Description

The MAX7219 / MAX7221 are compact, serial input / output
common-cathode display drivers that interface
microprocessors (μPs) to 7-segment numeric LED displays
or 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-ratelimited
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 scanlimit
register that allows the user to display from 1 to 8
digits, and a test mode that forces all LEDs on.

Features

10MHz Serial Interface
Individual LED Segment Control
Decode / No-Decode Digit Selection
150μA Low-Power Shutdown (Data Retained)
Digital and Analog Brightness Control
Display Blanked on Power-Up
Drive Common-Cathode LED Display
Slew-Rate Limited Segment Drivers for Lower EMI (MAX7221)
SPI, QSPI, Microwire Serial Interface (MAX7221)
24-Pin DIP and SO Packages