M74HC148TTR

Overview

The M74HC148TTR is an 8-to-3 line priority encoder manufactured by STMicroelectronics, belonging to the 74HC logic series. It features a single circuit configuration within a 16-TSSOP surface-mount package. The device operates on a single power supply ranging from 2 V to 6 V, with typical operating voltages of 2.5 V, 3.3 V, and 5 V. Key electrical parameters include a maximum static current of 1 µA, output currents of 5.2 mA for both high and low states, and propagation delays varying between 43 ns and 50 ns depending on conditions. It supports an extended industrial temperature range from -55°C to +125°C.

Feature Summary

• Encodes eight active-low input lines into three-bit binary codes while prioritizing higher-order inputs.
• Provides cascading capability through enable input and enable output pins for expanding system capacity.
• Features active-low outputs compatible with standard digital logic interfaces.

Applications

• Interrupt controller systems requiring priority resolution among multiple signal sources
• Data acquisition modules for encoding sensor status bits
• Communication interface circuits for managing request line priorities

Procurement Notes

Verify component authenticity due to discontinued status. Confirm pinout compatibility with existing PCB layouts. Check RoHS compliance documentation for environmental regulations. Validate replacement options if original stock is unavailable. Ensure storage conditions prevent moisture damage prior to soldering.

Selection Notes

Select this component when designing systems requiring reliable priority encoding within the HC logic family voltage range. Consider the TSSOP package constraints for board space limitations. Evaluate thermal performance given the wide operating temperature specifications. Compare against alternative manufacturers if supply chain stability is a primary concern.

Part Context

This part belongs to the M74HC148 family of priority encoders produced by STMicroelectronics. It serves as a semiconductor solution for converting multiple input signals into encoded binary outputs. The device integrates CMOS technology to ensure low power consumption alongside robust noise immunity suitable for industrial environments.

Replacement Considerations

SN74HC148DR from Texas Instruments is a confirmed direct substitute.