CD4518BM Equivalent & Substitute Parts

Part Overview

The CD4518BM is a dual 4-bit BCD counter logic integrated circuit manufactured by Texas Instruments in the 4000B series. This component functions as a synchronous counter with asynchronous reset, capable of counting in binary-coded decimal format across two independent 4-bit elements. The CD4518BM is currently in Last Time Buy status, indicating that Texas Instruments has discontinued active production. This status necessitates identification of equivalent substitute parts to ensure design continuity and procurement availability for new production runs and field replacements.

Substiute Parts

CD4518BM

Texas InstrumentsIn Stock: 1269CD4518BM Datasheet

Current PartRFQ

CD4518BM96

Texas InstrumentsIn Stock: 19714CD4518BM96 Datasheet

MFR RecommendedRFQ

MC14518BDWG

onsemiIn Stock: 1225MC14518BDWG Datasheet

DirectRFQ

HEF4518BT,653

Nexperia USA Inc.In Stock: 7450HEF4518BT,653 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the CD4518BM is determined by strict alignment with the following critical parameters:

Functional Requirements:

• Logic Type: BCD Counter (2 elements, 4 bits per element)
• Direction: Up counting only
• Reset: Asynchronous capability
• Trigger Type: Positive and Negative edge triggering

Electrical Requirements:

• Voltage Supply Range: Must encompass or be compatible with 3 V ~ 18 V
• Count Rate: Minimum 8 MHz operational capability
• Operating Temperature: Must support -55°C ~ 125°C range or a subset thereof

Physical & Compliance Requirements:

• Package / Case: 16-SOIC form factor with compatible pinout
• Mounting Type: Surface Mount
• RoHS Status: ROHS3 Compliant
• Moisture Sensitivity: MSL 1 or MSL 3 acceptable for standard applications

Substitute parts are grouped based on manufacturer origin and packaging configuration while maintaining functional and electrical equivalence.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: CD4518BM96

The CD4518BM96 is the manufacturer-recommended substitute from Texas Instruments. This part maintains identical electrical specifications, temperature range, voltage supply range, and package dimensions as the CD4518BM. The only difference is packaging configuration (Tape & Reel versus Tube), which does not affect functional performance. Product status is Active, ensuring long-term availability. This is the preferred choice for direct replacement in new designs and production continuity.

Secondary Substitute: HEF4518BT,653

The HEF4518BT,653 from Nexperia USA Inc. provides functional equivalence with identical logic type, element count, bit width, and trigger capabilities. This part operates at a higher count rate (40 MHz versus 8 MHz), providing performance margin. However, the operating temperature range is narrower (-40°C ~ 85°C versus -55°C ~ 125°C) and the supply voltage range is more restricted (4.5 V ~ 15.5 V versus 3 V ~ 18 V). Selection of this part requires confirmation that the application does not require the extended temperature or voltage specifications of the CD4518BM. Product status is Active.

Tertiary Substitute: MC14518BDWG

The MC14518BDWG from onsemi maintains full functional equivalence across all critical parameters including voltage supply range, temperature range, and logic specifications. The package width differs (0.295" versus 0.154"), which may require PCB layout modification. Moisture Sensitivity Level is MSL 3 (168 Hours) rather than MSL 1, requiring controlled storage and handling procedures. Product status is Active.

Frequently Asked Questions (FAQ)

Q: Can CD4518BM96 be used as a direct replacement for CD4518BM?

A: Yes. CD4518BM96 is the manufacturer-recommended substitute from Texas Instruments. Both parts share identical electrical specifications, temperature range, voltage supply range, and package dimensions. The difference is packaging format (Tape & Reel versus Tube), which does not affect circuit performance or pinout compatibility.

Q: What are the key differences between CD4518BM and HEF4518BT,653?

A: Both parts are functionally equivalent BCD counters with identical logic architecture. The HEF4518BT,653 operates at 40 MHz versus 8 MHz, providing higher speed capability. However, the operating temperature range is narrower (-40°C ~ 85°C versus -55°C ~ 125°C) and the supply voltage range is more restricted (4.5 V ~ 15.5 V versus 3 V ~ 18 V). Applications requiring extended temperature or voltage specifications must use CD4518BM, CD4518BM96, or MC14518BDWG.

Q: Is the MC14518BDWG package compatible with CD4518BM PCB layouts?

A: The MC14518BDWG uses a 16-SOIC package with 0.295" width compared to 0.154" width for CD4518BM. While the pinout is identical, the physical footprint differs, requiring PCB layout modification. Consult the respective datasheets for exact pad spacing and placement requirements.

Q: What is the significance of Moisture Sensitivity Level differences?

A: CD4518BM and CD4518BM96 have MSL 1 (Unlimited), allowing indefinite storage without moisture control. MC14518BDWG has MSL 3 (168 Hours), requiring that the component be used within 168 hours of package opening under controlled humidity conditions. HEF4518BT,653 has MSL 1. Applications with extended storage or high-humidity environments should prioritize MSL 1 rated parts.

Q: Can these substitutes be used interchangeably in all applications?

A: Functional substitution is possible only when the application requirements fall within the electrical and temperature specifications of the substitute part. Applications requiring the full -55°C ~ 125°C temperature range or 3 V ~ 18 V supply voltage range must use CD4518BM, CD4518BM96, or MC14518BDWG. Applications with narrower requirements may use HEF4518BT,653. PCB layout compatibility must be verified for MC14518BDWG due to package width differences.