MJD31C1G Equivalent & Substitute Parts

Part Overview

The MJD31C1G is an NPN bipolar junction transistor manufactured by onsemi, rated for 100 V collector-emitter breakdown voltage and 3 A maximum collector current. This device is packaged in a Through Hole I-PAK (TO-251-3) configuration and is designed for general-purpose switching and amplification applications requiring moderate power dissipation up to 1.56 W.

The MJD31C1G is classified as obsolete. Equivalent substitute parts are available in active product status, making substitution necessary for new designs and ongoing procurement requirements.

Substiute Parts

MJD31C1G

onsemiIn Stock: 1607MJD31C1G Datasheet

Current PartRFQ

MJD31CT4G

onsemiIn Stock: 35269MJD31CT4G Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the MJD31C1G is determined by electrical and mechanical parameter equivalence within the MJD31 base product family. The critical parameters that define substitutability are:

• Transistor Type: NPN configuration
• Maximum Collector Current (Ic): 3 A
• Collector-Emitter Breakdown Voltage (Vce(br)ceo): 100 V
• Saturation Voltage (Vce(sat)): 1.2 V @ specified conditions
• DC Current Gain (hFE): 10 (minimum) @ 3A, 4V
• Maximum Power Dissipation: 1.56 W
• Transition Frequency: 3 MHz
• Operating Temperature Range: -65°C to 150°C
• Compliance: ROHS3 Compliant, REACH Unaffected

The MJD31C1G (Through Hole I-PAK) can be substituted with the MJD31CT4G (Surface Mount DPAK) when circuit board layout and assembly process accommodate surface mount technology. Both devices share identical electrical specifications and compliance certifications. The primary difference is mounting technology: Through Hole versus Surface Mount.

Parameter Comparison

Engineering Selection Recommendations

The MJD31CT4G is the primary substitute for the obsolete MJD31C1G. Selection between these parts depends on circuit board assembly technology and design constraints:

Through Hole Applications (MJD31C1G): The original part is obsolete and no longer in active production. Existing inventory is limited to 1502 pieces. New designs should not specify this part.

Surface Mount Applications (MJD31CT4G): This is the recommended substitute for new designs and ongoing procurement. The MJD31CT4G is in active product status with substantial inventory availability (35200 pieces). All electrical parameters, compliance certifications (ROHS3, REACH Unaffected), and thermal specifications are identical to the MJD31C1G. The transition from Through Hole I-PAK to Surface Mount DPAK requires circuit board redesign and assembly process modification.

Both parts carry identical ROHS3 compliance and REACH Unaffected status, ensuring regulatory compatibility in equivalent applications. The MSL rating of 1 (Unlimited) for both parts indicates no moisture sensitivity constraints during storage or handling.

Frequently Asked Questions (FAQ)

Q: Can the MJD31CT4G directly replace the MJD31C1G on an existing printed circuit board?

A: No. The MJD31C1G uses Through Hole I-PAK (TO-251-3) mounting, while the MJD31CT4G uses Surface Mount DPAK (TO-252-3). These packages have different footprints, lead configurations, and soldering requirements. Circuit board layout and assembly processes must be modified to accommodate the surface mount package.

Q: Are the electrical specifications identical between MJD31C1G and MJD31CT4G?

A: Yes. Both devices share identical electrical ratings: 100 V collector-emitter breakdown voltage, 3 A maximum collector current, 1.56 W maximum power dissipation, 3 MHz transition frequency, and -65°C to 150°C operating temperature range. DC current gain (hFE), saturation voltage, and cutoff current specifications are also identical.

Q: Why is the MJD31C1G classified as obsolete?

A: The MJD31C1G is an older Through Hole package variant. onsemi has transitioned the MJD31 product line toward surface mount technology, represented by the active MJD31CT4G. Obsolete status indicates the part is no longer manufactured and existing inventory is limited.

Q: What is the difference between I-PAK and DPAK packages?

A: I-PAK (TO-251-3) is a Through Hole package with leads inserted into drilled holes on the circuit board. DPAK (TO-252-3) is a Surface Mount package with leads soldered directly to the board surface. DPAK packages typically offer improved thermal performance and higher component density compared to Through Hole alternatives.

Q: Are there compliance or regulatory differences between these parts?

A: No. Both the MJD31C1G and MJD31CT4G are ROHS3 Compliant and REACH Unaffected. Moisture Sensitivity Level (MSL) is 1 (Unlimited) for both parts, indicating no special storage or handling requirements.

Q: What is the inventory status for each part?

A: The MJD31C1G (obsolete) has 1502 pieces in stock. The MJD31CT4G (active) has 35200 pieces in stock. For new designs and long-term procurement, the MJD31CT4G is the appropriate choice due to active product status and higher availability.

Q: Can I use the MJD31CT4G in a design originally specified for the MJD31C1G?

A: Electrically, yes. All electrical parameters are identical. However, the circuit board must be redesigned to accommodate the surface mount DPAK package instead of the Through Hole I-PAK package. Assembly processes must also be modified for surface mount soldering.