CD4556BF Equivalent & Substitute Parts

Part Overview

The CD4556BF is a CMOS dual binary to 1-of-4 decoder/demultiplexer manufactured by Texas Instruments. This logic component operates as a decoder/demultiplexer with a 1 x 2:4 circuit configuration and features dual independent circuits. The device is currently in active product status with 1530 pieces available in new original stock.

Identification of equivalent and substitute parts becomes necessary when the primary part number is unavailable, when supply chain constraints occur, or when design flexibility permits selection from functionally compatible alternatives. The CD4556BF has documented substitute options that maintain electrical and mechanical compatibility within specified parameters.

Substiute Parts

CD4556BF

Texas InstrumentsIn Stock: 1544CD4556BF Datasheet

Current PartRFQ

CD4556BE

Harris CorporationIn Stock: 7652CD4556BE Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the CD4556BF is determined by strict equivalence across the following critical parameters:

Electrical Compatibility Requirements:

• Decoder/Demultiplexer circuit configuration: 1 x 2:4
• Independent circuits: 2
• Output current specifications: 6.8 mA (both high and low)
• Voltage supply source: Dual Supply
• Supply voltage range: 3V ~ 18V
• Operating temperature range: -55°C ~ 125°C

Mechanical Compatibility Requirements:

• Mounting type: Through Hole
• Package footprint: 16-DIP or 16-CDIP with 0.300" (7.62mm) body width

The CD4556BE qualifies as a substitute part because it maintains identical electrical specifications across all output current, voltage supply, and temperature parameters. Both parts feature the same 1 x 2:4 decoder/demultiplexer configuration with dual independent circuits. The mechanical compatibility is confirmed through equivalent through-hole mounting and compatible 16-DIP package dimensions (0.300", 7.62mm).

Parameter Comparison

Engineering Selection Recommendations

CD4556BF Selection Criteria: The CD4556BF is the primary selection for new designs and applications requiring active product status. This part maintains ROHS3 compliance, meeting current environmental and regulatory standards. With 1530 pieces in new original stock, availability is established for production requirements.

CD4556BE Selection Criteria: The CD4556BE is classified as obsolete and does not meet ROHS3 compliance standards. This part should be selected only in legacy system maintenance scenarios where existing designs already incorporate this component. The CD4556BE maintains full electrical and mechanical compatibility with the CD4556BF across all critical parameters, enabling functional substitution in through-hole applications. However, the obsolete product status and RoHS non-compliance status indicate this part is not suitable for new design implementations.

Compliance Considerations: Applications subject to RoHS3 environmental regulations must use the CD4556BF. Applications without RoHS compliance requirements may use either part, provided that supply chain and inventory constraints do not apply.

Frequently Asked Questions (FAQ)

Q: Can the CD4556BE be used as a direct replacement for the CD4556BF in new designs?

A: The CD4556BE maintains electrical and mechanical compatibility with the CD4556BF across all critical parameters including circuit configuration, output current, voltage supply range, and operating temperature. However, the CD4556BE is classified as obsolete and does not meet ROHS3 compliance. New designs should specify the CD4556BF to ensure compliance with current environmental standards and to maintain access to active product support.

Q: Are the package dimensions identical between CD4556BF and CD4556BE?

A: Both parts feature through-hole mounting with compatible 16-DIP package dimensions of 0.300" (7.62mm) body width. The CD4556BF uses 16-CDIP packaging while the CD4556BE uses 16-DIP packaging. These package variants are mechanically compatible for PCB footprint purposes.

Q: What are the key electrical parameters that determine substitution compatibility?

A: Substitution compatibility is determined by equivalence in the following parameters: decoder/demultiplexer circuit configuration (1 x 2:4), independent circuits (2), output current specifications (6.8 mA high and low), voltage supply source (dual supply), supply voltage range (3V ~ 18V), and operating temperature range (-55°C ~ 125°C). Both the CD4556BF and CD4556BE meet these specifications.

Q: Why is the CD4556BE listed as obsolete?

A: The CD4556BE is a legacy product manufactured by Harris Corporation and is no longer in active production. The Texas Instruments CD4556BF represents the current active equivalent in the product line.

Q: What is the difference between ROHS3 compliance and RoHS non-compliance?

A: ROHS3 compliance indicates the part meets current Restriction of Hazardous Substances regulations, restricting the use of specific hazardous materials in electrical and electronic equipment. RoHS non-compliance indicates the part does not meet these restrictions and may contain prohibited substances. Applications subject to environmental regulations must use ROHS3 compliant parts.