Overview
The MC74HC138ADTR2G, produced by onsemi, is a high-performance silicon-gate CMOS 1-of-8 decoder/demultiplexer. This device is identical in pinout to the LS138 and is designed to decode a three-bit address to one of eight active-low outputs. It features three chip select inputs, two active-low and one active-high, which facilitate demultiplexing, cascading, and chip-selecting functions. The MC74HC138ADTR2G is compatible with standard CMOS outputs and, with pull-up resistors, can also interface with LSTTL outputs. This component is particularly useful in applications requiring the conversion of a binary code to a one-out-of-many signal.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| DC Supply Voltage (VCC) | 2.0 to 6.0 | V |
| Operating Temperature Range | -55 to +125 | °C |
| Minimum High-Level Input Voltage (VIH) | 1.5 to 4.2 | V |
| Maximum Low-Level Input Voltage (VIL) | 0.5 to 1.8 | V |
| Maximum Input Leakage Current | ±1.0 | μA |
| Output Drive Capability | 10 LSTTL Loads | |
| Maximum Propagation Delay (tPLH, tPHL) | 23 to 205 ns | ns |
| Power Dissipation in Still Air | 450 mW (TSSOP Package) | mW |
| Storage Temperature | -65 to +150 | °C |
Key Features
- Decodes a three-bit address to one of eight active-low outputs.
- Three chip select inputs: two active-low and one active-high.
- Compatible with standard CMOS outputs and LSTTL outputs with pull-up resistors.
- Output drive capability of 10 LSTTL loads.
- Operating voltage range: 2.0 to 6.0 V.
- Low input current: 1.0 μA.
- High noise immunity characteristic of CMOS devices.
- In compliance with JEDEC Standard No. 7A.
Applications
- Digital decoding and demultiplexing in various electronic systems.
- Cascading and chip-selecting functions in complex digital circuits.
- Level conversion for interfacing TTL or NMOS outputs to high-speed CMOS inputs.
- Use in microprocessor and microcontroller systems for address decoding.
- Applications requiring the conversion of a binary code to a one-out-of-many signal.
Q & A
- What is the primary function of the MC74HC138ADTR2G?
The primary function is to decode a three-bit address to one of eight active-low outputs.
- What are the operating voltage ranges for the MC74HC138ADTR2G?
The operating voltage range is from 2.0 to 6.0 V.
- How many chip select inputs does the MC74HC138ADTR2G have?
The device has three chip select inputs: two active-low and one active-high.
- What is the output drive capability of the MC74HC138ADTR2G?
The output drive capability is 10 LSTTL loads.
- Is the MC74HC138ADTR2G compatible with LSTTL outputs?
Yes, it is compatible with LSTTL outputs when using pull-up resistors.
- What is the maximum propagation delay for the MC74HC138ADTR2G?
The maximum propagation delay ranges from 23 to 205 ns depending on the operating conditions.
- What are the storage temperature limits for the MC74HC138ADTR2G?
The storage temperature range is from -65 to +150 °C.
- What is the power dissipation in still air for the TSSOP package?
The power dissipation in still air for the TSSOP package is 450 mW.
- Is the MC74HC138ADTR2G compliant with any specific standards?
Yes, it is in compliance with JEDEC Standard No. 7A.
- What are some common applications of the MC74HC138ADTR2G?
Common applications include digital decoding and demultiplexing, cascading and chip-selecting functions, and level conversion in various electronic systems.
