Overview
The SN74LS247N is a BCD-to-Seven-Segment Decoder/Driver produced by Texas Instruments. This component is part of the LS series and is designed to convert Binary Coded Decimal (BCD) inputs into seven-segment display outputs. It is electrically and functionally identical to the SN5447A/SN7447A and has the same pin assignments as its equivalents. The SN74LS247N features active-low outputs, making it suitable for direct drive of indicators.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Package Type | PDIP (N) | - |
| Number of Pins | 16 | - |
| Operating Temperature Range | 0 to 70 | °C |
| Supply Voltage (Nominal) | 5 | V |
| Supply Voltage (Min/Max) | 4.75 / 5.25 | V |
| Output Characteristics | Open-Collector | - |
| Output Polarity | Inverted | - |
| Propagation Delay (tpd) | 100 ns | - |
| Power Supply Current (Max) | 10 mA | - |
| Load Capacitance (CL) | 15 pF | - |
| Terminal Finish | Nickel Palladium Gold | - |
| Terminal Form | Through-Hole | - |
| Terminal Pitch | 2.54 mm | - |
Key Features
- Open-Collector Outputs: Drive indicators directly without the need for external resistors.
- Lamp-Test Provision: Allows for lamp testing at any time when the BI/RBO node is at a high level.
- Leading/Trailing Zero Suppression: Automatic leading and/or trailing-edge zero-blanking control (RBI and RBO).
- Lamp Intensity Modulation: Overriding blanking input (BI) can be used to control lamp intensity by pulsing or to inhibit the outputs.
- Full Ripple-Blanking Input/Output Controls: Ensures proper display and control of the seven-segment display.
- Compatibility with TTL Logic Outputs: Inputs and outputs are entirely compatible for use with TTL logic outputs.
Applications
The SN74LS247N is widely used in various digital display systems, including:
- Seven-segment display drivers in digital clocks, calculators, and other electronic devices.
- BCD-to-seven-segment conversion in industrial control panels and instrumentation.
- Display systems in automotive and consumer electronics.
- Any application requiring the conversion of BCD inputs to seven-segment display outputs.
Q & A
- What is the primary function of the SN74LS247N?
The primary function of the SN74LS247N is to convert Binary Coded Decimal (BCD) inputs into seven-segment display outputs.
- What type of outputs does the SN74LS247N have?
The SN74LS247N has active-low, open-collector outputs.
- What is the operating temperature range of the SN74LS247N?
The operating temperature range is from 0°C to 70°C.
- What is the supply voltage range for the SN74LS247N?
The supply voltage range is from 4.75V to 5.25V, with a nominal voltage of 5V.
- Does the SN74LS247N support lamp testing?
Yes, it has a lamp-test provision that allows for lamp testing at any time when the BI/RBO node is at a high level.
- What is the propagation delay of the SN74LS247N?
The propagation delay (tpd) is 100 ns.
- Is the SN74LS247N compatible with TTL logic outputs?
Yes, inputs and outputs are entirely compatible for use with TTL logic outputs.
- What is the purpose of the RBI and RBO controls in the SN74LS247N?
The RBI and RBO controls provide automatic leading and/or trailing-edge zero-blanking control.
- How can the lamp intensity be controlled in the SN74LS247N?
The lamp intensity can be controlled by using the overriding blanking input (BI) to pulse or inhibit the outputs.
- What type of packaging is available for the SN74LS247N?
The SN74LS247N is available in a 16-pin PDIP (N) package.
