Texas Instruments CD4556BE

Overview

CD4556BE from Texas Instruments is a dual 1-of-4 decoder/demultiplexer IC in a 16-pin PDIP package, operating across –55°C to +125°C, with supply voltage range 3 V to 18 V, and typical propagation delay of 120 ns at 5 V. It functions as a logic-level address decoder in industrial control panels requiring discrete output selection.

For engineers reviewing the CD4556BE datasheet, CD4556BE pinout, CD4556BE application, or CD4556BE equivalent, this page delivers verified package mapping, validated pin functions, confirmed timing specs, and two technically documented alternative parts for legacy CMOS logic design and replacement sourcing.

Technical Context

The CD4556BE implements two independent 1-of-4 decoders, each accepting two binary inputs (A0/A1) and enabling active-high outputs (Y0–Y3) when the associated enable input (E1/E2) is high. Inputs are CMOS-compatible with hysteresis for noise immunity.

It uses standard CD4000-series silicon-gate CMOS technology, ensuring low static power consumption (< 1 µA at 5 V), rail-to-rail output swing, and compatibility with TTL and other CMOS families via level-shifting design margins.

Key Specifications

Pinout & Package

CD4556BE is housed in a 16-lead plastic dual-in-line package (PDIP-N), 0.300-inch body width, with 0.100-inch lead pitch and standard DIP footprint compatible with through-hole assembly and socketing.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual 1-of-4 decoder applications.

Compared with CD4556BE, CD4556BF3A offers enhanced reliability in extreme environments but requires lead-free process waivers, while CD4556BM96 enables modern SMT manufacturing yet lacks through-hole serviceability for prototyping or field repair.

Availability

CD4556BE is available at Aetrix Electronics and suitable for industrial PLC expansion, automotive body control modules, and legacy microcontroller address decoding requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for CD4556BE includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader founded in 1930, specializing in analog, embedded processing, and logic solutions with broad industrial and automotive qualification.

The CD4556BE belongs to TI's legacy CD4000B series of buffered CMOS logic devices, designed specifically for high-reliability, wide-voltage industrial control and instrumentation applications where robustness and longevity are critical.

FAQ

What is the maximum operating frequency supported by the CD4556BE?

The CD4556BE does not specify a maximum clock frequency because it is a combinational logic device-not clocked. Its usable speed is determined by propagation delay: at 5 V, t_PD ≤ 120 ns, supporting reliable operation in address decode paths up to ~8 MHz. The CD4556BE remains stable across its full 3–18 V supply range, with delay scaling inversely with V_DD.

Can the CD4556BE replace the CD4555BE in a design?

No-CD4556BE and CD4555BE are functionally distinct. CD4555BE is a dual 1-of-2 decoder (2 inputs → 2 outputs), while CD4556BE is a dual 1-of-4 decoder (2 inputs → 4 outputs). Swapping them would require redesigning address mapping and output routing. The CD4556BE cannot emulate CD4555BE's output count or enable logic without external gating.

Is the CD4556BE pin-compatible with newer TI logic families like the 74HC4556?

No-CD4556BE uses standard CD4000-series pinout (dual decoder with shared V_DD/GND on pins 16/7), whereas 74HC4556 follows 74HC logic pinout (V_CC on pin 16, GND on pin 8, different enable and output assignments). Direct substitution would cause incorrect power connection and logic misbehavior. The CD4556BE requires its native footprint and biasing.

Does the CD4556BE support 3.3 V logic systems?

Yes-the CD4556BE operates down to 3 V, making it compatible with 3.3 V systems. However, at 3.3 V, output drive strength drops (~1.5 mA), and propagation delay increases (~250 ns). For robust 3.3 V interfacing, ensure downstream inputs meet CD4556BE's V_IH ≥ 2.3 V and V_IL ≤ 1.0 V thresholds. The CD4556BE remains fully functional but should be characterized in-circuit at that voltage.

What is the meaning of the "E" suffix in CD4556BE?

The "E" suffix in CD4556BE denotes the plastic dual-in-line package (PDIP-N) variant per TI's packaging nomenclature. It indicates RoHS-compliant NIPDAU lead finish, tube packaging (25 units), and commercial/military temperature range (–55°C to +125°C). This distinguishes it from "F3A" (ceramic DIP), "M96" (SOIC tape-and-reel), and other package variants-all sharing identical logic functionality but differing in mechanical and assembly attributes. The CD4556BE is the most widely stocked through-hole version.