SN74HC148N

Overview

The SN74HC148N is an 8-line to 3-line priority encoder manufactured by Texas Instruments. It operates within a supply voltage range of 2V to 6V and supports a recommended operating temperature from -40°C to +85°C. The device features active-low data inputs and outputs, with propagation delays typically ranging from 16ns to 45ns depending on voltage. It provides output drive capabilities for up to 10 LSTTL loads and includes enable input (EI) and enable output (EO) signals for cascading multiple stages without external circuitry.

Feature Summary

• Encodes eight active-low data lines into three active-low binary outputs while prioritizing the highest-order input.
• Includes dedicated enable input and enable output pins to facilitate cascading multiple units for expanded encoding capacity.
• Supports direct driving of standard logic loads with low power consumption characteristics.

Applications

• N-bit encoding systems
• Code converters and generators

Procurement Notes

Verify the specific ordering suffix against the manufacturer's current package option addendum to confirm the physical package type and production status. Confirm RoHS compliance and moisture sensitivity level ratings prior to procurement. Ensure that unused inputs are properly terminated to VCC or GND during implementation to maintain stable operation.

Selection Notes

Select this component when an 8-input priority encoding function is required in CMOS logic designs. Consider the wide operating voltage range and low power consumption benefits. Verify that the PDIP-16 through-hole package aligns with the target board assembly requirements and thermal constraints.

Part Context

This part belongs to the SNx4HC148 family of 8-line to 3-line priority encoders. It is available in various packages including SOIC, SOP, CDIP, and LCCC. The 'N' suffix specifically denotes the 16-pin PDIP package variant designed for through-hole mounting applications.

Replacement Considerations

SN74HC148DR

FAQ

How does the device handle multiple simultaneous active inputs?

The device performs priority decoding, ensuring that only the highest-order active data line is encoded into the binary output.

What is the purpose of the EI and EO pins?

The Enable Input (EI) and Enable Output (EO) signals allow for cascading multiple encoder stages to expand the number of encoded bits without requiring additional external circuitry.