Overview
The MC74ACT138DG, produced by onsemi, is a high-speed 1-of-8 decoder/demultiplexer. This device is ideally suited for high-speed bipolar memory chip select address decoding. It features multiple input enables, allowing for easy parallel expansion to higher-order decoders, such as a 1-of-24 decoder using three devices or a 1-of-32 decoder using four devices and one inverter.
Key Specifications
| Attribute | Value |
|---|---|
| Logic Circuit | Decoder/Demux |
| Family | ACT/Q |
| No of Functions / Channels | 2 |
| Supply Voltage-Nom | 2V to 6V |
| Package Style | SOIC-16 |
| Mounting Method | Surface Mount |
| VCC Min (V) | 4.5 |
| VCC Max (V) | 5.5 |
| Propagation Delay Max (ns) | 10.5 |
| Output Current Max (mA) | 24 |
Key Features
- Demultiplexing Capability
- Multiple Input Enable for Easy Expansion
- Active LOW Mutually Exclusive Outputs
- Outputs Source/Sink 24 mA
- ACT138 Has TTL Compatible Inputs
- Available in Pb-free package(s)
Applications
The MC74ACT138DG is primarily used in high-speed bipolar memory chip select address decoding. It can also be used as an 8-output demultiplexer by utilizing one of the active LOW Enable inputs as the data input and the other Enable inputs as strobes. Additionally, it can be expanded to create higher-order decoders such as 1-of-24 or 1-of-32 decoders with minimal additional components.
Q & A
- What is the primary function of the MC74ACT138DG?
The MC74ACT138DG is a high-speed 1-of-8 decoder/demultiplexer. - What are the supply voltage ranges for the MC74ACT138DG?
The supply voltage range is 2V to 6V. - What package styles are available for the MC74ACT138DG?
The device is available in SOIC-16 and other package styles such as TSSOP-16. - How can the MC74ACT138DG be expanded for higher-order decoding?
It can be expanded to a 1-of-24 decoder using three devices or a 1-of-32 decoder using four devices and one inverter. - What is the maximum output current of the MC74ACT138DG?
The outputs can source/sink up to 24 mA. - Are the inputs of the MC74ACT138DG TTL compatible?
Yes, the ACT138 has TTL compatible inputs. - Is the MC74ACT138DG available in Pb-free packages?
Yes, the device is available in Pb-free package(s). - What is the typical propagation delay of the MC74ACT138DG?
The typical propagation delay is up to 10.5 ns. - How many enable inputs does the MC74ACT138DG have?
The device has three enable inputs: two active-LOW and one active-HIGH. - What is the mounting method for the MC74ACT138DG?
The device uses surface mount technology.
