The MAX7219 is an all-in-one LED Matrix driver suitable for controlling an 8x8 LED Matrix or even eight 7-segment displays (BCD decoding can be done on the chip too).When you need some help driving a lot of LEDs, the MAX7219 is the best friend you could hope for. If you want to control a large number of LEDs, you'll want to use multiplexing, a technique that allows you to control 64 LEDs (for example) with only 16 pins (8x8). The annoying thing about 'plexing is that you need to use 8 power transistors (or a power register/latch, that can supply over 100mA per pin) AND you have to constantly refresh the display to keep the image stable. If you need to get something together quickly, or don't want to bother with writing all that code, and especially if you want clean wiring, this chip is the ideal solution.The MAX7219 does all the control and refresh work for you in driving either an 8x8 matrix display or 8 x 7-segment displays (usually these also have a dot, so it's really an 8-segment display) - 64 LEDs total. All you have to do is send it serial commands via the 4-pin SPI interface and it will auto-magically take care of the rest. Wiring is simplified as well, you only need to set the current level for all LEDs with a single resistor instead of 8 and you can also dim the entire display digitally. It's a thru-hole chip so you can use it in any breadboard, perfboard, or other projects, although if you're soldering it in, we suggest using a socket.Product Marking: MAX7219CNG.
