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I have a 4 digit LED display that I would like to integrate into my project, but only has 12 total pins when there are 4 digits. I am a beginner so I do not know how or which pins to power in order to display the required digits. Here are a few images of the LED Display. The number on the side is LD-5461BS.

If there is a configuration manual for this particular LED display, that would help as well.

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From some Googling this seems like a commonly produced module based around the CA-5461BS chip. It might have many manufacturers like the HD44780-based LCD module.

To summarise it's behaviour, it consists of four separate digits with a separate anode per digit and shared cathodes for each digit. See page 3 of the PDF.

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If you've got a little real estate to spare and you're not super cost-constrained, you could use one 8-bit shift register per 7-segment display. Using this approach and some smart bit-banging, you can run all 4 displays with just 3 pins.

I've seen a lot of hobbyists use the 74HC595 in such an application (see this example). It has a data out pin that supports cascading, so for 4 displays you have an 32-bit shift register across 4 devices. You clock the word into the register, then load it into the output buffers. This approach may be a little slower than a dedicated strobing IC, but it will be completely flicker-free.

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    \$\begingroup\$ This is a very useful way of doing things for hobbyists, the users learn a whole lot of practical digital electronics with it. +1. \$\endgroup\$ – Trygve Laugstøl Nov 23 '12 at 8:12

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