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Questions tagged [7segmentdisplay]

A numeric display consisting of seven segments per digit, allowing characters 0 to 9 to be displayed by selecting which segment is on or off. Can have each digit independently controlled, or can be multiplexed to reduce pin count. An 8th segment can be included for a decimal point.

Typically referring to LED or LCD displays where 7 segments can be combined to display a numeral between 0 and 9. LED Displays may be arranged as either common anode or common cathode, with independently broken out pins, or multiplexed to reduce pin count.

Typical arrangement of segments:

enter image description here

Another representation of the 7-segment character showing pinout, circuit diagrams for common anode models and common cathode models:

enter image description here

(Source)

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Why do 7 segment LED displays break apart when I brush my teeth?

This question might sound silly, but it is very serious (although geeky, I must admit). When I use my electric toothbrush in front of my alarm clock (one of those with a big red LED display), the numbers seem to break apart. Why? With my current…
Max
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Why does the seven segment display have decimal point at the right?

All the seven segment displays I’ve seen so far have their decimal point to the right of the main digit. Why is this so? A decimal point to the left will be able to represent more possible combinations of numbers. A single digit display with a…
Atom
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Why did my LED resistor burn while lighting four LEDs in series?

I have tried to create a circuit to switch a large 7-segment LED display (LDS-CD16RI) using a pair of MOSFETs, as follows: simulate this circuit – Schematic created using CircuitLab Here I am trying to use a 3.3V logic signal (illustrated as the…
Martin Atkins
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Seven-segment display seems to draw little current

I bought a 1.8-inch seven-segment common cathode LED display from AliExpress. So no datasheet available. I used a 1 kΩ resistor and a 5 V source, as to put a max 5 mA in the LED. I measured 1.6 V for the decimal dot, and 3.5 V for each segment. The…
mathieu
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Low power, seven segment display

I want to display a 4 digit number on a small device that fits in a hand. I have a CR2032 3V battery at around 230mA, my microprocessor is a 8051 (in a BLE112) usually uses about 0.9µA and I want the device to last as long as possible. I've looked…
Hink
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Using 4 digit 7 segment LED

I have a 7 segment display that has 4 digits. What will I need to make use of this? Can a single microcontroller handle the operation? I mean PIC16F690...I saw also a MAXIM chip that drives these kind of displays...is it absolutely required? Here is…
Dumbo
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4026 + 7-segment display: do I need transistors?

I'm a beginner and, as an exercise, I'm building a digital clock using without a microcontroller. The main IC that I'm using is a 4026, which counts and converts do 7-segment led format. The leds in the 7-segment glow very dimly. I'm reading the…
André Wagner
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Improving brightness of multiplexed 7-segment led display

I have a two digit 7-segment LED display which is driven multiplexed by a microcontroller. PORTA is for the anodes. In my code I shift a 1 through PORTA. On PORTB I say which segment should light by setting it to 0. My problem is that the display…
arminb
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Reverse engineering a 12 pin LCD?

I just found a broken "laser projecting alarm clock". I took it apart, and am interested in only the laser projection arm. This consists of a laser diode (although I suspect that this is actually just a normal LED), a small LCD screen, and a plastic…
naught101
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Why can't resistors be used to connect cathode pins to GND instead of segment pins to VDD with a 7-segment display?

When using a common cathode 7-segment display, is there a reason that two resistors can't be used to connect the two cathode pins to GND instead of using seven resistors to connect the seven anode pins to VDD? I'm assuming there's a good reason,…
Nate
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7-segment LED display with multiple digits

I was looking at the datasheet for the LTC-4627JR, and it looks like each digit shares a common anode, and each segment shares a common cathode. My question is given this configuration, I don't understand how to drive each digit separately. For…
helloworld922
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LCD modules with I2C or SPI interface

I would like to add an LCD to my current design (a project that is to be produced in low volume, around 50 to 100 units). A small display size (around 8 or 16 characters) should be plenty since it is for measurement readout, and I would like to keep…
boardbite
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Multiplexing 2 digit 7Segment with one Bit

I want to control a 2 digit 7-segment LED with a MSP430 micro controller. The display has 8 input pins per digit (8th pin is the dot, which I do not need) and two ground pins (common cathode). The idea is to connect the first 7 pins from the µc to…
A.Schulz
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Multiplexed Display

Need to develop a user display for a home appliance with: Two digit temperature display (Seven Segment). Four LEDs for 'Power ON' and three 'Modes of Operation' of the appliance. I came across a design in one of the older units (Modified schematic…
Sohail
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7 segment binary to hex

I'm trying to display a 4-bit binary number on a 7 segment LED as a hexadecimal number (0-F). I have an assortment of 7400 series ICs including the 7447. But that one only works for BCD (0-9). The 7400 series doesn't seem to have a hex to 7-segment…
Goswin von Brederlow
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