MJ2955 - 15A 60V PNP Power Transistor | TO-3 | onsemi
MPN: MJ2955 ✓ فعالMJ2955 جائزہ
A bipolar junction transistor (BJT) is a three-terminal semiconductor device that uses a small base current to control a much larger collector current, achieving current gain typically expressed as hFE. Power BJTs like the MJ2955 are optimized for high-current and high-voltage switching or linear amplification, where their low saturation voltage and robust SOA are advantageous. Within the power semiconductor hierarchy, the MJ2955 sits as a PNP power BJT, complementary to NPN power BJTs such as the 2N3055, and is typically deployed where polarity-symmetric drive or negative-rail regulation is required.
Key features include 60 V VCBO, 7 A continuous base current, an epitaxial-base planar die for tight parametric distribution, and hermetic TO-3 metal packaging rated for chassis-mount heatsink attachment. The TO-3 case provides low thermal resistance, high mechanical ruggedness, and a bolt-down mounting style that suits industrial, audio, and military-grade applications where long-term reliability is critical.
The MJ2955 uses an epitaxial-base mesa structure delivering typical DC current gain (hFE) of 20 to 70 at IC = 4 A, supporting both linear amplification and saturated switching. Its collector-emitter saturation voltage of approximately 1.1 V at rated current makes it efficient in linear regulators and audio output stages, while the 4 MHz transition frequency supports moderate-bandwidth amplifier designs.
Typical applications include linear power supplies and series regulators, hi-fi audio amplifier output stages, DC motor drivers, inverter and converter stages, and general-purpose high-power switching. The MJ2955's complementary nature to the 2N3055 makes it a standard choice for push-pull Class AB amplifier output pairs.
When designing with this device, always use a proper mica or silicone-insulated heatsink mount and ensure the collector case potential is acceptable for your circuit topology, since the TO-3 case is electrically tied to the collector. Keep base drive current within the rated 7 A limit and observe the SOAR curve at high VCE.
This page synthesizes distributor pricing, drop-in TO-3 alternatives, and practical heatsink design notes not consolidated on the manufacturer datasheet, giving procurement and design engineers a single reference for sourcing and substituting the MJ2955.
کے لیے ڈراپ اِن متبادل MJ2955 — یکساں پیکیج، پن سے پن مطابقت پذیر۔ مختلف پیکیج والے پرزے جن کے لیے PCB دوبارہ کام درکار ہو، شامل نہیں ہیں۔
اس سیریز میں مختلف ورژن
اسی سیریز کے ماڈلز جو ڈراپ اِن مطابقت رکھتے ہیں MJ2955 (یکساں فارم فیکٹر اور فٹ پرنٹ) — میں مختلف Mounting Type, Package, Polarity.
MJ2955G
✅ ڈراپ-اِن📋 حوالہ جاتی متبادل (کیٹلاگ میں نہیں)
2N2955
✅ ڈراپ-اِن📋 حوالہ جاتی متبادل (کیٹلاگ میں نہیں)
MJ15016
✅ ڈراپ-اِن📋 حوالہ جاتی متبادل (کیٹلاگ میں نہیں)
2N5880
✅ ڈراپ-اِن📋 حوالہ جاتی متبادل (کیٹلاگ میں نہیں)
2N6248
✅ ڈراپ-اِن📋 حوالہ جاتی متبادل (کیٹلاگ میں نہیں)
MJ2955
✅ ڈراپ-اِنقیمت کے لیے رابطہ کریں
ڈیٹا شیٹ دیکھیں →MJ2955 زیادہ سے زیادہ ریٹنگز اور برقی خصوصیات
| ٹرانزسٹر کی قسم | PNP |
| Polarity | PNP (complement of 2N3055) |
| کلیکٹر-ایمیٹر وولٹیج (Vceo) | 60 V |
| کلیکٹر-بیس وولٹیج (Vcbo) | 60 V |
| ایمیٹر-بیس وولٹیج (Vebo) | 7 V |
| Continuous Collector Current (IC) | 15 A |
| Continuous Base Current (IB) | 7 A |
| Power Dissipation (PD) | 115 W at 25 °C case |
| Junction-to-Case Thermal Resistance (θJC) | 1.52 °C/W |
| DC Current Gain (hFE) | 20 to 70 (at IC = 4 A, VCE = 4 V) |
| کلیکٹر-ایمیٹر سیچوریشن وولٹیج (Vce(sat)) | 1.1 V typical (at IC = 15 A) |
| ٹرانزیشن فریکوئنسی (ft) | 4 MHz |
| آپریٹنگ جنکشن درجہ حرارت | -65 °C to +200 °C |
| پیکیج | TO-3 (TO-204-3) metal case |
| ماؤنٹنگ ٹائپ | Chassis / Through-hole bolt-down |
| RoHS اسٹیٹس | Compliant |
MJ2955 پن کنفیگریشن
| پن 1 | Base — Base control terminal |
| پن 2 | Emitter — Emitter terminal |
| پن 3 | Collector — Collector - internally bonded to metal case |
محفوظ آپریٹنگ ایریا (DC, TJ <= 200 °C)
عام استعمالات
MJ2955 کے لیے موزوں ہے 6 ایپلیکیشنs: Linear Power Supply Series Regulator, Hi-Fi Audio Amplifier Output Stage, DC Motor Driver / H-Bridge, Battery Charger Current Source, Power Inverter / Switch-Mode Output Stage, Automotive Voltage Regulator / Alternator Control.
Linear Power Supply Series Regulator
The MJ2955 is a workhorse for linear series-pass regulators where its 60 V VCEO and 15 A continuous collector current deliver ample headroom for 5 V to 48 V rails. Its low 1.1 V VCE(sat) and 1.52 °C/W θJC reduce waste heat compared to Darlington alternatives. Designers bias the base from a TL431 reference through a driver transistor, with the MJ2955 dissipating up to 115 W on a bolted heatsink. The hermetic TO-3 case provides decades of proven reliability in industrial and lab-grade supplies.
تجویز کردہ
Hi-Fi Audio Amplifier Output Stage
The MJ2955 is the classic PNP half of a complementary Class AB audio output stage, paired with the 2N3055 NPN on the same TO-3 heatsink. Its 15 A peak collector current and 115 W dissipation comfortably deliver 50-100 W into 8 Ω. The epitaxial-base process yields matched hFE between complementary pairs, minimizing crossover distortion. The TO-3 metal case is bolted to a finned heatsink, providing thermal mass that absorbs music transients without thermal runaway, making it a staple in vintage and modern hi-fi amplifiers.
تجویز کردہ
DC Motor Driver / H-Bridge
The MJ2955 handles the low-side PNP switches in an H-bridge driving DC motors up to 15 A continuous. Its 60 V VCEO tolerates back-EMF spikes from 24 V and 36 V brushed motors, while its 1.52 °C/W θJC sustains heavy stall-current loads with proper heatsinking. Designers typically drive the base via a logic-level MOSFET predriver and add flyback diodes across each transistor. The TO-3 package is rugged against the mechanical vibration common in motor-control enclosures.
تجویز کردہ
Battery Charger Current Source
The MJ2955 is ideal for constant-current battery charging circuits requiring high current capacity up to 15 A for lead-acid and lithium battery packs. Its PNP common-emitter configuration naturally regulates current when the base is held at a fixed voltage, drawing 15 A continuously at 60 V max collector voltage with 1.1 V VCE(sat) minimizing wasted power. The TO-3 chassis-mount case bolts directly to the charger enclosure, providing the 1.52 °C/W thermal path needed for sustained float-charge operation.
تجویز کردہ
Power Inverter / Switch-Mode Output Stage
The MJ2955 finds a role in low-frequency power inverter output stages driving 50/60 Hz transformers from a battery bank. Its 15 A continuous and 60 V rating handle 12 V and 24 V battery systems comfortably, while its hermetic TO-3 case tolerates the thermal cycling of repeated full-load pulses. Designers use the MJ2955 in complementary pairs with the 2N3055 in a push-pull topology, switched at line frequency. The high 115 W dissipation supports multi-hundred-W inverter modules.
تجویز کردہ
Automotive Voltage Regulator / Alternator Control
The MJ2955's 60 V VCEO and 15 A current rating make it well suited to automotive voltage regulator and alternator field-control circuits where load-dump transients up to 60 V are routine. Its hermetic TO-3 case withstands under-hood thermal and vibration stress while delivering 115 W continuous dissipation. Designers wire the MJ2955 as a series-pass element or Darlington predriver in classic electromechanical regulator replacements. Pin compatibility with the 2N3055 enables simple NPN/PNP symmetric regulator designs.
تجویز کردہ
تجویز کردہ پروڈکٹس کا خلاصہ
کے لیے انجینئرنگ ریفرنس ڈیٹا MJ2955 — موازنہ، ڈیزائن رہنمائی، اور تعمیل کی معلومات۔
انتخاب کی گائیڈ
متبادلات کے ساتھ موازنہ
| پیرامیٹر | یہ پروڈکٹ | MJ2955G | 2N2955 | MJ15016 | 2N5880 | 2N6248 | MJ2955 (ST) |
|---|---|---|---|---|---|---|---|
| Brand | onsemi | onsemi | onsemi | onsemi | onsemi | onsemi | STMicroelectronics |
| Package | TO-3 (TO-204-3) | TO-3 (TO-204-3) - same | TO-3 (TO-204-3) - same | TO-3 (TO-204-3) - same | TO-3 (TO-204-3) - same | TO-3 (TO-204-3) - same | TO-3 (TO-204-3) - same |
| VCEO (V) | 60 | 60 | 60 | 120 | 60 | 110 | 60 |
| Continuous IC (A) | 15 | 15 | 15 | 15 | 25 | 13 | 15 |
| Power Dissipation (W) | 115 | 115 | 115 | 150 | 200 | 125 | 115 |
| θJC (°C/W) | 1.52 | 1.52 | 1.52 | 1.0 | 0.875 | 1.4 | 1.52 |
| Polarity | PNP | PNP | PNP | PNP | PNP | PNP | PNP |
| RoHS / Lead-free | Non-RoHS (SnPb) | RoHS (Pb-free) | Non-RoHS | RoHS (Pb-free) | RoHS (Pb-free) | Non-RoHS | RoHS (Pb-free) |
اہم امتیازی خصوصیات
- Industry-standard TO-3 metal-case PNP complement of 2N3055 (بمقابلہ2N3055)
- Lowest-cost RoHS drop-in option available as MJ2955G (بمقابلہMJ2955 (SnPb))
- Higher-current TO-3 upgrade path within onsemi family (بمقابلہ2N5880)
ڈیزائن نوٹس
Estimated: at IC=10 A and VCE=4 V (linear regulator), the MJ2955 dissipates roughly 40 W. With θJC = 1.52 °C/W and a 25 °C case temperature, the junction rises to about 86 °C. Always mount the TO-3 case to a heatsink sized for the maximum continuous dissipation; a bare TO-3 at 25 °C ambient can only handle ~3 W. Use thermal compound and a torque wrench to 0.6-0.8 N·m on the mounting screws to avoid cracking the case.
The TO-3 case is electrically tied to the collector. For chassis-mount applications where the case must float, isolate the transistor with a mica or silicone washer and a nylon shoulder washer on the mounting screw. For grounded-case designs, mount the TO-3 directly to a grounded heatsink for lowest thermal resistance. Keep base and emitter leads short to minimize switching transients in audio applications.
Never substitute the 2N3055 (NPN) for the MJ2955 (PNP) - they are complementary, not interchangeable. Exceeding the 60 V VCEO with inductive kickback (relays, motors) will destroy the part; always clamp with flyback diodes. The 7 A base current rating is absolute - exceeding it destroys the bond wires. Keep VCE(sat) derating in mind: 1.1 V at 15 A means 16.5 W wasted even in saturation.
تعمیل کی معلومات
Standard MJ2955 uses SnPb finish (non-RoHS); choose MJ2955G (Pb-free) for RoHS-compliant end products. Not AEC-Q100 qualified - this is a chassis-mount part for industrial/consumer, not automotive-grade.
