The 74LS42 is a Multipurpose Decoder designed to accept four BCD inputs and provide ten mutually exclusive outputs. It is a member of the 74XXYY IC series. The 74LS42 is fabricated with the Schottky barrier diode process for high speed. The 74LS42 IC has a wide range of working voltage, a wide range of working conditions, and directly interfaces with CMOS, NMOS, and TTL. The output of the IC always comes in TTL which makes it easy to work with other TTL devices and microcontrollers.
What is a Binary Decoder?
A Binary Decoder converts coded inputs into coded outputs, where the input and output codes are different and decoders are available to “decode” either a Binary or BCD (8421 code) input pattern to typically a Decimal output code. A decoder’s output code usually has more bits than its input code, practical “binary decoder” circuits include 2-to-4, 3-to-8, and 4-to-16 line configurations.
74LS42 Pinout
74LS42 Pin Configuration
| Pin No | Pin Name | Description |
|---|---|---|
| 1 | Q0 | Output Q0 |
| 2 | Q1 | Output Q1 |
| 3 | Q2 | Output Q2 |
| 4 | Q3 | Output Q3 |
| 5 | Q4 | Output Q4 |
| 6 | Q5 | Output Q5 |
| 7 | Q6 | Output Q6 |
| 8 | GND | Ground Pin |
| 9 | Q7 | Output Q7 |
| 10 | Q8 | Output Q8 |
| 11 | Q9 | Output Q9 |
| 12 | A3 (8) | Input D |
| 13 | A2 (4) | Input C |
| 14 | A1 (2) | Input B |
| 15 | A0 (1) | Input A |
| 16 | VCC | Supply Voltage |
74LS42 Features & Specifications
- Function: Decoder, Demultiplexer
- Technology Family: LS
- VCC (Min): 4.75V
- VCC (Max): 5.25V
- No. of Channels: 1
- Voltage (Nom): 5V
- Configuration: 4:10
- Type: Standard
- IOL (Max): 8mA
- IOH (Max): -0.4mA
- Rating: Catalog
- Operating temperature range: 0°C to 70°C
- Bits (#): 10
- Digital input leakage (Max): 5uA
- ESD CDM: 0.75KV
- ESD HBM: 2KV
Applications
- The chip provides TTL outputs that are needed in some systems.
- This performs DEMUX function in various devices such as RAM, ROM & various other memory storage devices
You can download this Datasheet for 74LS42 Binary decoder from the link given below:
See Also: 74LS20 Dual 4 – Input NAND IC | 74LS10 Triple 3-Input NAND IC | 74LS08 Quadruple Two Input AND Gate IC
