The Texas Instruments CD40147BE is a BCD (Binary-Coded Decimal) to 7-segment latch decoder/driver. It is designed to convert a 4-bit binary input into a corresponding decimal output that can drive a 7-segment display. This device is particularly useful in applications where numerical displays are required, such as digital clocks, calculators, and other electronic devices that display numerical information.
## Key Features
1. BCD to 7-Segment Decoding: The CD40147BE takes a 4-bit BCD input and decodes it into a 7-segment output, allowing for easy display of decimal numbers from 0 to 9.
2. Latch Functionality: The device includes a latch that holds the output state, which is useful for maintaining the display without continuous input changes.
3. Active Low Outputs: The outputs of the CD40147BE are active low, meaning that a low signal (0) will turn on the corresponding segment of the display.
4. Wide Supply Voltage Range: The device operates over a wide supply voltage range, typically from 3V to 15V, making it versatile for various applications.
5. Low Power Consumption: The CD40147BE is designed for low power consumption, which is beneficial for battery-operated devices.
6. High Noise Immunity: The device features high noise immunity, ensuring reliable operation in noisy environments.
## Specifications
- Supply Voltage (V_DD): 3V to 15V
- Input Voltage (V_IN): 0V to V_DD
- Output Voltage (V_OUT): 0V to V_DD
- Input Current (I_IN): ±1 µA (max)
- Output Current (I_OUT): 25 mA (max per output)
- Propagation Delay (t_PD): Typically 100 ns at V_DD = 5V
- Operating Temperature Range: -55°C to 125°C
- Package Types: Available in various packages, including DIP (Dual In-line Package) and SOIC (Small Outline Integrated Circuit).
## Pin Configuration
The CD40147BE typically has 16 pins, with the following key pin functions:
- Pins 1-4: BCD inputs (A, B, C, D)
- Pin 5: Latch Enable (LE)
- Pin 6: Blanking (BL)
- Pin 7: Test (T)
- Pins 8-14: Outputs (a, b, c, d, e, f, g) for the 7-segment display
- Pin 15: Ground (GND)
- Pin 16: V_DD (Power Supply)
## Application Circuit
In typical applications, the CD40147BE is connected to a 7-segment display, with the BCD inputs connected to a binary counter or other digital logic that provides the BCD representation of the desired decimal number. The latch enable pin can be used to hold the output stable while the input changes, and the blanking pin can be used to turn off the display when needed.
## Conclusion
The Texas Instruments CD40147BE is a versatile and efficient BCD to 7-segment decoder/driver that is widely used in digital display applications. Its combination of low power consumption, wide operating voltage range, and ease of use makes it an excellent choice for designers looking to implement numerical displays in their electronic projects.
