Quadruple 2-Line To 1-Line Data Selectors/Multiplexers With 3-State Outputs The SN74HCT257D is a quad 2-line to 1-line data selector/multiplexer manufactured by Texas Instruments (TI).
### **Specifications:**
- **Logic Type:** Data Selector/Multiplexer
- **Number of Channels:** 4
- **Input Lines per Channel:** 2
- **Output Lines per Channel:** 1
- **Supply Voltage Range (VCC):** 4.5V to 5.5V
- **High-Level Input Voltage (VIH):** 2V (min)
- **Low-Level Input Voltage (VIL):** 0.8V (max)
- **High-Level Output Current (IOH):** -6mA
- **Low-Level Output Current (IOL):** 6mA
- **Propagation Delay Time (tpd):** 17ns (typ) at 5V
- **Operating Temperature Range:** -40°C to +85°C
- **Package Type:** SOIC-16
### **Descriptions:**
The SN74HCT257D is a high-speed CMOS logic device that selects one of two data inputs (A or B) based on the select (S) input. It features non-inverting outputs and three-state capability, allowing multiple devices to share a common bus.
### **Features:**
- **3-State Outputs:** Enable/disable functionality for bus-oriented applications
- **Common Select Input:** Single select line controls all four multiplexers
- **Balanced Propagation Delays:** Ensures consistent performance
- **Low Power Consumption:** CMOS technology reduces power dissipation
- **Wide Operating Voltage:** Compatible with TTL levels (5V operation)
- **High Noise Immunity:** Typical of HCT family devices
This device is commonly used in digital systems for data routing, signal switching, and bus interfacing.
