MAX7219 8-Digit LED Display Driver
Compact, serial input/output common-cathode display driver interfacing microprocessors to 7-segment numeric LED displays up to 8 digits, bar-graph displays, or 64 individual LEDs.
Aliase:MAX7219CNG, MAX7221, 8x8 LED Matrix Driver, 7-Segment Driver
DIP-24 Top View
24 Pins
Pin-Tabelle24
| Pin | Signal / Name | Typ | Alternative Funktionen |
|---|---|---|---|
| 1 | DIN | Digital | Serial Data Input — data latched on CLK rising edge; MSB first; 16-bit word (address + data) |
| 2 | DIG 0 | Digital | Digit 0 Common Cathode Driver — sinks current from digit 0 LED cathodes; LOW selects digit |
| 3 | DIG 4 | Digital | Digit 4 Common Cathode Driver — sinks current from digit 4 LED cathodes; LOW selects digit |
| 4 | GND | Ground | Ground (0V) — connect both GND pins to ground plane |
| 5 | DIG 6 | Digital | Digit 6 Common Cathode Driver — sinks current from digit 6 LED cathodes; LOW selects digit |
| 6 | DIG 2 | Digital | Digit 2 Common Cathode Driver — sinks current from digit 2 LED cathodes; LOW selects digit |
| 7 | DIG 3 | Digital | Digit 3 Common Cathode Driver — sinks current from digit 3 LED cathodes; LOW selects digit |
| 8 | DIG 7 | Digital | Digit 7 Common Cathode Driver — sinks current from digit 7 LED cathodes; LOW selects digit |
| 9 | GND | Ground | Ground (0V) — connect both GND pins to ground plane |
| 10 | DIG 5 | Digital | Digit 5 Common Cathode Driver — sinks current from digit 5 LED cathodes; LOW selects digit |
| 11 | DIG 1 | Digital | Digit 1 Common Cathode Driver — sinks current from digit 1 LED cathodes; LOW selects digit |
| 12 | LOAD | Digital | Load / Chip Select (LOAD on MAX7219) — rising edge latches last 16 bits into registers; equivalent to ~CS (Active Low) on MAX7221 |
| 13 | CLK | Digital | Serial Clock Input (max 10MHz) — DIN sampled on rising edge; DOUT shifts on falling edge |
| 14 | SEG A | Digital | Segment A Anode Driver — sources current to segment A of all digit positions; HIGH = segment ON |
| 15 | SEG F | Digital | Segment F Anode Driver — sources current to segment F of all digit positions; HIGH = segment ON |
| 16 | SEG B | Digital | Segment B Anode Driver — sources current to segment B of all digit positions; HIGH = segment ON |
| 17 | SEG G | Digital | Segment G Anode Driver — sources current to segment G of all digit positions; HIGH = segment ON |
| 18 | ISET | Analog | Peak Segment Current Set — connect resistor between ISET and V+ to set LED drive current; R_ISET = (V+ − 1.5V) / (I_seg / 100); typical: 9.53kΩ for 40mA peak |
| 19 | V+ | Power | Positive Supply Voltage (+4.0V to +5.5V; add 100nF + 10µF bypass caps to GND near pin) |
| 20 | SEG C | Digital | Segment C Anode Driver — sources current to segment C of all digit positions; HIGH = segment ON |
| 21 | SEG E | Digital | Segment E Anode Driver — sources current to segment E of all digit positions; HIGH = segment ON |
| 22 | SEG DP | Digital | Decimal Point Anode Driver — sources current to decimal point segment of all digit positions; HIGH = DP ON |
| 23 | SEG D | Digital | Segment D Anode Driver — sources current to segment D of all digit positions; HIGH = segment ON |
| 24 | DOUT | Digital | Serial Data Output — connects to DIN of next MAX7219 for daisy-chaining multiple devices; data propagates with 16.5 CLK cycle delay |