# Tagged Questions

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58 views

### solder individual LEDs to form an X for a visor [on hold]

I'm looking to find a way to make an LED display to form two X's. This display is to be implemented into a tinted visor (similar to a daft punk visor), so I was looking to connect the LEDs ...
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### 8x8 switched diode matrix not behaving

I'm trying to read a matrix of switches. Attached is the circuit I've designed, the pertinent section being on the right driven by the 4041s. I'm using 1N4148 diodes. What I've found is that if I ...
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### Name for operations performed on Jacobian matrix to optimize calculation

When conducting Load-flow analysis, using the Newton-Raphson iterative method, one of the key steps is generating a Jacobian matrix (based on the active and reactive powers of the elements and regard ...
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### 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 ...
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### 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 ...
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### 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 ...
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### 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. <...
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### Brightness issues driving 10*11 SMD 5050 LEDs matrix

I'm working on driving a 10*11 LEDs matrix by a µC since a while, and I decided to come to you because I'm a bit surprised/annoyed by my results. So, I first started with simple 5mm white LEDs ...
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### Why aren't SRAM modules laid out in a matrix?

I'm currently reading about RAM modules. Bigger DRAM module are laid out in a matrix. When retrieving data you first retrieve the row and then the column. One of the benefits of the matrix lay-out is ...
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### Need help setting up 7X6 Piranha LED Matrix with Arduino

I need help correctly getting my parts list for a 7X6 matrix that will be part of a electronic outdoor scoreboard. Here is my parts list so far but I am stump whether the arduino is powerful enough ...
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### How to drive 32-by-32 (or more) LED matrix? [duplicate]

I have a matrix of 32-by-32 LEDs that I need to control using a driver. The largest driver that I found was a 16-by-16 driver by Linear Technology, and there is no driver that goes higher than 16-by-...
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### LED Multiplex Anode-Row Driver

I'm helping build this art installation that amounts to a large 16 x 16 pixel display. I settled on using 16 TI TLC5926 constant current driver chips chained together to give me direct drive to each ...
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### Connecting a N.O. grounded switch to a scanning switch matrix

I am working on a project that includes a scanning switch matrix. It also includes a joystick with an integrated push button. I am out of IO pins on the micro, but there are gaps in my switch matrix, ...
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### How does the ZX80 keyboard avoid ghosting and masking?

I believe that a keyboard matrix needs a diode on each key to avoid ghosting and masking. http://pcbheaven.com/wikipages/How_Key_Matrices_Works/ The ZX80 (and probably ZX81) has only a diode for ...
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### How to Create an RGB LED Display for Raspberry Pi?

I'm relatively new to hardware. I have some basic concepts down and I've only done some basic circuitry, but I really want to jump into the deep end - it's how I learn best. I'm not sure how simple ...
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### How Can I Program an LED Matrix

I got this really cool idea the other day. Sitting in my Computer-Sci Lab at school I saw the binary clock on the wall. As a "watch guy", I immediately wanted a watch like it. I've always had a DIY ...
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### Using a TLC5940 to control LEDs with different forward voltages

I am trying to build an LED matrix (64x32) of RGB LEDs using a TLC5940 current sink LED driver. The forward voltages of the LED components for each RGB LED are: R: 1.8V G: 2.8V B: 2.8V The driver ...
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### How does an LED matrix work?

I've wired up a 3x3 matrix as in the attached image. My understanding is that if I apply 3.3 volts to row C and connect column 1 to ground, the electricity should flow through the bottom-left LED (as ...
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### 20x20 RGB LED Matrix controller project

I've been wanting to start a project with the following requirements: Be able to display a static image, composed of 19x19 RGB pixels (though I expect to have to use a 20x20 matrix). Be small (in ...
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### How to hook up circuit to drive 5x7 1 Watt White LED

I am not a electronics guy but want to design a display using 5x7 Ultra Bright 1.2 W, 350 mA OSRAM DRAGON-X Plus LED. I want to have a simple circuit so as to be able to control (Switch ON/OFF) ...
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### Routing Current to Many Individual Channels [duplicate]

Possible Duplicate: How to implement an isolated connection matrix I need to put current on up to 30 lines; one at a time. What kind of electronics solutions are there to this kind of problem....
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### How do I control several hundred individual leds with Arduino(s)?

I am working on an electronics project which involves hundreds of LEDs. (Talking upwards of six to seven hundred LEDs...a lot, I know.) Is there any way to control this many LEDs with one or a couple ...
1k views

### Led Matrix using PIC

For a project I am working on, I want to build a 9x9 monocolor LED matrix also with 9 push buttons to control the LEDs using the PIC. So far I have gathered that I think I will be needing shift ...
1k views

### How to control and power 25 x 25 nichrome wire matrix

I would like to control and power a 40x40mm size array of 25 x 25 small heating elements which should function just like a visual display of LEDs, but switching heating elements on/off instead. I am ...
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### Driving a common cathode 8x8 RGB LED Matrix with PWM

I've got this nice RGB LED Matrix. My goal is to use several of them to create a 16x16 color display. Unfortunately, the display is common cathode. From experiments driving a single LED with 8-bit ...
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### How can I matrix switch multiple lines, including power?

I have devices with several similar boards, all of which are basic computers (with CPU, RAM and ROMs etc.). They all interface to the I/O unit via a standard connector, although the connectors aren't ...
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### Rotating a gyroscope's output values into an earth-relative reference frame

For whatever reason, I seem to have gotten myself twisted into quite a confusion on how to process data from my 3 axis gyro and 3 axis accelerometer to get gyro rotation values related to the earth's ...