Overview
The SN74HC138NG4, produced by Texas Instruments, is a 3-line to 8-line decoder/demultiplexer integrated circuit. This device is specifically designed for high-performance memory-decoding and data-routing applications, requiring very short propagation delay times. It features three binary inputs (A, B, and C) that select one of eight output lines, and three enable inputs (two active-low and one active-high) to simplify cascading or data reception.
Key Specifications
| Parameter | Min | Nom | Max | Unit |
|---|---|---|---|---|
| VCC Supply Voltage | 2 | 5 | 6 | V |
| VIH High-Level Input Voltage (VCC = 2 V) | - | - | 1.5 | V |
| VIH High-Level Input Voltage (VCC = 4.5 V) | - | - | 3.15 | V |
| VIH High-Level Input Voltage (VCC = 6 V) | - | - | 4.2 | V |
| VIL Low-Level Input Voltage (VCC = 2 V) | 0.5 | - | - | V |
| VIL Low-Level Input Voltage (VCC = 4.5 V) | 1.35 | - | - | V |
| VIL Low-Level Input Voltage (VCC = 6 V) | 1.8 | - | - | V |
| IO Continuous Output Current | - | - | ±25 | mA |
| TJ Junction Temperature | - | - | 150 | °C |
| tpd Propagation Delay Time | - | 15 | - | ns |
Key Features
- Wide operating voltage range (2 V to 6 V)
- Outputs can drive up to 10 LSTTL loads
- Low power consumption, 80-µA maximum ICC
- Typical propagation delay time (tpd) of 15 ns
- ±4-mA output drive at 5 V
- Low input current of 1-µA maximum
- Active low outputs (selected output is low)
- Incorporate three enable inputs to simplify cascading or data reception
Applications
- LED displays
- Servers
- White goods
- Power infrastructure
- Building automation
- Factory automation
Q & A
- What is the primary function of the SN74HC138NG4? The SN74HC138NG4 is a 3-line to 8-line decoder/demultiplexer, designed for high-performance memory-decoding and data-routing applications.
- What is the operating voltage range of the SN74HC138NG4? The operating voltage range is from 2 V to 6 V.
- How many LSTTL loads can the outputs of the SN74HC138NG4 drive? The outputs can drive up to 10 LSTTL loads.
- What is the typical propagation delay time of the SN74HC138NG4? The typical propagation delay time (tpd) is 15 ns.
- What are the types of enable inputs available on the SN74HC138NG4? There are two active-low and one active-high enable inputs.
- Can the SN74HC138NG4 be used in automotive applications? Yes, the SN74HC138-Q1 version is qualified for automotive applications and has ESD protection exceeding 2000 V per MIL-STD-883, Method 3015.
- How does the SN74HC138NG4 simplify cascading or data reception? The device incorporates three enable inputs to simplify cascading or data reception, reducing the need for external gates or inverters.
- What are some common applications of the SN74HC138NG4? Common applications include LED displays, servers, white goods, power infrastructure, building automation, and factory automation.
- What is the maximum junction temperature for the SN74HC138NG4? The maximum junction temperature is 150°C.
- How much current can the outputs of the SN74HC138NG4 continuously handle? The outputs can continuously handle up to ±25 mA.
