CMPZ5221B BK PBFREE Equivalent & Substitute Parts

Part Overview

The CMPZ5221B BK PBFREE is a 2.4 V Zener diode manufactured by Central Semiconductor Corp, rated for 350 mW power dissipation in a surface mount SOT-23 package. This component is classified as Active product status with ROHS3 compliance and unlimited moisture sensitivity rating (MSL 1). Zener diodes of this specification are used in voltage regulation, overvoltage protection, and reference voltage circuits. Substitute parts are identified based on matching electrical characteristics and mechanical compatibility within the SOT-23 package family.

Key Parameters

Parameter	Value	Unit
Voltage - Zener (Nom)	2.4	V
Tolerance	±5%	-
Power - Max	350	mW
Impedance (Max)	30	Ohms
Current - Reverse Leakage @ Vr	100	µA @ 1 V
Voltage - Forward (Max) @ If	900	mV @ 10 mA
Operating Temperature Range	-65 to 150	°C
Mounting Type	Surface Mount	-
Package / Case	TO-236-3, SC-59, SOT-23-3	-
RoHS Status	ROHS3 Compliant	-

Substitute Part Grouping Explanation

Substitution of the CMPZ5221B BK PBFREE is determined by the following critical parameters:

Primary Matching Criteria:

Zener voltage: 2.4 V nominal
Package type: SOT-23 / TO-236-3 / SC-59 surface mount configurations
Operating temperature range: -65°C to 150°C minimum
RoHS3 compliance and MSL 1 rating

Secondary Compatibility Factors:

Power rating: 350 mW (main part) to 250-300 mW (substitute parts with reduced power dissipation remain compatible for lower-power applications)
Tolerance: ±5% (main part) to ±1% or ±2% (substitute parts with tighter tolerance provide improved performance)
Impedance: 30 Ohms (main part) to 100 Ohms (substitute parts with higher impedance acceptable for most applications)
Reverse leakage current: 100 µA @ 1 V (main part) to 50 µA @ 1 V (substitute parts with lower leakage provide improved performance)

Substitute parts are grouped by manufacturer and product status (Active vs. Obsolete). All listed substitutes maintain the 2.4 V zener voltage specification and SOT-23 package compatibility.

Parameter Comparison

Part Number	Manufacturer	Vz (V)	Tolerance	Power (mW)	Zzt (Ohms)	Leakage @ 1V (µA)	Temp Range (°C)	Status	Package
CMPZ5221B BK PBFREE	Central Semiconductor	2.4	±5%	350	30	100	-65 to 150	Active	SOT-23
MMBZ5221B-7-F	Diodes Incorporated	2.4	±5%	350	30	100	-65 to 150	Active	SOT-23-3
BZX84-A2V4,215	NXP USA Inc.	2.4	±1%	250	100	50	-65 to 150	Active	SOT-23
BZX84-A2V4,235	NXP USA Inc.	2.4	±1%	250	100	50	-65 to 150	Active	SOT-23
BZX84-B2V4,215	Nexperia USA Inc.	2.4	±2%	250	100	50	-65 to 150	Active	TO-236AB
BZX84-C2V4,215	NXP Semiconductors	2.4	±5%	250	100	50	-65 to 150	Active	TO-236AB
BZX84-C2V4,235	NXP USA Inc.	2.4	±5%	250	100	50	-65 to 150	Active	SOT-23
BZX84B2V4-E3-08	Vishay General Semiconductor	2.4	±2%	300	100	50	-55 to 150	Active	SOT-23-3
BZX84B2V4-HE3-08	Vishay General Semiconductor	2.4	±2%	300	100	50	-55 to 150	Obsolete	SOT-23-3
BZX84C2V4-E3-08	Vishay General Semiconductor	2.4	±5%	300	100	50	-55 to 150	Active	SOT-23-3
BZX84C2V4-HE3-08	Vishay General Semiconductor	2.4	±5%	300	100	50	-55 to 150	Obsolete	SOT-23-3

Engineering Selection Recommendations

Direct Equivalent (Identical Specifications):

MMBZ5221B-7-F from Diodes Incorporated is the direct equivalent to CMPZ5221B BK PBFREE. Both parts share identical electrical parameters: 2.4 V nominal zener voltage, ±5% tolerance, 350 mW power rating, 30 Ohms maximum impedance, and -65°C to 150°C operating range. Both are Active status products with ROHS3 compliance. The primary difference is packaging format (Tape & Reel vs. Bulk) and manufacturer. This part is suitable for direct substitution without circuit redesign.

Active Substitutes with Reduced Power Rating (250 mW):

BZX84-A2V4,215, BZX84-A2V4,235, BZX84-B2V4,215, and BZX84-C2V4,215/235 from NXP and Nexperia are Active status alternatives with 250 mW power rating. These parts maintain the 2.4 V zener voltage and SOT-23 package compatibility. The reduced power rating (250 mW vs. 350 mW) is acceptable for applications not requiring maximum power dissipation. NXP BZX84-A2V4 variants offer tighter ±1% tolerance. All maintain -65°C to 150°C operating range and ROHS3 compliance.

Active Substitutes with Intermediate Power Rating (300 mW):

BZX84B2V4-E3-08 and BZX84C2V4-E3-08 from Vishay General Semiconductor are Active status parts with 300 mW power rating, positioned between the main part (350 mW) and lower-rated NXP alternatives (250 mW). These Vishay parts maintain 2.4 V zener voltage and SOT-23-3 package compatibility. Operating temperature range is -55°C to 150°C (narrower low-temperature specification than the main part). Both are ROHS3 compliant.

Obsolete Status Parts (Not Recommended for New Designs):

BZX84B2V4-HE3-08 and BZX84C2V4-HE3-08 from Vishay are marked Obsolete product status. While electrically compatible with 300 mW power rating and 2.4 V zener voltage, these parts should not be selected for new circuit designs due to discontinued status.

Selection Priority for Active Designs:

MMBZ5221B-7-F (direct equivalent, highest inventory availability)
BZX84C2V4-E3-08 (Vishay, 300 mW, Active status, high inventory)
BZX84-C2V4,235 (NXP, 250 mW, Active status, highest inventory among NXP variants)

Frequently Asked Questions (FAQ)

Q: Can MMBZ5221B-7-F replace CMPZ5221B BK PBFREE in existing designs?

A: Yes. MMBZ5221B-7-F is a direct electrical equivalent with identical zener voltage (2.4 V), tolerance (±5%), power rating (350 mW), impedance (30 Ohms), and operating temperature range (-65°C to 150°C). Both use SOT-23 package. The only difference is packaging format (Tape & Reel vs. Bulk) and manufacturer. No circuit modifications are required.

Q: What is the difference between the 350 mW main part and 250 mW NXP substitutes?

A: Power rating indicates maximum continuous power dissipation capability. The 350 mW CMPZ5221B can dissipate more heat than 250 mW alternatives. For applications requiring full 350 mW dissipation, use CMPZ5221B or MMBZ5221B-7-F. For lower-power applications, 250 mW NXP parts (BZX84-A2V4, BZX84-C2V4) are acceptable and offer tighter tolerance (±1% for A-series). All maintain identical 2.4 V zener voltage.

Q: Are Vishay BZX84B2V4-E3-08 and BZX84C2V4-E3-08 suitable for new designs?

A: Yes. Both are Active status products with 300 mW power rating and 2.4 V zener voltage in SOT-23-3 package. The operating temperature range is -55°C to 150°C (lower limit is -55°C instead of -65°C). If your application requires operation below -55°C, use CMPZ5221B or MMBZ5221B-7-F instead. Otherwise, these Vishay parts are suitable for new designs.

Q: Why are BZX84B2V4-HE3-08 and BZX84C2V4-HE3-08 listed if they are Obsolete?

A: Obsolete parts are included for reference when analyzing existing circuit designs or legacy systems. These Vishay parts are electrically compatible but should not be selected for new product development. Use Active status alternatives instead.

Q: What does the SOT-23 vs. SOT-23-3 vs. TO-236AB package designation mean?

A: These are equivalent package designations for the same physical form factor. SOT-23, SOT-23-3, TO-236-3, SC-59, and TO-236AB all refer to the same 3-lead surface mount package with identical pin spacing and dimensions. Parts with these designations are mechanically and electrically interchangeable on the PCB.

Q: Can I use a 250 mW part in a circuit designed for 350 mW?

A: Only if your actual circuit power dissipation does not exceed 250 mW. The 350 mW rating is the maximum capability. If your design requires continuous operation at 300-350 mW dissipation, use the 350 mW CMPZ5221B or MMBZ5221B-7-F. For lower dissipation levels, 250 mW or 300 mW alternatives are acceptable.

Q: What is the significance of ±1%, ±2%, and ±5% tolerance ratings?

A: Tolerance indicates the accuracy of the zener voltage specification. CMPZ5221B has ±5% tolerance, meaning the actual zener voltage will be between 2.28 V and 2.52 V. NXP BZX84-A2V4 offers ±1% tolerance (2.376 V to 2.424 V), providing tighter voltage regulation. For precision voltage reference applications, select ±1% or ±2% parts. For general regulation, ±5% is acceptable.

Q: Are all listed substitutes ROHS3 compliant?

A: All Active status parts listed are ROHS3 compliant. Obsolete parts (BZX84B2V4-HE3-08, BZX84C2V4-HE3-08) are also ROHS3 compliant but should not be used in new designs.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message