Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [circuit-design]

a term to describe how a circuit should behaved based on accomplishing a particular task. When designing circuits, one should consider how it works, the target specifications, efficiency, cost effective, code compliant, and ethics.

1
vote
1answer
55 views

Zero crossing detection circuit correct?

I am working on a DIY AC dimmer circuit with arduino. This project is part of the AC dimmer circuit as mentioned here Since, I was stuck in so thought of retracing my steps and checking each part of ...
0
votes
1answer
54 views

Is there a relay that disconnects BOTH positive and ground wires?

My latest time-lapse camera rig, was failing to run due to the constant ground connection on the camera power input. This is an off-grid, solar-powered rig, combining a Raspberry Pi and an Arduino, ...
0
votes
0answers
34 views

How to play a singular, clear, WAV file that can be started at a push of a button?

Im new to circuits and I recently came across a problem in my adventures. I want to be able to play a WAV file of my choice at the push of a button. There is only one file that I would like to be ...
0
votes
0answers
19 views

Multiplication with full adders

I have a homework on digital circuits. Basically, I have to multiply two binary numbers using only AND gates and 1-bit Full Adders. I have made quite a bit, but I can't figure out how to handle S3. ...
0
votes
0answers
27 views

Choosing the right amplification/gain for the internal PGA of an ADC IC

Problem I need to read a sensor (multiple of the same kind) with a microcontroller. The sensor I have, outputs a signal in the range of 0mV up to 20mV. Thus, it needs to be amplified and send to an ...
3
votes
3answers
620 views

Building circuit to amplify small sensor signals using an Instrumentation Amplifier and 24-Bit ADC

I'm a beginner when it comes to circuit design and I have spent the last few weeks doing research on this topic. I have now chosen some ICs (Instrumentation Amplifier and ADC) and would like to build ...
0
votes
0answers
29 views

How to get two outputs of 5 and 12 V from bench power supply using DC to DC converter

So i want to design 3 circuits which are similar in structure. Input of the first one is anywhere between 0-5V and i need 2 outputs 5v and 12v Input of the second one is anywhere between 5-12v and i ...
3
votes
1answer
63 views

Designing 4th order Butterworth Multiple feedback bandpass filter

I'm trying to design a 4th order Butterworth bandpass filter using Multiple feedback topology. The design requirements I am trying to achieve for this filter are; Q factor = 10, Av = 11, fc = 100kHz ,...
4
votes
4answers
1k views

Voltage across LED and source when LED is floating from one end

Refer to these pictures and can you explain why is there 3.335V coming across LED and the LED isn't even turning on. Also to note is that changing the resistor value does not change voltage at D2(A2) ...
0
votes
1answer
41 views

Question about SR latch timing

I have a question about how SR latches work: To my understanding the real-world implication is that one of the two gates will receive power first and produce an output signal, and they aren't going ...
-2
votes
0answers
53 views

At the high level of abstraction, does the choice between ASIC, FPGA or microcontroller matters?

I am new at hardware design, and my goal is to be able to implement a circuit. To start, I don't go farther than the 2nd level of abstraction, but I am supposed to write both the behavioural and ...
1
vote
1answer
32 views

How does the transistor topology look like for a gate of this logic inverter?

How does a single inverter gate of this hex inverter, look like in transistor level? I don't mean the actual photo, but how does the transistor topology look like? Does the BJT inverter (see below),...
1
vote
0answers
25 views

Electronics interface circuit for PIN Photodiode

I am designing an interfacing circuit for PIN photodiode which will be used in NIR spectrophotometer project. The PIN diode is <...
0
votes
1answer
51 views

What does it mean if my voltage regulator is acting as a wire?

When i connect 24V to my input pin, and connect ground pin to my Ground, it gives a short circuit at the bench power supply. What does this mean? Did i kill my voltage regulator?
0
votes
0answers
44 views

Using circuit breaker instead of a fuse

I am making a contraption that uses an atmega328 to trigger a water pump to water the garden plants on a schedule. The controller will run on low power mode to sleep all day and wake up to water the ...
1
vote
2answers
33 views

Addition and subtraction of binary digits

I have to solve the following exercise : Extend the circuit of the first part (the first part was an adder of integer numbers of 2 binary digits) in order to execute addition and subtraction of ...
1
vote
1answer
33 views

Implementing circuit with d-flipflop in verilog

I'm fairly new to Verilog and I'm currently trying to do a structural implementation of a circuit that consists of an d flipflop, it has inputs x and y, x and y are exclusive or'd and that result is ...
7
votes
2answers
1k views

Will these two transistors (BC558A and BC558B) function in the same way?

I'm currently following this guide on making an Arduino OpenTherm Controller. After finding almost all of the parts without any issue; my only question remained with the "PNP transistor" named in the ...
0
votes
0answers
32 views

I2C line pulled low by MCP23017

A simple interface of MCP23017 with Rpi using I2C lines. Since there is already an internal pull-up resistor of 1.8k on rpi I didn't use any pull-ups n I2C lines. Running ...
0
votes
2answers
56 views

Scenarios where Inductor back EMF would result in damage of circuit or component

Let's say that there is a simple circuit with the following components (ignore values): LEFT: a simple power supply (assume DC) TOP: load (resistor) and inductor RIGHT: switch BOTTOM: load (resistor) ...
1
vote
1answer
41 views

Make a circuit that indicates an odd number of ones using a 3-8 Demux and two logic gates

Using 3-8 Demux and two logic gates, make a circuit that received 4 bits and returns 1 if the number of 1's is odd and else returns 0. My try: Using truth table, we get that the desired function is: ...
-1
votes
0answers
34 views

How do I find i5 in this circuit?

I've tried using KCL and KVL but I've never analysed a circuit with a current source please helpM.
1
vote
1answer
26 views

Reducing the amount of controller output required - making k of n binary to unary decoder out of 1-of-n decoders

I am a kind of self-taught electronics dabbler and being a selftaught tinkerer has the unfortunate consequence of reinventing the metaphorical wheel quite often. I'd like to avoid this fate again if ...
-3
votes
3answers
85 views

How to control two separate circuits with one switch? [duplicate]

I have two separate circuits with different types of diodes. One circuit draws 3,5V and the other draws 9V. How can I wire this up so that one switch can turn both circuits on or off? As far as I ...
2
votes
1answer
72 views

What's the purpose of this circuit section?

I'm experimenting on VCA circuits and found the same (or similar) pattern in many linear VCA projects found in internet using LM13700 OTA. The specific section I'm curious is made by an Op-amp, a ...
0
votes
1answer
52 views

How to calculate maximum amount of bulbs I can connect in parallel to match design specification of 1.5 A?

I'm designing a sensor triggered circuit that involves 220 V passing on a PCB, so I designed the board thickness to withstand a maximum of 1.5 A. The main load on the circuit would be a series of LED ...
0
votes
1answer
56 views

A simple circuit to turn on door LED when someone visit me

I want a simple circuit do an alarm light that tell me someone visited me. When someone visits me and in the case no one answer the door, I want to know that. So I want a press button switch outside ...
0
votes
1answer
69 views

Ultrasonic Sensor Serial Output Grounding Issue

I have a small circuit which uses a Maxbotix Ultrasonic sensor (Datasheet: https://www.maxbotix.com/documents/HRLV-MaxSonar-EZ_Datasheet.pdf) to take distance measurements and then transmit them over ...
2
votes
0answers
28 views

How to connect the Peltier module to TEC W1209?

I am trying to control my Peltier module using the W1209 TEC. I set the P0 to H, so that it should provide voltage to my Peltier module until the temperature reaches the set temp. The LED turns on ...
2
votes
2answers
85 views

How series resistors influence clearance-creepage requirements?

simulate this circuit – Schematic created using CircuitLab I'm designing a circuit which should leak some amount of current from AC line to PE. The question is regarding clearance-creepage ...
0
votes
0answers
30 views

Choosing a suitable FET for a design project

I'm currently working on a project to produce a high speed and high voltage pulse. I'm trying to find a suitable FET. I intended to supply a voltage of about 50v to circuit. And using the FET to go ...
0
votes
0answers
25 views

How do I draw a gate diagram using minimal number of NOR gates for a 7 segment display that outputs CHOP?

My teacher has given us the chance to pull up our grade with this take home question. However he did not cover this in class and I cannot find any good material to solve. Any help would be appreciated!...
2
votes
2answers
57 views

Understanding inductor and LED ripple current in LM3409

I am reading the datasheet of the LM3409, specifically section 9 "Application and implementation". My intent is to understand how to calculate the values of the components needed for my specific ...
1
vote
1answer
43 views

Voltage Divider with low noise?

I'm working with a nano scale motion stage with high precision. To move the stage I supply Sinusoidal wave using (Agilent Keysight) function generator. This F-gen, goes as low as \$20mV_{pp}\$ in ...
1
vote
1answer
66 views

Explanation for circuit with 2-stage op-amp, with diode in between first output and second input

I am a beginner in op-amp design and would like to get an explanation to a circuit that has a diode wired in between the output of op-amp-1 (stage 1) and the input of op-amp-2 (stage 2). The ...
0
votes
1answer
22 views

How to construct a LTI system with a specific impulse response function, say \$h(t) = \delta '(t)\$?

I want to ask the question on a generic basis, but using \$h(t) = \delta '(t)\$ as my example. I have Mathematical knowledge on the LTI system, but no hands on experience. In real life, how can we ...
0
votes
1answer
42 views

Crystal 4 Pins SMD footprint

I'm designing PCB that includes 24MHz SMD 4 pins crystal. According to my understanding, the crystal package marking is for Pin number 4. I wonder, how should I indicate in the PCB this pin? Should ...
-1
votes
0answers
66 views

Raspberry Pi zero project activated by 'unconnected' light switch

simulate this circuit – Schematic created using CircuitLab So i've just connected my first RPI project. It's pretty basic, essentially it takes completes a circuit on a pre-existing door ...
0
votes
0answers
32 views

Simple oscillator design not working when implemented

I thought this would be a quick build, but maybe there is something wrong with the design. Even though no waveform occurs, the MOSFET gets very hot. f = 1/(2π√[C(L1+L2)]) An n-channel 2N7000 MOSFET ...
0
votes
0answers
24 views

Resources for Common Circuit Configuration

I am an electronics newbie here. I used to build software that communicates with hardware interfaces like UART, digital/analog IO, etc. I know basic electronics and how to use common components. ...
0
votes
0answers
35 views

Differential amplifier amplifier design [closed]

I have a problem with the project of a differential amplifier that the teacher gives me. I have to do an amplifier with 3 stages: the first is a differential pair, the second is a common emitter and ...
0
votes
1answer
33 views

Changing AC amplitude and frequency

I'm working on a project for school to monitor a 6 and 15 VAC signal coming in at 11KHz for both. I'm trying to find a simple way of recreating that at home for running some tests on circuits I'm ...
0
votes
0answers
11 views

GF 22FDX - leakage during power rampup - run time issue

Hello, I was running power rampup simulations on GF22FDX to see leakage. I have used kernels (individual placables and not full macro). Its taking huge time to complete. It got killed after 1 day ...
0
votes
1answer
22 views

Circuit to a/b switch like a relay would. So an analog or digital signal can be turned on or off or routed

I need to build an arduino-based switcher / router for a multi-arcade to route controls to different game boards, and also switch 2 vga inputs into one output. Without introducing any lag also. 3 ...
0
votes
0answers
22 views

Can LM3914 be set up to work as an exclamation point and alarm flasher with a symmetrical input?

As the title implies I'm trying to make LM3914 to work as an exclamation point and alarm flasher. There is already a set up how to achieve both individually in the documentation from the LED bar ...
1
vote
2answers
63 views

How to find v through superposition theorem in the following ciruit

What is the voltage V of the attached circuit? Using super position theorem. When i active the 9V source & short 12 V source is the current follows in 20 ohms, 10 ohms. & 4 ohms? Or it only ...
0
votes
1answer
19 views

Can I use MCP23008 with G6K-2F-Y relay?

From specs of MCP23008: Maximum output current sunk by any output pin is 25 mA. Output High-Voltage is VDD-0.7, which is 4.3 V in my case. From specs of G6K-2F-Y: Rated current (mA) is 21.1 mA ...
0
votes
1answer
39 views

what does “ports can be registered” mean? For circuit design

I have a homework. I must design a circuit that makes addition with signed and unsigned numbers. I will use registers. I need two output ports. It says "8-bit output ports (2 ports: one for unsigned ...
1
vote
0answers
48 views

Resistor for buzzer current consumption limiting calculation

I would like to know how did the circuit designer of the circuit in the image calculated resistor R100 value. My guess is that the 100ohm resistor is to limit the current to ~20mA. I have tried to ...
0
votes
1answer
34 views

Analog logic circuit with adjustable threshold

I have a logic circuit currently consisting a few few AND gates and it's working fine (simulating) with if i use logic levels as the inputs. However my input levels might change in amplitude and I'd ...