Active dual 2:4 decoder — BOM-fit and supply rails
The SN74AHCT139D: Two independent 1-of-4 decoder/demultiplexer circuits in one 16-SOIC package. Each section takes a 2-bit binary address and a strobe input, decoding into four active-low outputs. Use it for memory chip-select generation, display multiplexing, or routing data to one of four destinations per bank. The 8 mA symmetric output drive (source and sink) handles standard CMOS loads, LED indicators with a series resistor, or driving low-power buffer inputs. The supply rail is the same 5 V rail used by many MCUs and DSPs listed in the same catalog category.
Industrial temperature grade and package constraints
This covers factory-floor control cabinets, outdoor telecom shelters, and automotive cabin environments. No derating needed for typical 5 V CMOS loads at the temperature extremes. 16-SOIC narrow body (3.90 mm width, 0.154" pitch, 1.27 mm lead pitch). The footprint matches legacy 74-series SOIC-16 layout — no board spin if replacing an older 74LS or 74HC dual decoder. Tube packaging means the parts arrive in antistatic tubes; reel/tape available on alternate order codes if needed for automated assembly.
ROHS3 compliance and procurement posture
ROHS3 compliant — no RoHS exemptions claimed. The part carries Texas Instruments' standard lead-free finish (matte tin on leads). Available through authorized and independent distribution channels.