
68 views
How do I get the replacement circuit for this amplifier circuit?
The situation is that we are looking at the circuits for low frequencies.
This is our general amplifier replacement circuit:
And if we look at low frequencies, he presented us with this circuit:
I ...
0
votes
1answer
43 views
What does this circuit with an analog video signal to the emitter and a TX signal to the base of a an NPN do?
The CAM1_AHD is the signal coming from a camera and it goes to the TVI receiver as well as to the emitter of the transistor. The video signaling scheme is analog. The TVI receiver is TP2825 and in the ...
0
votes
0answers
49 views
How do i find poles and zeros from a Bode plot?
I have this Bode plot of CS amplifier but what I need is poles and zeros of the circuit.
I am using Pspice for simulation.
And the Bode plot is:
Now, I calculated the poles theoretically and the ...
0
votes
1answer
36 views
Understanding Plot Showing Impedance, Resistance, and Reactance
I am looking at part of the datasheet for a hydrophone I am using in a project. It includes this figure, which plots resistance, impedance, and reactance vs. frequency:
Part of my project involves ...
0
votes
1answer
67 views
Understanding this analog circuit
The circuit below is from a really old device, however I'm trying to understand it. As far as I can see, the comparator U2 is working as multivibrator or astable oscillator, and this circuit works as ...
0
votes
2answers
55 views
Identify whether PCB 1/4" audio jacks are balanced or unbalanced
I have a Fostex 2016 line mixer and was trying to see in the manual (https://www.fostexinternational.com/docs/tech_support/manuals.shtml) whether the 1/4" inputs and outputs are balanced (TRS) or ...
5
votes
1answer
104 views
Input & output resistance in voltage amplifier design
I'm currenly taking a course in Analog Circuits in the university and we got a task that requires us to design an amplifier, with characteristics that depend on our ID numbers. My amp should be a ...
0
votes
3answers
48 views
Impedance matching in common collector
The last stage of a power amplifier to an 8 ohm speaker is usually a common collector. Now many textbooks mention that it is used as a buffer as it has a low output impedance compared to the speaker (...
0
votes
0answers
17 views
MAX9926 External Threshold
So we have a MAX9926 set to Mode B in a dev rig.
The datasheet doesn't specify the relationship between the EXT input and the Input signal. It should be that we can set what we expect to allow as a ...
0
votes
1answer
81 views
Best way to amplify two analog signals and keep the differential sign
I have an analog sensor with two outputs. Each channel output can range from +0.4 to +0.6V. Currently I am reading them with a 16 bit ADC, and subtracting them after each recording.
It would be ...
0
votes
0answers
32 views
Minimum and Maximum voltages in CRO
I’m generating an AC signal of frequency 1kHz, amplitude-870mV, offset voltage- 440 mV and given to oscilloscope (Division_1V.)
In the oscilloscope, the maximum voltage is 1.84 (it is fluctuating ...
-3
votes
0answers
57 views
Analog wavelet generation grey beards only
I would like to generate some very complex signals entirely in analog, this system will be used to deliver an important result in quantum mechanics. Ultimately I will build a reconfigurable analog ...
1
vote
1answer
57 views
What would it take to add Bluetooth capability to a digital (musical) keyboard?
I am completely new to electrical engineering. I have a software background and have an interest in tinkering with hardware.
I'm wondering what knowledge/engineering skill/equipment is required to ...
0
votes
1answer
43 views
ac/dc coupling and DC offset to read DC voltage in analog oscilloscope
A function generator is connected to an analog oscilloscope. I can see a sine wave. Can I read DC voltage with the help of DC offset knob? If so, can the minimum DC voltage be negative?
0
votes
1answer
34 views
How to use analog mode GPIO pin(not ADC input channel) for ADC?
I want to use a GPIO pin which is configured to be "Analog Mode" for ADC.
I am working on STM32L073 series microcontroller. The pins with ADC input channels
are used already. So I need to choose ...
0
votes
1answer
122 views
How to measure amplifier circuit loop gain
In the last few days I've tried to understand how to get the loop gain (Aol*ß) of my amplifier circuit.
I've received several suggestion.
I would like to hear your opinion on this matter.
Are these 2 ...
0
votes
3answers
72 views
Virtual ground in positive feedback op amp
In negative feedback Op amp Virtual ground condition is satisfied but in positive feedback it doesn’t why?
