Seven Segment LCDs?


Has anyone had any luck hooking up seven segment lcds to their arduino's? These have 4 seven segment digits, a :, and an am/pm display. They have less than 28 pins.

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LCDs have a bit of a trick to them, because they need AC to drive them. It doesn't take much, but you need to drive the backplane with a swtiching pin on the arduino. And of course, without a driver chip, you need a pin per segment + a mulltiplex.
First of all a seven segment display and an LCD are totally different types of displays. LCD stands for Liquid Crystal Display.
Michael_Bell (author)  mpilchfamily5 years ago

"Seven-segment displays may use a liquid crystal display (LCD), arrays of light-emitting diodes (LEDs), or other light-generating or controlling techniques such as cold cathode gas discharge, vacuum fluorescent, incandescent filaments, and others." Thank You Wikipedia :)

Im talking about the LCD's that you would find in something like a coffe maker that displays the time in the format 12:12 am

They are capable of displaying 88:88 and am/pm

Sorry for the confusion
My microwave uses LED display However if you have LCD (Gery when off) then disregard my original post as it doesn't apply to LCD.
No, you can buy 7 segment LCDs !!

rickharris5 years ago
Find a data sheet, You need to know if they are common anode or common cathode.

Beyond that you have a bunch of LEDs that just happen to be formatted in a numerical pattern so lighting them is straight forward.

As F'ard says to drive as a numerical display usually it is easier to use a driver chip - send the number in binary to the chip and it sorts out the logic for the display.

the 4026 is one such beast - Data sheet here

frollard5 years ago
You usually need to drive them with either a demultiplexer (you feed in one of 10 pins and it outputs the correct number for you), or drive the matrix yourself and decode the pins yourself.

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