Overview
The SN74LVC138A, produced by Texas Instruments, is a 3-line to 8-line decoder/demultiplexer designed for high-performance memory-decoding or data-routing applications. This device is optimized for very short propagation delay times, making it ideal for use in high-speed memory systems. It minimizes the effects of system decoding and can be used in conjunction with fast enable circuits to ensure that the overall system delay remains negligible.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Supply Voltage Range | 1.65 | - | 3.6 | V |
| Input Voltage Range | -0.5 | - | 6.5 | V |
| Output Voltage Range | -0.5 | - | VCC + 0.5 | V |
| Propagation Delay Time (tpd) | - | - | 5.8 ns at 3.3 V | ns |
| Output Ground Bounce (VOLP) | - | < 0.8 V at VCC = 3.3 V, TA = 25°C | - | V |
| Output VOH Undershoot (VOHV) | - | > 2 V at VCC = 3.3 V, TA = 25°C | - | V |
| Operating Temperature Range | -40 | - | 125 | °C |
| Package Type | - | - | TSSOP (PW) | - |
| Pins | - | - | 16 | - |
Key Features
- Operates from 1.65 V to 3.6 V.
- Inputs accept voltages up to 5.5 V.
- Maximum propagation delay time of 5.8 ns at 3.3 V.
- Typical output ground bounce (VOLP) < 0.8 V at VCC = 3.3 V, TA = 25°C.
- Typical output VOH undershoot (VOHV) > 2 V at VCC = 3.3 V, TA = 25°C.
- Latch-up performance exceeds 250 mA per JESD 17.
- ESD protection exceeds 2000 V per MIL-STD-883, Method 3015, and 200 V using the Machine Model.
- Schmitt-trigger action at all inputs for tolerance of slower input rise and fall times.
- Multiple enable inputs for easy expansion and demultiplexing capability.
- Direct interface with TTL levels and compatibility in mixed 3.3 V and 5 V environments.
Applications
- High-performance memory-decoding applications.
- Data-routing applications requiring short propagation delay times.
- Demultiplexing applications using one of the active-low enable inputs as the data input and the remaining enable inputs as strobes.
- Memory chip select decoding.
- Mixed 3.3 V and 5 V system environments as a translator.
Q & A
- What is the primary function of the SN74LVC138A?
The SN74LVC138A is a 3-line to 8-line decoder/demultiplexer designed for high-performance memory-decoding or data-routing applications.
- What is the operating voltage range of the SN74LVC138A?
The device operates from 1.65 V to 3.6 V.
- What is the maximum propagation delay time of the SN74LVC138A at 3.3 V?
The maximum propagation delay time is 5.8 ns at 3.3 V.
- What is the input voltage tolerance of the SN74LVC138A?
The inputs can accept voltages up to 5.5 V.
- What type of ESD protection does the SN74LVC138A have?
The device has ESD protection exceeding 2000 V per MIL-STD-883, Method 3015, and 200 V using the Machine Model.
- Can the SN74LVC138A be used in mixed voltage systems?
Yes, it can be used as a translator in mixed 3.3 V and 5 V system environments.
- What is the operating temperature range of the SN74LVC138A?
The device operates from -40°C to 125°C.
- How many enable inputs does the SN74LVC138A have?
The device has three enable inputs: two active-low and one active-high.
- Can the SN74LVC138A be used for demultiplexing applications?
Yes, it can be used as an eight-output demultiplexer by using one of the active-low enable inputs as the data input and the remaining enable inputs as strobes.
- What type of package is available for the SN74LVC138A?
The device is available in TSSOP (PW) package.
