Overview
The SN74LS247NS is a BCD-to-seven-segment decoder/driver produced by Texas Instruments. This component is part of the 74LS series and is designed to convert Binary Coded Decimal (BCD) inputs into seven-segment display outputs. It is electrically and functionally identical to the SN54LS47 and SN74LS47, offering compatibility and flexibility in design choices. The SN74LS247NS features active-low outputs, making it suitable for driving indicators directly without the need for external resistors.
Key Specifications
| Parameter | Value |
|---|---|
| Package Type | SOIC (NS) |
| Pins | 16 |
| Operating Temperature Range | 0°C to 70°C |
| Supply Voltage | 4.75V to 5.25V |
| Input Current | -0.4mA to 1.6mA |
| Output Current | -0.4mA to 8mA |
| Propagation Delay Time | Approx. 25ns |
| RoHS Compliance | Yes |
Key Features
- BCD-to-seven-segment decoder/driver functionality
- Active-low outputs for direct drive of indicators
- Lamp-test provision and leading/trailing zero suppression
- Internal pull-ups eliminate the need for external resistors
- Lamp intensity modulation capability
- Full ripple-blanking input/output controls
- Overriding blanking input for lamp intensity control or output inhibition
Applications
The SN74LS247NS is widely used in digital display systems, such as LED displays, LCD displays, and other types of seven-segment displays. It is particularly useful in applications requiring BCD input conversion to seven-segment output, including digital clocks, calculators, and other electronic devices that require numerical display. Additionally, it can be used in industrial control systems and automotive electronics where numerical displays are necessary.
Q & A
- What is the primary function of the SN74LS247NS?
The primary function is to convert BCD inputs into seven-segment display outputs. - What type of outputs does the SN74LS247NS have?
The SN74LS247NS has active-low outputs. - What is the operating temperature range of the SN74LS247NS?
The operating temperature range is from 0°C to 70°C. - Does the SN74LS247NS require external resistors for its outputs?
No, it has internal pull-ups that eliminate the need for external resistors. - What is the purpose of the lamp-test provision in the SN74LS247NS?
The lamp-test provision allows for testing the lamps at any time when the BI/RBO node is at a high level. - Is the SN74LS247NS RoHS compliant?
Yes, it is RoHS compliant. - What is the typical propagation delay time of the SN74LS247NS?
The typical propagation delay time is approximately 25ns. - Can the SN74LS247NS be used interchangeably with other similar devices?
Yes, it is electrically and functionally identical to the SN54LS47 and SN74LS47, making it interchangeable in designs. - What types of displays can the SN74LS247NS drive?
The SN74LS247NS can drive LED, LCD, and other types of seven-segment displays. - What are some common applications of the SN74LS247NS?
Common applications include digital clocks, calculators, industrial control systems, and automotive electronics.
