The 74LS series of integrated circuits (ICs) was one of the most popular logic families of transistor-transistor logic (TTL) logic chips. 74LS series is a bipolar, low-power Schottky IC. The 74LS247 is a BCD-to-Seven-Segment Decoder/Drivers. The 74LS247 composes 6 and 9 with the tails and is active for low outputs for direct drive of indicators.
74LS247 Features
- Full BCD to Seven Segment Decoder
- Open Collector Outputs to Drive Indicators Directly
- Lamp Test Provision
- Leading/Training Zero Suppression
- Standard TTL Switching Voltages
74LS247 Specifications
| Supply Voltage | 4.75 – 5.25Vdc |
| Maximum Clock Frequency | 40Mhz |
| Power Dissipation | 2mW/gate @100kHz |
| Minimum Output Current | 8mA |
| Propagation Delay | 10nS |
| Fan Out (TTL Loads) | 20 |
74LS247 Pinout Diagram
74LS247 Pin Description
| Pin No | Pin Name | Description |
| 1 | B | Input Pin |
| 2 | C | Input Pin |
| 3 | LAMP TEST | Lamp test Pin |
| 4 | RB OUT | Ripple Blanking Output |
| 5 | RB IN | Ripple Blanking Input |
| 6 | D | Input Pin |
| 7 | A | Input Pin |
| 8 | GND | Ground |
| 9 | e | Output |
| 10 | d | Output |
| 11 | c | Output |
| 12 | b | Output |
| 13 | a | Output |
| 14 | g | Output |
| 15 | f | Output |
| 16 | VCC | Positive Supply |
Applications
- Decoders are used to input data to a specified output line as is done in addressing core memory where input data is to be stored in a specified memory location.
- It is used in code conversions.
- In high-performance memory systems, this decoder can be used to minimize the effects of system decoding.
74LS247 Alternative Equivalent
74LS248
Download 74LS247 BCD to 7-Segment Decoder/Driver Datasheet from the link given below.
