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onsemi MJE171STU
- Part No.:
- MJE171STU
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-225AA, TO-126-3
- Datasheet:
-
MJE171STU.pdf
- Description:
- TRANS PNP 60V 3A TO-126-3
- Quantity:
- Payment:
- Shipping:
Inventory:6,076
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Product details
Overview
MJE171STU from ON Semiconductor is a PNP epitaxial silicon transistor designed for low-power audio amplification and high-speed switching applications. It features a collector-emitter breakdown voltage of –60 V, DC current gain (hFE) of 30–250 at –500 mA, saturation voltage (VCE(sat)) as low as –0.3 V at –500 mA/–50 mA drive, and operates in TO-126 package with 3-pin emitter-collector-base configuration.
For engineers reviewing the MJE171STU datasheet, pinout, applications, or equivalent options, key selection considerations include its –60 V VCEO, –3 A continuous collector current capability, thermal performance up to 150 °C junction temperature, and suitability for linear amplifier stages and relay/motor driver switching circuits requiring robust PNP gain and saturation behavior.
Technical Context
The MJE171STU is a medium-power PNP bipolar junction transistor optimized for linear and switching operation in industrial and consumer electronics. Its hFE range (30–250) supports both high-gain small-signal amplification and stable current-controlled switching, while its fT of 50 MHz enables use in audio-frequency signal paths and fast digital edge control.
Thermal design is constrained by 12.5 W collector dissipation at TC = 25 °C and only 1.5 W at ambient (TA = 25 °C), indicating mandatory heatsinking for sustained >500 mA loads. The device's Cob of 50 pF at –10 V VCB and turn-off time (tF + tSTG) under 100 ns support reliable operation in pulse-width modulation and Class-B amplifier output stages.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | –60 V - Maximum safe collector-emitter voltage before breakdown; defines usable supply rail headroom in PNP switch or amplifier configurations. |
| IC (DC) | –3 A - Continuous collector current rating; sets maximum steady-state load current without forced cooling. |
| hFE | 30–250 @ –1 V VCE, –100 mA to –1.5 A - Gain variation across operating range; critical for bias stability in amplifier designs. |
| VCE(sat) | –0.3 V @ –500 mA / –50 mA - Low saturation voltage minimizes power loss and heating in switching applications. |
| fT | 50 MHz - Current gain bandwidth product; confirms suitability for audio-band amplification and fast-switching control signals. |
| Cob | 50 pF @ –10 V VCB - Output capacitance affects high-frequency response and switching speed in inductive load drivers. |
| PC (TC=25°C) | 12.5 W - Maximum power dissipation with case temperature held at 25 °C; requires mechanical heatsink interface for full rating. |
Pinout & Package
Package: TO-126, through-hole, 3-lead plastic power package with metal tab connected to collector for thermal and electrical grounding. Dimensions: 16.10 × 13.06 × 4.2 mm (L × W × H), lead pitch 2.28 mm.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Emitter) | Current source terminal for PNP operation | Connected to higher potential (e.g., VCC) in common-emitter switches; base drive referenced to this node. |
| 2 (Collector) | Current sink terminal; electrically tied to metal tab | Must be thermally coupled to heatsink; polarity reversal relative to NPN devices requires careful PCB layout. |
| 3 (Base) | Control input for minority-carrier injection | Requires current-limited drive (max IB = –1 A); VBE(on) ≈ –1.2 V ensures predictable turn-on threshold. |
Key Features
| Feature | Design Value |
|---|---|
| High VCEO rating | –60 V enables use in 48 V industrial control rails and legacy ±15 V/±24 V analog systems without derating. |
| Low VCE(sat) | –0.3 V at moderate current reduces conduction loss by >40% vs. standard PNP transistors, improving efficiency in relay drivers. |
| Wide hFE range | 30–250 supports both precision biasing (high hFE) and robust overdrive (low hFE) in production-grade designs. |
| TO-126 mechanical compatibility | Standard footprint allows drop-in replacement of legacy PNP power transistors (e.g., MJE15034, BD139 variants) with identical mounting. |
| 150 °C max junction temperature | Enables operation in sealed enclosures or high-ambient environments (e.g., automotive under-hood, industrial motor drives) with proper thermal management. |
Applications
| Audio Power Amplifier Stage | DC Motor Direction Control |
|---|---|
|
Use Scenario: Complementary Class-B output stage in low-voltage audio amplifiers (e.g., 12 V supply). IC Role / Device Role / Timing Role: PNP output transistor delivering negative half-cycle current to speaker load. Use Value: VCE(sat) ≤ –0.3 V minimizes crossover distortion and thermal rise during continuous sine-wave output at 1–2 W. |
Use Scenario: H-bridge upper-leg switch controlling bidirectional 24 V DC motor rotation. IC Role / Device Role / Timing Role: High-side PNP switch enabling current flow from supply to motor winding. Use Value: –60 V VCEO and –3 A IC support 24 V motors with inductive kickback suppression and stall-current tolerance. |
| Relay Driver Circuit | Linear Voltage Regulator Pass Element |
|
Use Scenario: Solid-state replacement for electromechanical relays in PLC I/O modules. IC Role / Device Role / Timing Role: Switching element driving 12–24 V coil loads with opto-isolated base control. Use Value: Fast turn-off (tF < 100 ns) prevents contact bounce artifacts; Cob = 50 pF avoids EMI coupling into adjacent logic lines. |
Use Scenario: Series pass transistor in adjustable linear regulators for sensitive analog subsystems. IC Role / Device Role / Timing Role: Current-regulating element dissipating excess voltage between unregulated input and regulated output. Use Value: hFE ≥ 30 at –1.5 A ensures stable loop gain with minimal base drive current, reducing quiescent power in low-noise LDO designs. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar PNP power transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MJE172STU | Higher VCEO (–80 V) and VCBO (–100 V); otherwise identical pinout, gain, and saturation characteristics. | Better suited for 48–60 V bus systems where MJE171STU would operate near voltage limit. | Select MJE172STU when system transient voltage exceeds 50 V or long-term reliability at >80% VCEO rating is required. |
| BD140 | Lower VCEO (–80 V), same TO-126 package, but hFE min = 40 (vs. 30 for MJE171STU); VCE(sat) slightly higher (–0.5 V typical). | Common in European consumer audio designs; less margin in low-VCE switching but tighter hFE distribution. | Choose BD140 if tighter gain binning is needed and voltage stress remains below 50 V; verify thermal derating due to lower PC (12.5 W same, but lower fT). |
Compared with MJE171STU, MJE172STU offers extended voltage headroom without layout change, while BD140 trades slight saturation penalty for improved hFE consistency-making MJE171STU optimal for cost-sensitive 24–48 V industrial switching where its –60 V rating provides balanced safety margin and efficiency.
Availability
MJE171STU is available at Aetrix Electronics and suitable for industrial motor control, audio amplifier manufacturing, and programmable logic controller (PLC) I/O module production requiring stable component supply and long-term obsolescence management.
Supply support for MJE171STU includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
ON Semiconductor is a global semiconductor manufacturer specializing in energy-efficient power, analog, sensor, and connectivity solutions for automotive, industrial, cloud, and consumer markets.
The MJE171STU belongs to ON Semiconductor's legacy power bipolar transistor family, originally developed by Fairchild Semiconductor for robust, cost-effective linear and switching applications in industrial controls and audio systems.
FAQ
What is the maximum continuous collector current rating for the MJE171STU?
The MJE171STU has a rated DC collector current (IC) of –3 A at TC = 25 °C. This rating assumes adequate heatsinking; at ambient temperature (TA = 25 °C) without heatsink, the safe continuous current drops to approximately –0.5 A due to its 1.5 W ambient-rated power dissipation. Always verify thermal design using the published SOA curves in the MJE171STU datasheet.
Is the MJE171STU pin-compatible with other TO-126 PNP transistors like the BD140?
Yes, the MJE171STU uses the standard TO-126 package with identical pinout (1: Emitter, 2: Collector, 3: Base), making it mechanically and electrically pin-compatible with BD140, MJE15035, and similar TO-126 PNP transistors. However, differences in VCEO, hFE, and VCE(sat) require circuit validation before substitution-especially in high-voltage or precision-bias applications.
What is the typical base-emitter on voltage (VBE(on)) for the MJE171STU?
The MJE171STU exhibits a typical VBE(on) of –1.2 V at VCE = –1 V and IC = –500 mA. This value is consistent across production lots and forms the basis for calculating required base drive resistance in switching applications. At higher currents (e.g., –3 A), VBE(sat) rises to –2.0 V, which must be accounted for in high-current driver design.
Can the MJE171STU be used in audio amplifier output stages?
Yes, the MJE171STU is explicitly characterized for low-power audio amplifier applications per its datasheet. Its fT of 50 MHz, low VCE(sat), and well-defined hFE curve across –100 mA to –1.5 A make it suitable for Class-B and Class-AB output stages in 12–24 V systems. Thermal stability under continuous sine-wave load should be verified using the published SOA and thermal resistance data for MJE171STU.
Does the MJE171STU have a built-in base-emitter resistor or protection diode?
No, the MJE171STU is a bare-die PNP bipolar transistor with no integrated base resistors or protection diodes. External base current limiting and optional BE clamp diodes must be added per application requirements. This discrete architecture gives designers full control over biasing but requires careful attention to second-breakdown limits and safe operating area boundaries defined in the MJE171STU datasheet.
MJE171STU Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-225AA, TO-126-3
- Packaging:
- Tube
- Product Status:
- Obsolete
- Transistor Type:
- PNP
- Current - Collector (Ic) (Max):
- 3 A
- Voltage - Collector Emitter Breakdown (Max):
- 60 V
- Vce Saturation (Max) @ Ib, Ic:
- 1.7V @ 600mA, 3A
- Current - Collector Cutoff (Max):
- 100nA (ICBO)
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 50 @ 100mA, 1V
- Power - Max:
- 1.5 W
- Frequency - Transition:
- 50MHz
- Operating Temperature:
- 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- TO-126-3
MJE171STU FAQ
1.How can I place an order for MJE171STU through Aetrix?
Please submit a Request for Quotation (RFQ) for MJE171STU on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for MJE171STU reliable?
The price and inventory of MJE171STU are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MJE171STU is usually 5 days.
3.What payment methods are accepted for MJE171STU?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MJE171STU transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MJE171STU?
MJE171STU orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MJE171STU order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for MJE171STU?
For technical support, including MJE171STU datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MJE171STU requirements.
6.How does Aetrix verify that MJE171STU is sourced from the original manufacturer or authorized distributors?
All MJE171STU products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that MJE171STU meets industry standards.
7.What is the process for return or replacement of MJE171STU?
All MJE171STU units undergo pre-shipment inspection (PSI). If there is an issue with MJE171STU, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The MJE171STU part is unused and in its original packaging.
Return procedure for MJE171STU:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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