MAX7219CNG 8-Digit 7-Segment LED Display Driver DIP-24

MAX7219CNG 8-Digit 7-Segment LED Display Driver DIP-24 The MAX7219CNG is an 8-digit, 7-segment LED display driver DIP-24 is the IC housed in a 24-pin DIP package. It is designed for serial interfacing with microcontrollers and supports the control of up to 64 individual LEDs or eight 7-segment digits. The IC integrates a BCD code-B decoder, multiplex scan circuitry, segment and digit drivers, and an 8×8 static RAM to store each digit’s data. This chip simplifies LED display control by reducing the number of microcontroller pins needed to drive large displays, providing individual LED segment control, digital and analog brightness adjustment, and a low power shutdown mode that retains data. The MAX7219CNG operates with a supply voltage typically around 5V and supports a serial interface with data rates up to 10 MHz. It is widely used in applications such as digital clocks, counters, panel meters, bar-graph displays, and other LED matrix displays. Its slew-rate limited segment drivers minimize electromagnetic interference, enhancing display quality and reliability. The device is suitable for common-cathode LED configurations. The MAX7219 is an IC designed to control a 8×8 LED MATRIX. The IC is serial input common-cathode (Common Negative) display drivers that interface microprocessors (or microcontroller) to 7-segment numeric LED displays of up to 8 digits, bar-graph displays, or 64 individual LEDs. Features • Controls up to 64 individual LEDs or 8 digits of 7-segment displays with a single IC. • Serial interface (SPI-compatible) requiring only 4 wires for communication. • Built-in BCD code-B decoder for numeric digit control. • Multiplex scan circuitry for driving multiple digits efficiently. • On-chip 8×8 static RAM to store display data. • Adjustable segment current with a single external resistor. • Digital and analog brightness control for customizable LED intensity. • Low power shutdown mode (typical 150 μA) retaining data. • Slew-rate limited segment drivers reduce electromagnetic interference (EMI). • Scan-limit register to select the number of digits to display (1 to 8). • Display blanked automatically on power-up. • Common cathode LED display compatibility. • Operates from +4.0 V to +5.5 V supply voltage, recommended +5 V. • Maximum supply voltage up to 6 V. • Package: 24-pin Dual In-Line Package (DIP-24). • Typical applications include digital clocks, counters, bar graph displays, panel meters, and LED matrix displays. Pinout Configuration Pin Number: Description COMMON CATHODE OF DISPLAY SEGMENTS 2: DIG0- Common ground for all eight segments of DIGIT0 11: DIG1- Common ground for all eight segments of DIGIT1 6: DIG2- Common ground for all eight segments of DIGIT2 7: DIG3- Common ground for all eight segments of DIGIT3 3: DIG4- Common ground for all eight segments of DIGIT4 10: DIG5- Common ground for all eight segments of DIGIT5 5: DIG6- Common ground for all eight segments of DIGIT6 8: DIG7- Common ground for all eight segments of DIGIT7 SHARED TERMINALS 4: GND 19: V+- Power Supply SHARED SEGMENT TERMINAL OF ALL EIGHT DIGITS 14: SEG A – SEGEMTENT A of all DIGITS 16: SEG B – SEGEMTENT B of all DIGITS 20: SEG C – SEGEMTENT C of all DIGITS 23: SEG D – SEGEMTENT D of all DIGITS 21: SEG E – SEGEMTENT E of all DIGITS 15: SEG F – SEGEMTENT F of all DIGITS 17: SEG G – SEGEMTENT G of all DIGITS 22: SEG DP – SEGEMTENT DOT of all DIGITS FUNCTION PINS 1: DIN – Serial Data Input Pin 12: LOAD(CS) – Chip Select or Data shift pin 13: CLK – Clock Pin 24: DOUT – Pin used to Connect Second chip serially 18: ISET – current output adjust pin Specifications Specification: Value Operating Supply Voltage: 4.0V to 5.5V Recommended Operating Voltage: 5V Maximum Supply Voltage: 6V Shutdown Supply Current: Max 150μA Operating Supply Current: Max 8mA (RSET open) Digit Drive Sink Current: Max 320mA Segment Drive Source Current: -30mA to -45mA Display Scan Rate: 500Hz to 1300Hz Segment Current Matching: ±3% Maximum Digit Sink Current: 500mA per digit (absolute max) Maximum Segment Source Current: 100mA (absolute max) Operating Temperature Range: 0°C to +70°C (commercial range) Storage Temperature Range: -65°C to +160°C Package Type: 24-pin Narrow Plastic DIP (DIP-24) Serial Interface: SPI-compatible serial input/output How to use MAX7219 IC The chip is used similar to any shift register. First we will send serial data to chip bit by bit .once all data is sent we will tell chip to shift this serial data to output by enabling CS pin. The step by step procedure of working goes as below. • First connect DIN, CS and CLK pin. These three pins are important to controlling chip. • Next is selecting resistor for ISET pin. As we know that there is no standard parameter for segment displays in market. They have different voltage and current setting. In order to drive the display without error we will choose the appropriate resistor by using the following table. Forward voltage ISeg | 1.5V | 2.0V | 2.5V | 3.0V | 3.5V 40mA | 12.2kΩ | 11.8kΩ | 11.0kΩ | 10.6kΩ | 9.69kΩ 30mA | 17.8kΩ | 17.1kΩ | 15.8kΩ | 15.0kΩ | 14.0kΩ 20mA | 29.8kΩ | 28.0kΩ | 25.9kΩ | 24.5kΩ | 22.6kΩ 10mA | 66.7kΩ | 63.7kΩ | 59.3kΩ | 55.4kΩ | 51.2kΩ • There are two ways to use this chip. One is to follow the instructions given in datasheet to send the data bit by bit. Second way is to use libraries previously written for this chip. Using the libraries is easiest way to get the required result. With libraries you can just enter the required data to send without worrying anything. • We will send data to the chip through DIN pin. The data is sent BIT by BIT by setting the clock of chip for each bit. The Chip stores the serial data its registers until all data is received. After completing data sending we will set the CS pin for the chip to shift all data stored in its register to the output. • Once the data is put out by the chip it will light up the corresponding LEDs to display the result. Applications • Digital Displays Used in numeric and alphanumeric LED displays for clear numeric presentation. • Digital Clocks Facilitates precise control and multiplexing for clock digit displays. • Control Panels Used in industrial and consumer equipment panels for displaying status, data, or settings. • Digital Signage Suitable for driving up to 8 digits or bar graphs for information display in commercial signage. • LED Matrix Displays Supports matrix display control by driving up to 64 individual LEDs. • Panel Meters Ideal for numeric readouts in measuring instruments and meters. • Bar-Graph Displays Controls segmented bar graph indicators for visual status or level representation. Package Contents • 1 x MAX7219CNG 8-Digit 7-Segment LED Display Driver DIP-24 Datasheet • MAX7219