Questions tagged [matrix]
The matrix tag has no usage guidance.
1
vote
1answer
91 views
Matrix of small incandescent lightbulbs - problem with buzzing
I am prototyping a circuit for controlling matrix display of small incandescent lamps with Arduino (each lamp is 6.3V 0.3A). I designed the circuit in Yenka and built it. It is composed from 3 types ...
0
votes
1answer
38 views
Node analysis with voltage source in matrix form
simulate this circuit – Schematic created using CircuitLab
Can you please check if my reasoning is correct?
The sum of currents leaving node k is:
$$ I_k = \sum_{i = 0}^{n} I_{ki} = \sum_{i = ...
1
vote
0answers
44 views
How to get relative rotation matrix from two consecutive orientations of MPU6050
I need to find the relative rotation matrix between two orientations of MPU6050. My approach (which fails) uses the MPU6050 quaternion from jrowbergs code. Let quaternion at orientation 1 be q1 & ...
0
votes
1answer
113 views
Finding Z-parameters from a two-port network and using them to find S-parameters
So I have the two-port network
and I want to find out the Z-parameters of it (and later, use that to find the S-parameters). For the assignment, \$R_x=8Ω\$.
From what I understood, I should null ...
0
votes
0answers
26 views
s-parameter matrix analysis
So I'm trying to figure out how I can analyze S-parameter matrices.
The i. should be pretty straightforward, though I'm not 100% sure if I am correct with what it means. I'm assuming that there's ...
1
vote
2answers
60 views
Row Column Matrix Problem with Flyback Diodes
So I had a simple row column matrix which I am driving with mosfets to power solenoid locks like this:
GC is ground via 1.5k resistor
C is 24V via 1.5k resistor
And these are the connectors:
...
0
votes
2answers
42 views
Can I in any way connect +ve side of my led to uln2083a output pin?If no can I do it with M54562 transistor array?
I had conneced my digital pin of arduino to the uln2803a to drive LED. I want to configure my uln2803a such that i can connect +ve side of the led to the output pin of uln2803a IC.
2
votes
2answers
82 views
Unusual behavior when controlling a Button Matrix
I have a 4x4 matrix for 16 buttons. Each row/column is directly connected to the pins of an unknown microcontroller. When I connect the pins directly to each other, the microcontroller behaves ...
1
vote
1answer
85 views
How to solve a circuit network involving a resistor parallel to a voltage source using only nodal analysis?
I have been stuck on this for the past week and this week i just dont seem to find out what am i doing wrong. Please help me spot my mistake. Here you can find My circuit on multisim. Please provide ...
0
votes
1answer
40 views
Connect 3-port and 1-port devices defined by S-matrices
There are two linear networks.
The first is defined by 3-port S-matrix:
\$\mathrm{S}_\mathrm{A} =
\left[
\begin{array}{lll}
s_{11} & s_{12} & s_{13} \\
s_{21} & s_{22} & s_{23} \\...
1
vote
1answer
279 views
Vertical ghosting on 64x32 1/16 RGB LED matrix panel
I have been working at driving some of those generic LED matrix panels found all over the web for sale (such as this one), 64x32
I've struggled a lot with the lack of real documentation, but I've ...
0
votes
1answer
122 views
9X9 RGB Led matrix, design suggestion
I need to drive 80 RGB leds (so 240 individual leds), physically and conceptually aligned as an 8x8 matrix + an additional vertical line and an additional horizontal line.
I'd like to drive the ...
0
votes
1answer
135 views
8051 program not processing keypad matrix correctly
I made myself a small PCB (measuring about 6cm by 5cm). This is what is supposed to happen:
Upon power-up, the LED goes red to indicate that the unit is ready for input.
I then press any key down (...
1
vote
1answer
77 views
S - parameters or scattering matrix
i have written in dsp.stackexchange.com, but guzs have written me this question would be better off on this site.
I have questions according to how to measure s- parameter.
I have a two-port ...
9
votes
2answers
717 views
Is this matrix-vector multiplication function in VHDL parallelized?
I have the following VHDL function that multiples a given mxn matrix a by a nx1 vector b:
...
1
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2answers
183 views
Reviving / upgrading a commercial LED sign
I have a commercial LED sign that in its stock format is only controllable by IR remote (the remote is long gone). I'm trying to create a new controller for it so I can push data from one of our ...
0
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0answers
53 views
Obtaining the analytical expression using the state transformation matrix
I am trying to derive the analytical expression in the box below. T is the state transformation matrix.
x_dot=A*x(t) is a second order linear system.
A has 2 distinct eigenvalues s1 and s2 and ...
1
vote
1answer
394 views
LED and Button Matrix multiplexing?
I have only six GPIO to control a piezo buzzer and 6 LEDs and read 6 buttons...
Would multiplexing the 6 LEDs/buttons in a 2x3 matrix work like this (i.e. 5 pins for the 6 LEDs and buttons, one ...
0
votes
2answers
172 views
Why does this rotary switch register multiple positions simultaneously?
New to electronics, tackling a project that involves a switch matrix.
Having grasped the concept of regular button matrices and modifier keys, it’s time to move on to explore alternative types of ...
0
votes
1answer
47 views
Controlling 8x8 matrix mounted lamp [closed]
This is an hypothetical question, not for the real build.
Let say there are 64 filament bulbs runs on AC 240V mounted in 8x8 matrix pattern. These lamps are to be controlled by only 16 switches (8 ...
-1
votes
2answers
2k views
Very big matrix multiplication in FPGA
I'm working with convolutional neural networks and I have written a code to make the convolution of two 3x3 matrices. This is my code: https://www.edaplayground.com/x/6G7h
Now I want to make the ...
0
votes
3answers
309 views
Digital potentiometer mixing matrix
I need to mix 4 analog inputs with different weights into 4 analog outputs with audio application in mind. This can simply be made using potentiometers and opamps for buffering, like shown on the ...
0
votes
1answer
57 views
What is the mathematical difference between a transfer function and a state transition matrix?
I do know what the difference in meaning is between a transfer function (output over the input) and a state transition matrix $\Phi$ (describes the unforced response of the system). Yet when looking ...
0
votes
0answers
124 views
Diode populated keyboard matrix: Wire two separate buttons to the same output?
I have an encoder board for a 16x8 row/column switch matrix.
An absolute beginner to electronics but using all of the great online resources for research the best I can. However, occasionally it turns ...
1
vote
2answers
496 views
8x8 LED Matrix re-build
the company i work for has tasked me in rebuilding an old LED sign we had replaced. (newer led rgb version) The driver board that was in the sign has gone out. So i am trying to rebuild the driver ...
0
votes
1answer
81 views
Setting ground potential in nodal analysis matrix form
I have a general question concerning the matrix formulation of nodal analysis.
I investigate a large resistor network with tens of thousands of resistors and some independent current sources.
I set ...
1
vote
0answers
149 views
Is there any way to do matrix/vector algebra with analog electrical components?
Is there any way to do matrix/vector algebra with analog electrical components?
Only addition, subtracting and multiplying.
I'm going to build a Linear-Quadratic-Gaussian(LQG) Controller.
2
votes
3answers
554 views
How can I read an large array of switches with some microcontroller?
I have been asked by someone whether or not I could do some programming on a large array (something like 18 x 16) of analogue switches.
I would want to wire up an array of analogue switches (you know,...
0
votes
1answer
152 views
IEEE 4 machine system: Need help in computing the bus admittance matrix
I need help in computing the bus admittance matrix for the following Kundur's 4 machine 2 area system:
...
1
vote
1answer
318 views
Equivalent resistance of Resistor measurement matrix
To measure a lot of (high resistance) resistors in an harsh environment, I want to setup a matrix of these resistors under test (\$R_{00} \dots R_{nm}\$).
The resistors \$R_{x0} \dots R_{xn}\$ and \$...
9
votes
4answers
4k views
How can 16 buttons be connected with only 8 wires?
Here is the product. I understand the idea: these 16 buttons use a 4x4 matrix. 4 lines for rows, 4 lines for columns, and we have 8 cables.
But:
How can this work without any multiplexer ?
Can this ...
1
vote
2answers
273 views
Building a 20x20 matrix with vibrator motor coins
I am currently doing a project that requires a 20x20 matrix with coin type vibrator motors.
I am not sure how to pull this off. What is the best way of driving all the motors all together? Provided ...
5
votes
4answers
2k views
74HC595 Rows/Columns to drive LED matrix
Let's say we have one 74HC595 and we want to light 16 leds (common anode) connected as a 4x4 matrix exactly as in the following picture :
So, 4 first outputs to controls 4 rows.
The remaining 4 ...
16
votes
1answer
689 views
Studying the PCB of a 70s calculator. What were they thinking?
I've been studying the PCB from an ELSI 8002 calculator from 1974. I'm thinking of repurposing the case for a project, though now that I've fixed it (by re soldering the battery connectors) I don't ...
1
vote
2answers
2k views
Creating a DC resistor network matrix
I have the following resistor network and I need to make a 7x7 matrix which would be the solution . I know the resistor values, but not the v1, v2, v3 or any of the current. I'm supposed to combine ...
0
votes
1answer
432 views
Certain property of a bus admittance matrix
I have got a simple network for my assignment:
I know bus admittance matrix have certain properties that let us form the matrix without writing so many lines of KCL...
-3
votes
1answer
77 views
Simple Matlab Problem [closed]
I just started working with Matlab last week, so I'm very new. After searching for a while, I realized that I don't know how to fix a Matlab script that I'm working with. The problem is given below.
<...
2
votes
2answers
212 views
state-space model of non-linear system?
This is the equation for which I have to make a state-space model.
$$m\ddot y(t)+b\dot y(t)+k_1y(t)+k_2y(t)^3=u(t)$$
For my A matrix I have
$$\begin{bmatrix}
0 & 1 \\
? & \frac{-b}{m}\\
\...
0
votes
1answer
148 views
Interfacing thousands of RGB LEDs in a matrix
So I have 3072 RGB LEDs I need to connect in a matrix.
I have decided to split the project into smaller matrices and all LEDs are common Anode.
Datasheet for LEDs is here:
http://docs-europe....
15
votes
5answers
3k views
Making an electronic chess board
I want to make a wooden chess board that you can play on with regular pieces (i.e., not modified pieces that make use of RFID codes, magnets, …), but that is connected to a software that takes notice ...
1
vote
0answers
108 views
col not declared issue{Verilog}
I am having a problem here can't make this code compile. It is a 4x4 keypad scanner with a 20ms debouncer. It gives error "Error: 'col' has not been declared"
Any suggestion?
...
0
votes
1answer
430 views
4x4 keyboard matrix not generating unique keycodes
I have a 4x4 keybord matrix fsm scanner but it generates only high keycode setting all last 4 bits to 1 and second and fourth digits to high.
Is there anything wrong in my code here?
...
1
vote
1answer
825 views
How to write a counter in verilog for debouncing an input?
I am trying to write a module counter to debounce a input coming from mechanical buttons. The module should be controlled by the 4x4 matrix button module when to start or stop debonce.
This is my ...
0
votes
2answers
1k views
Why is my Verilog code for 4x4 button matrix not scanning?
I have a problem with a module in Verilog where I need to scan a 4x4 button matrix. I don't get to scan each row 1 by one but the thing stick with the first row. Can you help me debug it? To me it ...
1
vote
2answers
422 views
Mesh Current method for solving a variable resistor?
I have a circuit with a variable resistor R which I need to find the value of. I am told that the power dissipated in the resistor is 250W.
The circuit:
I used the mesh current method naming the ...
0
votes
2answers
198 views
Illuminated SPST Switch
I am building a HID device (for flight/space simulators) with an Arduino Micro that will have a 7 column and 4 row matrix plus 4 axes. I have the matrix working fine with normal buttons and switches ...
2
votes
1answer
147 views
Physical significance of singular matrix in two port network
In class we've been introduced to two port networks, and I was wondering: Is there a physical significance to a singular matrix in a two port network, or is it simply where the mathematical model ...
1
vote
1answer
5k views
Keypad Scanner Verilog code problem with state machine and column input
I am developing a Keypad both in hardware and Verilog using a DE2 Cyclone II board. I made a keypad using buttons (switches) that follows this schematic:
The scanner works by setting the Column ...
1
vote
1answer
73 views
how to calculate Hermitian Toeplitz system of equations on fpga in vhdl
I'm trying to write vhdl code to solve the Hermitian Toeplitz system of equations (solving for the A's).
...
0
votes
3answers
2k views
How to calculate power requirements of LED matrix, per row or per LED?
I have built an LED matrix (9x9) and want to run it with Arduino. I am using technique of scanning, lighting up 1 LED at 1 time.
The more I am reading about power requirements of a matrix the more I ...
