7448 IC – BCD to 7-Segment Display Decoder/Driver
🔲 7448 IC – BCD to 7-Segment Display Decoder/Driver (Common Cathode)
The 7448 is a TTL logic BCD (Binary-Coded Decimal) to 7-segment decoder/driver specifically designed for common cathode displays. It accepts a 4-bit BCD input and activates the appropriate segments (a to g) to display decimal numbers 0–9 on a 7-segment LED display.
⚙️ Technical Specifications
| Parameter | Specification |
|---|---|
| IC Type | BCD to 7-Segment Decoder/Driver |
| Display Compatibility | Common Cathode |
| Logic Family | TTL (74 series) |
| Inputs | 4-bit BCD (A, B, C, D) |
| Outputs | 7 control outputs (a to g), active HIGH |
| Output Type | Open collector with internal drivers |
| Supply Voltage (Vcc) | 4.75V to 5.25V (typically 5V) |
| Package Type | DIP-16 |
| Operating Temp Range | 0°C to +70°C |
📌 Pin Configuration (DIP-16)
| Pin | Function | Pin | Function |
|---|---|---|---|
| 1 | B (Input) | 16 | Vcc |
| 2 | C (Input) | 15 | Segment a |
| 3 | LT (Lamp Test, active LOW) | 14 | Segment b |
| 4 | RBI (Ripple Blanking In) | 13 | Segment c |
| 5 | D (Input) | 12 | Segment d |
| 6 | BI/RBO (Blanking Input/Output) | 11 | Segment e |
| 7 | A (Input) | 10 | Segment f |
| 8 | GND (Ground) | 9 | Segment g |
🧠 Truth Table (Sample)
| Input (DCBA) | Displayed Digit | Segments Activated (a–g) |
|---|---|---|
| 0000 | 0 | a b c d e f |
| 0001 | 1 | b c |
| 0010 | 2 | a b g e d |
| 0011 | 3 | a b c d g |
| ... | ... | ... |
| 1001 | 9 | a b c d f g |
Segments are active HIGH for common cathode displays.
🛠️ Applications
Digital clocks and counters
7-segment display driving
Arduino and microcontroller projects
Basic calculators
Learning tools for digital electronics
⚡ Notes
Use current-limiting resistors between outputs and display segments.
Designed for common cathode 7-segment displays (unlike the 7447, which is for common anode).