1N4120-TP Zener Diode Equivalent & Substitute Parts

Part Overview

The 1N4120-TP is a 30 V, 500 mW Zener diode manufactured by Micro Commercial Co in DO-35 axial through-hole package. This component is classified as obsolete, with 759 units currently in stock. The part operates at a maximum junction temperature of 175°C and maintains ±5% voltage tolerance. Due to its obsolete status, equivalent substitute parts from active manufacturers are necessary for new designs and ongoing production requirements.

Key Parameters

Parameter	Value	Unit
Voltage - Zener (Nom)	30	V
Tolerance	±5%	-
Power - Max	500	mW
Impedance (Max)	200	Ohms
Voltage - Forward (Max) @ If	1.1	V @ 200 mA
Operating Temperature	175	°C (TJ)
Mounting Type	Through Hole	-
Package / Case	DO-204AH, DO-35, Axial	-
RoHS Status	ROHS3 Compliant	-

Substitute Part Grouping Explanation

Substitution of the 1N4120-TP is determined by the following critical parameters:

Electrical Equivalence Criteria:

Zener voltage: 30 V nominal
Power dissipation: 500 mW maximum
Forward voltage: 1.1 V maximum at 200 mA
Operating temperature range: minimum 175°C junction temperature capability
Package type: DO-35 axial through-hole configuration

Compliance Criteria:

RoHS3 compliance status
Moisture sensitivity level: 1 (Unlimited)
ECCN and HTSUS classifications

Substitute parts are grouped into two categories based on voltage tolerance specifications and impedance characteristics. Direct substitutes maintain ±5% tolerance matching the original part. Similar substitutes offer alternative tolerance grades (±1% or ±10%) and impedance values while maintaining core electrical specifications.

Parameter Comparison

Part Number	Manufacturer	Vz (Nom)	Tolerance	Power Max	Zzt (Max)	Vf (Max) @ If	Temp Range	Product Status	RoHS
1N4120-TP	Micro Commercial Co	30 V	±5%	500 mW	200 Ω	1.1 V @ 200 mA	-65 to 175°C	Obsolete	ROHS3
1N5256B-TR	Vishay General Semiconductor	30 V	±5%	500 mW	49 Ω	1.1 V @ 200 mA	-65 to 175°C	Active	ROHS3
1N6011A	Microchip Technology	30 V	±10%	500 mW	95 Ω	1.1 V @ 200 mA	-65 to 175°C	Active	Non-compliant
1N6011D	Microchip Technology	30 V	±1%	500 mW	78 Ω	1.1 V @ 200 mA	-65 to 175°C	Active	Non-compliant
BZX55C30-TAP	Vishay General Semiconductor	30 V	±5%	500 mW	80 Ω	1.5 V @ 200 mA	-65 to 175°C	Active	ROHS3
BZX55C30-TR	Vishay General Semiconductor	30 V	±5%	500 mW	80 Ω	1.5 V @ 200 mA	-65 to 175°C	Active	ROHS3
TZX30A-TAP	Vishay General Semiconductor	30 V	-	500 mW	100 Ω	1.5 V @ 200 mA	-65 to 175°C	Active	ROHS3
TZX30A-TR	Vishay General Semiconductor	30 V	-	500 mW	100 Ω	1.5 V @ 200 mA	-65 to 175°C	Active	ROHS3
TZX30B-TAP	Vishay General Semiconductor	30 V	-	500 mW	100 Ω	1.5 V @ 200 mA	-65 to 175°C	Active	ROHS3
TZX30B-TR	Vishay General Semiconductor	30 V	-	500 mW	100 Ω	1.5 V @ 200 mA	-65 to 175°C	Active	ROHS3
TZX30C-TAP	Vishay General Semiconductor	30 V	-	500 mW	100 Ω	1.5 V @ 200 mA	-65 to 175°C	Active	ROHS3

Engineering Selection Recommendations

Primary Substitute - Direct Electrical Match:

The 1N5256B-TR from Vishay General Semiconductor is the primary substitute for the 1N4120-TP. This part maintains identical electrical specifications: 30 V nominal Zener voltage, ±5% tolerance, 500 mW power rating, and 1.1 V forward voltage at 200 mA. The 1N5256B-TR is in active production status with ROHS3 compliance, ensuring long-term availability and regulatory conformance. The lower impedance value (49 Ω versus 200 Ω) provides improved performance characteristics while maintaining functional compatibility.

Secondary Substitutes - Tolerance Variants:

The BZX55C30-TR and BZX55C30-TAP series from Vishay maintain ±5% tolerance matching and are AEC-Q101 qualified for automotive applications. These parts feature 80 Ω impedance and 1.5 V forward voltage. Both variants are in active production with ROHS3 compliance.

The TZX30 series (TZX30A-TR, TZX30A-TAP, TZX30B-TR, TZX30B-TAP, TZX30C-TAP) from Vishay provides alternative impedance characteristics at 100 Ω with 1.5 V forward voltage. All TZX30 variants are AEC-Q101 qualified, in active production, and ROHS3 compliant.

Alternative Tolerance Options:

The 1N6011D from Microchip Technology offers ±1% tolerance for applications requiring tighter voltage regulation. The 1N6011A provides ±10% tolerance for less stringent applications. Both Microchip parts are in active production but are not RoHS3 compliant.

Frequently Asked Questions (FAQ)

Q: Can the 1N5256B-TR directly replace the 1N4120-TP without circuit modifications?

A: Yes. The 1N5256B-TR maintains identical nominal Zener voltage (30 V), tolerance (±5%), power rating (500 mW), and forward voltage specifications (1.1 V @ 200 mA). Both parts use DO-35 axial through-hole packaging. The lower impedance of the 1N5256B-TR (49 Ω versus 200 Ω) represents improved performance and does not require circuit changes.

Q: What is the difference between the BZX55C30 and TZX30 series?

A: Both series are 30 V, 500 mW Zener diodes in DO-35 packages from Vishay. The BZX55C30 maintains ±5% tolerance with 80 Ω impedance and 1.5 V forward voltage. The TZX30 series does not specify tolerance with 100 Ω impedance and 1.5 V forward voltage. Both are AEC-Q101 qualified and ROHS3 compliant. Selection depends on tolerance requirements and impedance specifications for the application.

Q: Why do some substitute parts show higher forward voltage (1.5 V) compared to the original (1.1 V)?

A: Forward voltage variation is a characteristic difference between device families and manufacturing processes. The 1.5 V forward voltage of BZX55C30 and TZX30 series remains within acceptable operating parameters for 30 V Zener diodes. Circuit designs must account for this specification when forward current conduction is a factor.

Q: Are the Microchip 1N6011A and 1N6011D suitable replacements despite RoHS non-compliance?

A: The 1N6011A and 1N6011D are electrically compatible with the 1N4120-TP. However, RoHS non-compliance may restrict their use in applications subject to RoHS3 regulations. The 1N6011D offers superior ±1% tolerance for precision applications, while the 1N6011A provides ±10% tolerance for general-purpose use. Compliance requirements must be evaluated against application constraints.

Q: What packaging options are available for substitute parts?

A: Substitute parts are available in Cut Tape (CT), Tape & Box (TB), and Bulk packaging formats. The packaging designation does not affect electrical performance or physical form factor. All substitute parts maintain DO-35 axial through-hole configuration compatible with the original 1N4120-TP footprint. Packaging selection is determined by procurement and assembly requirements.

Q: Why is the 1N4120-TP classified as obsolete?

A: The 1N4120-TP is an older design from Micro Commercial Co. Active substitutes from Vishay and Microchip offer equivalent or superior electrical characteristics with ongoing production support and regulatory compliance. Obsolete status indicates the original manufacturer has discontinued production, making active alternatives necessary for new designs and long-term supply chain stability.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message