Overview
The 74HC138DB112, produced by NXP USA Inc., is a 1-of-8 decoder/demultiplexer integrated circuit. This device is part of the 74HC series, known for its high-performance silicon-gate CMOS technology. It is designed to decode three binary weighted address inputs (A0, A1, and A2) to eight mutually exclusive outputs (Y0 to Y7), making it highly versatile in various digital circuit applications.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Supply Voltage (VCC) | 2.0 | 5.0 | 6.0 | V |
| Input Voltage (VI) | 0 | - | VCC | V |
| Output Voltage (VO) | 0 | - | VCC | V |
| Ambient Temperature (Tamb) | -40 | 25 | 125 | °C |
| Input Transition Rise and Fall Rate (Δt/ΔV) | - | 1.67 (at VCC=4.5V) | 139 (at VCC=4.5V) | ns/V |
| Propagation Delay (An to Yn) | - | 15 (at VCC=4.5V) | 30 (at VCC=4.5V) | ns |
Key Features
- Decodes three binary weighted address inputs to eight mutually exclusive outputs.
- Features three enable inputs (E1, E2, and E3) for easy expansion and demultiplexing capabilities.
- Wide supply voltage range from 2.0 to 6.0 V.
- CMOS low power dissipation and high noise immunity.
- Active LOW mutually exclusive outputs.
- Complies with JEDEC standards (JESD8C and JESD7A).
- ESD protection (HBM JESD22-A114F exceeds 2000 V and MM JESD22-A115-A exceeds 200 V).
Applications
The 74HC138DB112 is ideal for various digital circuit applications, including:
- Memory chip select decoding.
- Demultiplexing functions by using one of the active LOW enable inputs as the data input and the remaining enable inputs as strobes.
- Cascading and chip-selecting functions in larger digital systems.
- General-purpose decoding and demultiplexing in industrial, automotive, and IoT devices.
Q & A
- What is the primary function of the 74HC138DB112?
The primary function is to decode three binary weighted address inputs to eight mutually exclusive outputs and to act as a demultiplexer. - What is the supply voltage range for the 74HC138DB112?
The supply voltage range is from 2.0 to 6.0 V. - How many enable inputs does the 74HC138DB112 have?
The device has three enable inputs (E1, E2, and E3). - What are the output characteristics of the 74HC138DB112?
The outputs are active LOW and mutually exclusive. - Is the 74HC138DB112 compatible with TTL inputs?
Yes, with pull-up resistors, the inputs are compatible with LSTTL outputs. - What is the propagation delay of the 74HC138DB112?
The propagation delay is approximately 15 ns at VCC = 4.5 V. - Does the 74HC138DB112 have ESD protection?
Yes, it exceeds 2000 V for HBM and 200 V for MM. - What are the temperature operating ranges for the 74HC138DB112?
The ambient temperature range is from -40°C to +125°C. - Can the 74HC138DB112 be used for cascading and chip-selecting functions?
Yes, it is designed to facilitate these functions. - Is the 74HC138DB112 compliant with JEDEC standards?
Yes, it complies with JESD8C and JESD7A standards).
