The MAX7221ENG+ from Maxim Integrated Products is a serially interfaced, 8-digit LED display driver in in 24 pin narrow DIP package. It is a compact, serial input/output common-cathode display driver that interfaces microprocessors 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 also allow the user to select code-B decoding or no-decode for each digit. The device include a 150µA low power shutdown mode, analogue and digital brightness control, scan limit register that allows the user to display from 1 to 8 digits and test mode that forces all LEDs on. It is used in bar graph displays, industrial controllers, panel meters and LED matrix displays.
● Supply voltage range is 4V to 5.5V, operating temperature range from -40°C to 85°C
● Compatible with SPI, QSPI and MICROWIRE and has slew rate limited segment drivers to reduce EMI
● 10MHz serial interface
● Individual LED segment control
● Display blanked on power-up
● Operating supply current of 8mA at RSET = open circuit
● Display scan rate of 800Hz (8 digits scanned)
● Digit drive sink current of 320mA (V+ = 5V, VOUT = 0.65V)
● Digit drive leakage of -10µA, segment drive leakage of 1µA, segment current slew rate of 20mA/µs
● Individual digits may be addressed and updated without rewriting the entire display
