Overview
The 74HCT138PW,118 is a 3-to-8 line decoder/demultiplexer integrated circuit produced by NXP Semiconductors. This device is part of the 74HCT family, which operates at TTL (Transistor-Transistor Logic) levels. It decodes three binary weighted address inputs (A0, A1, and A2) to eight mutually exclusive outputs (Y0 to Y7). The IC features three enable inputs (E1, E2, and E3), allowing for flexible control over the output states. This component is widely used in various electronic systems for decoding and demultiplexing applications.
Key Specifications
| Type number | VCC (V) | Logic switching levels | Output drive capability (mA) | tpd (ns) | Power dissipation considerations | Tamb (°C) | Rth(j-a) (K/W) | Ψth(j-top) (K/W) | Rth(j-c) (K/W) | Package name |
|---|---|---|---|---|---|---|---|---|---|---|
| 74HCT138PW | 4.5 - 5.5 | TTL | ± 4 | 19 | low | -40 to +125 | 125 | 4.7 | 55.5 | TSSOP16 |
Key Features
- Decoding and Demultiplexing: Decodes three binary weighted address inputs to eight mutually exclusive outputs.
- Enable Inputs: Features three enable inputs (E1, E2, and E3) for flexible control over output states.
- Wide Supply Voltage Range: Operates from 4.5 to 5.5 V.
- Low Power Dissipation: CMOS low power dissipation.
- High Noise Immunity: High noise immunity and latch-up performance exceeding 100 mA per JESD 78 Class II Level B.
- ESD Protection: ESD protection with HBM exceeding 2000 V and CDM exceeding 1000 V.
- Multiple Package Options: Available in TSSOP16 package.
- Temperature Range: Specified from -40 °C to +125 °C.
Applications
- Memory Chip Select Decoding: Ideal for memory chip select decoding in various memory systems.
- Demultiplexing: 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.
- Parallel Expansion: Allows easy parallel expansion to a 1-of-32 (5 to 32 lines) decoder with just four '138 ICs and one inverter.
- General Digital Systems: Used in various digital systems requiring decoding and demultiplexing functions.
Q & A
- What is the primary function of the 74HCT138PW,118 IC?
The primary function is to decode three binary weighted address inputs to eight mutually exclusive outputs and to act as a demultiplexer.
- What are the logic switching levels for the 74HCT138PW,118?
The logic switching levels are TTL (Transistor-Transistor Logic).
- What is the supply voltage range for the 74HCT138PW,118?
The supply voltage range is from 4.5 to 5.5 V.
- What is the output drive capability of the 74HCT138PW,118?
The output drive capability is ± 4 mA.
- What is the typical propagation delay (tpd) for the 74HCT138PW,118?
The typical propagation delay is 19 ns.
- What kind of ESD protection does the 74HCT138PW,118 have?
The device has ESD protection with HBM exceeding 2000 V and CDM exceeding 1000 V.
- What is the operating temperature range for the 74HCT138PW,118?
The operating temperature range is from -40 °C to +125 °C.
- What package type is the 74HCT138PW,118 available in?
The device is available in a TSSOP16 package.
- Can the 74HCT138PW,118 be used for parallel expansion?
Yes, it can be used for parallel expansion to a 1-of-32 (5 to 32 lines) decoder with just four '138 ICs and one inverter.
- What are some common applications of the 74HCT138PW,118?
Common applications include memory chip select decoding, demultiplexing, and general digital systems requiring decoding and demultiplexing functions.
