Overview
The SN74HC257NSR is a quad 2-line to 1-line data selector/multiplexer integrated circuit produced by Texas Instruments. This device is part of the HC (High-Speed CMOS) logic family and is designed to multiplex signals from 4-bit data sources to 4-output data lines in bus-organized systems. It operates over a wide voltage range of 2 V to 6 V, making it versatile for various applications.
Key Specifications
| Parameter | Unit | Min | Typ | Max |
|---|---|---|---|---|
| Supply Voltage (VCC) | V | 2 | 5 | 6 |
| High-Level Input Voltage (VIH) | V | 1.5 (VCC=2V), 3.15 (VCC=4.5V), 4.2 (VCC=6V) | ||
| Low-Level Input Voltage (VIL) | V | 0.3 (VCC=2V), 0.9 (VCC=4.5V), 1.2 (VCC=6V) | ||
| Operating Free-Air Temperature (TA) | °C | -40 | 85 | |
| Propagation Delay Time (tpd) | ns | 9 (VCC=6V) | 17 (VCC=6V) | 25 (VCC=6V) |
| Output Enable Time (ten) | ns | 13 (VCC=6V) | 26 (VCC=6V) | 38 (VCC=6V) |
| Output Disable Time (tdis) | ns | 13 (VCC=6V) | 26 (VCC=6V) | 38 (VCC=6V) |
| Input Transition Rise/Fall Time | ns | 400 (VCC=6V) | ||
| Storage Temperature Range (Tstg) | °C | -65 | 150 |
Key Features
- Wide operating voltage range of 2 V to 6 V.
- High-current inverting outputs drive up to 15 LSTTL loads.
- Low power consumption, with a maximum ICC of 80 µA.
- Typical propagation delay time of 9 ns at VCC = 6 V.
- ±6-mA output drive at 5 V.
- Low input current of 1 µA max.
- Provides bus interface from multiple sources in high-performance systems.
- 3-state outputs do not load the data lines when the output-enable (G) input is at a high logic level.
Applications
The SN74HC257NSR is suitable for a variety of applications, including:
- Bus-organized systems where multiple data sources need to be multiplexed.
- High-performance digital systems requiring low power consumption and fast switching times.
- Embedded systems and microcontrollers where data needs to be selectively routed.
- Industrial control systems and automation where reliable and efficient data handling is crucial.
Q & A
- What is the operating voltage range of the SN74HC257NSR?
The operating voltage range is from 2 V to 6 V.
- What is the typical propagation delay time of the SN74HC257NSR at 6 V?
The typical propagation delay time is 9 ns.
- How many LSTTL loads can the outputs of the SN74HC257NSR drive?
The outputs can drive up to 15 LSTTL loads.
- What is the maximum input current of the SN74HC257NSR?
The maximum input current is 1 µA.
- What is the purpose of the output-enable (G) input in the SN74HC257NSR?
The output-enable (G) input controls the 3-state outputs, ensuring they do not load the data lines when at a high logic level.
- What is the storage temperature range for the SN74HC257NSR?
The storage temperature range is from -65°C to 150°C.
- What are the package options available for the SN74HC257NSR?
The SN74HC257NSR is available in SOP (NS) package.
- Is the SN74HC257NSR RoHS compliant?
Yes, the SN74HC257NSR is RoHS compliant.
- What is the maximum operating free-air temperature for the SN74HC257NSR?
The maximum operating free-air temperature is 85°C.
- How many data lines can the SN74HC257NSR multiplex from 4-bit data sources?
The device can multiplex signals from 4-bit data sources to 4-output data lines.
