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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. Included on-chip are a BCD code-B decoder, multiplex scan circuitry, segment and digit drivers, and an 8x8 static RAM that stores each digit. Only one external resistor is required to set the segment current for all LEDs. The MAX7221 is compatible with SPI™, QSPI™, and Microwire™, and has slew-rate- limited segment drivers to reduce EMI.
A convenient 3-wire serial interface connects to all common µPs. Individual digits may be addressed and updated without rewriting the entire display. The MAX7219/MAX7221 also allow the user to select code-B decoding or no-decode for each digit.
The devices include a 150µA low-power shutdown mode, analog and digital brightness control, a scan-limit register that allows the user to display from 1 to 8 digits, and a test mode that forces all LEDs on.
wanna an advise?... this MAX IC's are great but they're extremelly expensive to a simple 7 segment ckt.... I'd advise you to use a 4511, some analog switches and some BC337 to do the job, simple, clean, easy to find and CHEAP....
Many years ago I made such display, using 74188 PROM like hex - BCD convertor. Because I made signature analyzers, I needed some decoder like 74145, but to yield readable codes on 7 segment indicator. For sure you can get now many other PROMS.
Then you need generator for scanning, one register of 74173 (with TRISTATE)... for every digit - one chip.
Now, when having PIC for me will be 2-3 or less hours job to make such display. So, if you asking me - try to implement some uP. Cheaper, better, faster... any kind of digits, less elements.