M74HC139B1R

Overview

The M74HC139B1R is a dual 2-to-4 decoder/demultiplexer manufactured by STMicroelectronics using silicon gate C2MOS technology. It operates within a supply voltage range of 2V to 6V and supports an operating temperature from -55°C to +125°C. The device features active low enable inputs for gating or demultiplexing, with outputs held high when enabled. It includes input protection against static discharge and transient excess voltage.

Feature Summary

• Dual independent 2-to-4 decoding circuits
• Active low enable inputs for gating control
• High noise immunity with symmetrical output impedance
• Balanced propagation delays between address and enable paths

Applications

• Address decoding in microprocessor systems
• Data demultiplexing applications
• Gating logic control
• Memory chip select generation

Procurement Notes

Verify component obsolescence status before procurement as the part is marked obsolete. Confirm DIP-16 package availability through authorized distributors. Check RoHS compliance documentation for specific manufacturing lot requirements. Ensure storage conditions meet specified limits to prevent degradation.

Selection Notes

Select this component for designs requiring dual decoding functions in HC logic families. Verify voltage compatibility with system supply rails between 2V and 6V. Consider thermal dissipation limits when operating at elevated temperatures. Evaluate pin compatibility with existing 74-series layouts for direct replacement scenarios.

Part Context

Part of the M74HC139 series offering dual decoder functionality. Manufactured using CMOS technology for low power consumption. Compatible with standard 74-series logic interfaces. Available in multiple package types including DIP, SOP, and TSSOP configurations.

Replacement Considerations

CD74HC138E and SN74HC138N are listed as similar alternatives. Verify functional equivalence for specific application requirements. Check pinout compatibility for direct substitution. Confirm electrical specifications match design constraints.