Overview
The SN74ALS138AD is a 3-line to 8-line decoder/demultiplexer produced by Texas Instruments. This device is designed for high-performance memory-decoding or data-routing applications, particularly in systems requiring very short propagation delay times. It is part of the ALS (Advanced Low-power Schottky) family, known for its high speed and low power consumption. The SN74ALS138AD is suitable for use in high-speed memory systems and data transmission systems where minimal system decoding delays are crucial.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Logic IC Type | OTHER DECODER/DRIVER | |
| Sub Category | Decoder/Drivers | |
| Family | ALS | |
| Number of Terminals | 16 | |
| Operating Temperature-Min | 0 | °C |
| Operating Temperature-Max | 70 | °C |
| Output Polarity | INVERTED | |
| Package Code | SOP16 | |
| Supply Voltage-Nom (Vsup) | 5 | V |
| Supply Voltage-Min (Vsup) | 4.5 | V |
| Supply Voltage-Max (Vsup) | 5.5 | V |
| Propagation Delay (tpd) | 18.0 ns | |
| Power Supply Current-Max (ICC) | 10.0 mA |
Key Features
- Designed specifically for high-speed memory decoders and data transmission systems.
- Incorporate three enable inputs (G1, G2A, and G2B) to simplify cascading and/or data reception.
- Two active-low and one active-high enable inputs reduce the need for external gates or inverters when expanding.
- Package options include plastic small-outline (D) packages, ceramic chip carriers (FK), and standard plastic (N) and ceramic (J) 300-mil DIPs.
- An enable input can be used as a data input for demultiplexing applications.
- Minimal system delay introduced by the Schottky-clamped system decoder.
Applications
- High-performance memory-decoding applications.
- Data-routing applications requiring very short propagation delay times.
- High-speed memory systems with fast enable circuits.
- Demultiplexing applications where an enable input can be used as a data input.
- Cascading decoders to implement larger decoding systems (e.g., 24-line or 32-line decoders).
Q & A
- What is the primary function of the SN74ALS138AD?
The SN74ALS138AD is a 3-line to 8-line decoder/demultiplexer designed for high-performance memory-decoding or data-routing applications.
- What are the operating temperature ranges for the SN74ALS138AD?
The SN74ALS138AD operates from 0°C to 70°C.
- What are the supply voltage specifications for the SN74ALS138AD?
The supply voltage for the SN74ALS138AD is 4.5 V to 5.5 V, with a nominal voltage of 5 V.
- How many enable inputs does the SN74ALS138AD have?
The SN74ALS138AD has three enable inputs: two active-low (G2A, G2B) and one active-high (G1).
- What is the propagation delay of the SN74ALS138AD?
The propagation delay (tpd) of the SN74ALS138AD is 18.0 ns.
- Can the SN74ALS138AD be used in demultiplexing applications?
- What package options are available for the SN74ALS138AD?
The SN74ALS138AD is available in plastic small-outline (D) packages, ceramic chip carriers (FK), and standard plastic (N) and ceramic (J) 300-mil DIPs.
- How does the SN74ALS138AD minimize system decoding delays?
The SN74ALS138AD minimizes system decoding delays due to its Schottky-clamped system decoder, which introduces negligible delay times.
- Can the SN74ALS138AD be used to implement larger decoding systems?
- What is the maximum power supply current for the SN74ALS138AD?
The maximum power supply current (ICC) for the SN74ALS138AD is 10.0 mA.
- What package options are available for the SN74ALS138AD?
