J201_D74Z JFET N-Channel Equivalent & Substitute Parts

Part Overview

The J201_D74Z is an N-Channel JFET manufactured by onsemi, rated for 40 V breakdown voltage with a maximum power dissipation of 625 mW in a through-hole TO-92-3 package. This device is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing design support and production continuity. Substitute parts must maintain electrical performance across drain current, gate-source voltage characteristics, and thermal operating range while accommodating different mounting technologies.

Substiute Parts

J201_D74Z

onsemiIn Stock: 964J201_D74Z Datasheet

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MMBFJ201

onsemiIn Stock: 76135MMBFJ201 Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution of the J201_D74Z is determined by strict equivalence across electrical characteristics and thermal performance. The critical parameters governing substitutability are:

• FET Type: N-Channel configuration must be maintained
• Voltage - Breakdown (V(BR)GSS): 40 V minimum rating required
• Current - Drain (Idss): 200 µA @ 20 V specification must be met
• Voltage - Cutoff (VGS off): 300 mV @ 10 nA threshold specification must be matched
• Operating Temperature Range: -55°C to 150°C (TJ) must be supported

The MMBFJ201 qualifies as an electrical equivalent based on identical FET type, breakdown voltage, drain current, and cutoff voltage specifications. The primary distinction is mounting technology: the J201_D74Z uses through-hole TO-92-3 packaging, while the MMBFJ201 uses surface-mount SOT-23-3 packaging. Power dissipation differs (625 mW vs. 350 mW), which may affect thermal design considerations in high-power applications.

Parameter Comparison

Engineering Selection Recommendations

The MMBFJ201 provides electrical equivalence to the J201_D74Z across all specified DC and thermal parameters. Selection between these parts depends on circuit implementation requirements:

For through-hole PCB designs requiring the original TO-92-3 package form factor, the J201_D74Z remains available with 855 pieces in current inventory, despite obsolete status.

For new designs or redesigns accommodating surface-mount technology, the MMBFJ201 is the preferred selection. It maintains full electrical equivalence, operates across the identical temperature range, and carries active product status with significantly higher inventory availability (76,050 pieces). The MMBFJ201 is RoHS3 compliant, providing regulatory advantage for modern applications.

Power dissipation reduction from 625 mW to 350 mW in the MMBFJ201 requires thermal design verification in applications approaching maximum power limits. Circuits operating below 350 mW dissipation experience no thermal constraint.

Both parts share identical REACH and ECCN classifications, ensuring equivalent compliance status for export and supply chain purposes.

Frequently Asked Questions (FAQ)

Q: Can the MMBFJ201 directly replace the J201_D74Z in existing through-hole designs?

A: Electrical substitution is valid. However, the MMBFJ201 uses SOT-23-3 surface-mount packaging, requiring PCB layout modification. Direct socket replacement is not possible without adapter hardware or circuit board redesign.

Q: What is the impact of reduced power dissipation in the MMBFJ201?

A: The MMBFJ201 maximum power rating is 350 mW versus 625 mW for the J201_D74Z. Applications dissipating less than 350 mW experience no functional impact. Circuits designed for higher power operation require thermal analysis to confirm the substitute remains within safe operating limits.

Q: Are the electrical characteristics identical between these parts?

A: Yes. Breakdown voltage (40 V), drain current (200 µA @ 20 V), cutoff voltage (300 mV @ 10 nA), and operating temperature range (-55°C to 150°C) are identical. Both are N-Channel JFETs with equivalent DC performance.

Q: Which part should be selected for new production?

A: The MMBFJ201 is recommended for new designs. It carries active product status, offers superior inventory availability, and is RoHS3 compliant. The J201_D74Z is obsolete and should be reserved for legacy system support only.

Q: Are there compliance or certification differences?

A: Both parts share REACH Unaffected and EAR99 ECCN classifications. The MMBFJ201 adds RoHS3 compliance, providing regulatory advantage for applications subject to RoHS requirements.