CD4051BCMX Equivalent & Substitute Parts

Part Overview

The CD4051BCMX is a single-circuit 8:1 multiplexer/demultiplexer interface IC manufactured by onsemi, housed in a 16-SOIC surface mount package. This part features an on-state resistance of 240Ω and operates across a wide supply voltage range of 5V to 15V (single supply) or ±2.5V to ±7.5V (dual supply). The CD4051BCMX is classified as obsolete, making equivalent substitute parts necessary for new designs and ongoing production requirements. Substitute parts must maintain functional compatibility through matching multiplexer configuration, package type, and operating temperature range while accommodating variations in on-state resistance and supply voltage specifications.

Key Parameters

Parameter	CD4051BCMX
Multiplexer/Demultiplexer Circuit	8:1
Number of Circuits	1
On-State Resistance (Max)	240Ω
Channel-to-Channel Matching (ΔRon)	5Ω
Voltage - Supply, Single (V+)	5V ~ 15V
Voltage - Supply, Dual (V±)	±2.5V ~ 7.5V
Switch Time (Ton, Toff) (Max)	320ns, 150ns
-3dB Bandwidth	40MHz
Current - Leakage (IS(off)) (Max)	50nA
Crosstalk	-40dB @ 3MHz
Operating Temperature	-55°C ~ 125°C (TA)
Mounting Type	Surface Mount
Package / Case	16-SOIC (0.154", 3.90mm Width)
Moisture Sensitivity Level (MSL)	1 (Unlimited)

Substitute Part Grouping Explanation

Substitution of the CD4051BCMX is determined by the following core parameters:

Mandatory Compatibility Criteria:

Multiplexer/Demultiplexer configuration: 8:1
Number of circuits: 1
Package type: 16-SOIC surface mount
Operating temperature range: -55°C ~ 125°C
Mounting type: Surface mount

Variable Parameters Allowing Substitution:

On-state resistance (240Ω baseline; substitutes range from 26Ω to 280Ω)
Supply voltage specifications (single or dual supply options)
Bandwidth and switching characteristics
Leakage current specifications

Substitute parts are grouped into three technology families based on on-state resistance and supply voltage compatibility: CMOS standard (MC14051 series at 280Ω), high-speed CMOS (74HC4051/74HCT4051 series at 100Ω), and low-voltage CMOS (74LVX4051/74LVXT4051/74VHC4051 series at 26Ω). Each family maintains the 8:1 multiplexer function and 16-SOIC package footprint while offering different electrical performance characteristics.

Parameter Comparison

Part Number	Manufacturer	On-State Resistance (Max)	ΔRon (Max)	V+ Supply	V± Supply	-3dB Bandwidth	IS(off) (Max)	Package	Product Status	RoHS Status
CD4051BCMX	onsemi	240Ω	5Ω	5V ~ 15V	±2.5V ~ 7.5V	40MHz	50nA	16-SOIC (3.90mm)	Obsolete	REACH Unaffected
MC14051BDG	onsemi	280Ω	10Ω	3V ~ 18V	—	17MHz	100nA	16-SOIC (3.90mm)	Active	ROHS3 Compliant
MC14051BDR2G	onsemi	280Ω	10Ω	3V ~ 18V	—	17MHz	100nA	16-SOIC (3.90mm)	Active	ROHS3 Compliant
MC74HC4051ADG	onsemi	100Ω	10Ω	2V ~ 6V	±2V ~ 6V	80MHz	200nA	16-SOIC (3.90mm)	Active	ROHS3 Compliant
MC74HC4051ADR2G	onsemi	100Ω	10Ω	2V ~ 6V	±2V ~ 6V	80MHz	200nA	16-SOIC (3.90mm)	Active	ROHS3 Compliant
MC74HCT4051ADG	onsemi	100Ω	10Ω	2V ~ 6V	±2V ~ 6V	80MHz	200nA	16-SOIC (7.50mm)	Active	ROHS3 Compliant
MC74HCT4051ADR2G	onsemi	100Ω	10Ω	2V ~ 6V	±2V ~ 6V	80MHz	200nA	16-SOIC (7.50mm)	Active	ROHS3 Compliant
MC74LVX4051DG	onsemi	26Ω	10Ω	2.5V ~ 6V	±2.5V ~ 6V	80MHz	100nA	16-SOIC (3.90mm)	Active	ROHS3 Compliant
MC74LVX4051DR2G	onsemi	26Ω	10Ω	2.5V ~ 6V	±2.5V ~ 6V	80MHz	100nA	16-SOIC (3.90mm)	Active	ROHS3 Compliant
MC74LVXT4051DR2G	onsemi	26Ω	10Ω	2.5V ~ 6V	±2.5V ~ 6V	80MHz	100nA	16-SOIC (3.90mm)	Active	ROHS3 Compliant
MC74VHC4051DR2G	onsemi	100Ω	10Ω	2V ~ 6V	±2V ~ 6V	80MHz	100nA	16-SOIC (3.90mm)	Active	ROHS3 Compliant

Engineering Selection Recommendations

CMOS Standard Family (MC14051 Series): MC14051BDG and MC14051BDR2G are active production alternatives with extended single-supply voltage range (3V to 18V). These parts are suitable for applications requiring lower bandwidth (17MHz) and higher on-state resistance (280Ω). Both are ROHS3 compliant. Selection between tube (BDG) and cut tape/digi-reel (BDR2G) packaging depends on procurement and assembly requirements.

High-Speed CMOS Family (74HC4051/74HCT4051 Series): MC74HC4051ADG, MC74HC4051ADR2G, MC74HCT4051ADG, and MC74HCT4051ADR2G offer improved bandwidth (80MHz) and reduced on-state resistance (100Ω) compared to the CD4051BCMX. These parts support dual supply operation (±2V to ±6V) and are ROHS3 compliant. The 74HCT variants feature TTL-compatible input thresholds. Package width differs between standard (3.90mm) and HCT variants (7.50mm); verify PCB footprint compatibility before selection.

Low-Voltage CMOS Family (74LVX4051/74LVXT4051/74VHC4051 Series): MC74LVX4051DG, MC74LVX4051DR2G, MC74LVXT4051DR2G, and MC74VHC4051DR2G provide the lowest on-state resistance (26Ω) and highest bandwidth (80MHz). These parts operate at reduced supply voltages (2.5V to 6V single supply or ±2.5V to ±6V dual supply) and are ROHS3 compliant. Selection among these variants depends on packaging preference (tube, tape & reel, or cut tape) and specific application voltage requirements.

All substitute parts maintain the 16-SOIC surface mount package footprint, 8:1 multiplexer configuration, and -55°C to 125°C operating temperature range of the CD4051BCMX. All listed substitutes are REACH unaffected and carry ROHS3 compliance certification.

Frequently Asked Questions (FAQ)

Q: Can MC14051BDG directly replace CD4051BCMX in existing designs? A: MC14051BDG maintains the 8:1 multiplexer function, 16-SOIC package, and operating temperature range. However, the on-state resistance increases from 240Ω to 280Ω, and bandwidth decreases from 40MHz to 17MHz. Supply voltage range expands to 3V–18V (single supply only). Verify that your circuit tolerates these parameter changes before substitution.

Q: What is the difference between MC74HC4051ADG and MC74HCT4051ADG? A: Both parts offer identical electrical performance (100Ω on-state resistance, 80MHz bandwidth, dual supply operation). The primary difference is input threshold compatibility: 74HC uses CMOS-level thresholds, while 74HCT uses TTL-compatible thresholds. The 74HCT variant also features a wider 16-SOIC package (7.50mm vs. 3.90mm). Select based on your system's logic level requirements and PCB layout constraints.

Q: Why do some substitutes have lower on-state resistance than the CD4051BCMX? A: Lower on-state resistance (26Ω in 74LVX/74LVXT/74VHC families vs. 240Ω in CD4051BCMX) results from advanced CMOS process technology. Lower resistance reduces signal attenuation and improves bandwidth performance. This is beneficial for most applications; however, verify that your circuit design does not depend on the higher impedance of the original part.

Q: Are all substitute parts RoHS compliant? A: All listed substitute parts are ROHS3 compliant and REACH unaffected. The CD4051BCMX is classified as obsolete and does not carry RoHS certification. For new designs and production requiring regulatory compliance, select from the active substitute parts listed.

Q: What packaging options are available for the 74LVX4051 family? A: MC74LVX4051DG is supplied in tube packaging, MC74LVX4051DR2G in tape & reel format, and MC74LVXT4051DR2G in cut tape format. Select packaging based on your procurement volume and assembly process requirements.

Q: Can I use a substitute part with lower supply voltage range in a 15V application? A: No. The 74HC4051, 74HCT4051, 74LVX4051, 74LVXT4051, and 74VHC4051 families are rated for maximum single-supply voltages of 2V–6V or dual supplies of ±2V–±6V. These parts are not suitable for 15V applications. Only MC14051BDG and MC14051BDR2G support the extended voltage range (3V–18V single supply) required for higher-voltage circuits.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message