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Questions tagged [max7219]

The MAX7219/MAX7221 are compact, serial input/output common-cathode display drivers that interface microprocessors (µPs) to 7-segment numeric LED displays of up to 8 digits, bar-graph displays, or 64 individual LEDs

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Max7219 segment drivers output voltage is lower than expected

I'm using a max 7219 to control 7 highside drivers (which provides power to two higher voltage common cathode displays). The components on my breadboard are connected according to this schematic: The ...
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How to interpret MAX7219 timing diagram?

I'm trying to connect this module to atmega32u4 (16 MHz): Everything seems mostly working, but I have a question: how much time is needed for the latch to take effect? I.e., is a delay needed between ...
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MAX7219, SPI capable/Timing question?

So I purchased a cheap Double-7-Segment display piece (specifically this one: https://www.amazon.com/dp/B01D0WSCJA) To do some tinkering with. I've messed around with it manually to make sure it ...
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7-Segment Drivers: How do they work/how to handle them?

So I know to drive a 7-segment display you need a TON of pins. However there are 7-segment display drivers (such as the MAX7219) that seem pretty popular. However I'm looking at the datasheet, and am ...
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Maximum MAX7219 wire length to LEDs?

I'm intending to make a multiplexed 128 LEDs 'ceiling light', which has LEDs randomly spread out over a 2 by 1 meter area. For this I need two MAX7219 ICs, so they can handle 64 LEDs each, where ...
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MAX7221 not always powering on

I have a MAX7221 SPI 7-seg. LED driver linked to an AVR168P microcontroller. Sometimes when powering on, everything works as expected. Other times the display blanks and remains blank. Other times ...