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onsemi TIP31CTU
- Part No.:
- TIP31CTU
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-220-3
- Datasheet:
-
TIP31CTU.pdf
- Description:
- TRANS NPN 100V 3A TO-220-3
- Quantity:
- Payment:
- Shipping:
Inventory:2,800
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Product details
Overview
TIP31CTU from onsemi is a complementary PNP silicon power transistor in TO−220 package, rated for 100 VCEO, 1.0 A continuous collector current, and 30 W total power dissipation at TC = 25°C. It serves as a general-purpose switching and linear amplifier device in DC-DC converters, relay drivers, and motor control stages.
For engineers reviewing the TIP31CTU datasheet, pinout, applications, or equivalent options, key selection criteria include VCEO = 100 V, IC = 1.0 A, hFE ≥ 15 (at IC = 1.0 A), VCE(sat) ≤ 0.7 V, and thermal resistance RJC = 4.167 °C/W - all critical for thermal management and saturation performance in high-current switching designs.
Technical Context
The TIP31CTU operates as a medium-power PNP bipolar junction transistor with fixed gain structure optimized for robust switching and analog amplification. Its safe operating area (SOA) is defined up to 100 V and 1.0 A under DC conditions, with second-breakdown-limited pulse capability validated at 1 ms and 5 ms durations.
It features a low VBE(on) of ≤1.3 V at IC = 1.0 A and exhibits fT = 3.0 MHz, supporting audio-frequency and low-speed digital switching applications. The device is Pb-free, RoHS-compliant, and qualified for operation across −65°C to +150°C junction temperature range.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 100 V - Maximum collector-emitter voltage before breakdown; enables use in 80 V rail systems with margin. |
| IC (continuous) | 1.0 A - Sustained load current capacity; supports relay coils, small solenoids, and fan drivers. |
| PD @ TC = 25°C | 30 W - Power handling with heatsink; requires thermal interface design for >10 W continuous operation. |
| hFE | 15–75 - DC current gain range at IC = 0.2–1.0 A; ensures reliable base drive sizing in saturated switch mode. |
| VCE(sat) | ≤0.7 V @ IC = 1.0 A, IB = 125 mA - Low saturation voltage reduces conduction loss and self-heating. |
| RJC | 4.167 °C/W - Junction-to-case thermal resistance; defines minimum heatsink requirement for thermal stability. |
Pinout & Package
Package: TO−220 (Case 221A, Style 1), through-hole, single-ended heatsink tab (pin 2 & 4 are collector and electrically connected).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base | Current-controlled input terminal; requires ≥125 mA base drive for full saturation at 1.0 A collector load. |
| 2 & 4 | Collector | High-side connection point; electrically common pins; mounted to heatsink for thermal path and electrical reference. |
| 3 | Emitter | Common emitter node; tied to system ground or negative rail in PNP high-side switch configurations. |
Key Features
| Feature | Design Value |
|---|---|
| Pb-free / RoHS compliant | Meets global environmental regulations; compatible with lead-free reflow and wave soldering processes. |
| Unclamped inductive energy rating | 32 mJ (tested at LC = 20 mH, VCC = 10 V, IC = 1.8 A); supports relay/solenoid snubberless switching. |
| Wide operating temperature range | −65°C to +150°C junction; suitable for industrial and automotive under-hood environments without derating. |
| TO−220 mechanical standardization | Compatible with industry-standard heatsinks and mounting hardware; simplifies thermal design reuse. |
Applications
| DC Motor Control | Relay Driver Circuit |
|---|---|
|
Use Scenario: Driving 24 V brushed DC motors in industrial actuators with PWM duty cycling up to 5 kHz. IC Role / Device Role / Timing Role: PNP high-side switch controlling motor supply rail; handles peak currents up to 1.8 A during startup. Use Value: VCEO = 100 V provides headroom against back-EMF spikes; RJC = 4.167 °C/W enables stable operation with minimal heatsinking. |
Use Scenario: Activating 12 V/24 V electromagnetic relays in PLC output modules and HVAC controllers. IC Role / Device Role / Timing Role: Saturated PNP switch sourcing current to relay coil; driven by microcontroller GPIO via base resistor. Use Value: VCE(sat) ≤ 0.7 V minimizes coil voltage drop; unclamped energy rating of 32 mJ eliminates need for external flyback diode in many cases. |
| Linear Voltage Regulator Pass Element | Power Supply Foldback Protection |
|
Use Scenario: Acting as series pass transistor in adjustable 0–30 V, 1 A bench power supplies. IC Role / Device Role / Timing Role: Linear regulator pass element dissipating up to 20 W under worst-case dropout conditions. Use Value: SOA curve validated to 100 V × 1 A DC supports safe operation at 30 V × 1 A; RJC enables direct heatsink mounting. |
Use Scenario: Implementing current-limit foldback in dual-rail lab power supplies using emitter-sensing feedback. IC Role / Device Role / Timing Role: Current-sense controlled PNP switch that reduces output current during overloads to protect downstream circuitry. Use Value: Tight hFE consistency (min 15 at 1 A) ensures predictable foldback threshold; low VBE(on) improves sensing accuracy. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar PNP power transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MJD31C | Surface-mount DPAK package (vs. TO−220); same VCEO = 100 V, IC = 1.0 A, but lower PD = 20 W @ TC = 25°C. | Preferred for space-constrained PCBs; requires thermal pad layout and reflow profile optimization. | Select MJD31C when board real estate is limited and automated assembly is required; verify heatsink interface for equivalent thermal performance. |
| TIP32C | Same TO−220 package, identical VCEO, IC, and hFE specs; differs only in manufacturer marking and minor process revision (ON Semi vs. STMicroelectronics). | No functional or layout change needed; used interchangeably in legacy designs with same thermal and drive requirements. | Choose TIP32C if sourcing diversification or long-term availability from alternate suppliers is prioritized; pinout and SOA match exactly. |
Compared with MJD31C and TIP32C, the TIP31CTU offers higher power dissipation (30 W vs. 20 W) in through-hole format, making it preferable for prototyping, repair, and thermally demanding linear applications where manual heatsink attachment is acceptable.
Availability
TIP31CTU is available at Aetrix Electronics and suitable for DC motor control, relay driver circuits, linear voltage regulator pass elements, and power supply foldback protection requiring stable component supply and long-life industrial availability.
Supply support for TIP31CTU 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
onsemi (formerly ON Semiconductor) is a global semiconductor supplier specializing in energy-efficient power, analog, sensor, and connectivity solutions for automotive, industrial, cloud, and consumer markets.
The TIP31CTU belongs to onsemi's legacy silicon power transistor family designed for cost-sensitive, high-reliability general-purpose switching and amplification - emphasizing ruggedness, wide temperature operation, and manufacturability in TO−220 packaging.
FAQ
What is the maximum collector-emitter voltage rating for the TIP31CTU?
The TIP31CTU has a maximum collector-emitter sustaining voltage (VCEO(sus)) of 100 Vdc at IC = 30 mA and IB = 0. This rating ensures safe operation in 80 V nominal systems with sufficient margin against transients. Exceeding this voltage risks avalanche breakdown and permanent damage. The TIP31CTU must not be operated beyond its specified VCEO limit under any condition, including inductive switching events unless properly clamped.
Is the TIP31CTU suitable for linear regulator applications?
Yes, the TIP31CTU is commonly used as a series pass transistor in adjustable linear regulators due to its 30 W power dissipation capability at TC = 25°C and validated SOA up to 100 V × 1 A DC. Its VCE(sat) ≤ 0.7 V and hFE ≥ 15 at 1 A ensure predictable base drive and low dropout loss. Thermal design must account for RJC = 4.167 °C/W and ambient case temperature to avoid exceeding TJ = 150°C.
Does the TIP31CTU require a heatsink in switching applications?
A heatsink is required for the TIP31CTU in any application where power dissipation exceeds ~2–3 W continuously, due to its RJA = 62.5 °C/W (no heatsink). Even at 1.0 A and VCE = 0.7 V, conduction loss reaches 0.7 W - but switching losses and ambient temperature rise necessitate heatsinking above 10% duty cycle or >50°C ambient. The TO−220 tab (pins 2 & 4) must be mechanically and thermally attached to a heatsink for reliable operation above 5 W.
What is the base-emitter on voltage specification for the TIP31CTU?
The TIP31CTU has a maximum base-emitter on voltage (VBE(on)) of 1.3 Vdc at IC = 1.0 A and VCE = 4.0 Vdc. This value determines the minimum base drive voltage needed for saturation and influences base resistor selection. At lower collector currents (e.g., 0.2 A), VBE(on) drops to ~1.1 V. Accurate VBE(on) knowledge is essential for calculating base current and ensuring full turn-on in switching designs.
Can the TIP31CTU replace the TIP32C in an existing design?
The TIP31CTU and TIP32C share identical electrical specifications (VCEO = 100 V, IC = 1.0 A, hFE, VCE(sat), RJC) and TO−220 pinout (base-collector-emitter-collector), making them functionally interchangeable in most applications. However, TIP32C is manufactured by STMicroelectronics, while TIP31CTU is from onsemi - so qualification testing for long-term reliability and thermal behavior under specific load profiles is recommended before full substitution in production.
TIP31CTU Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-220-3
- Packaging:
- Tube
- Product Status:
- Obsolete
- Transistor Type:
- NPN
- Current - Collector (Ic) (Max):
- 3 A
- Voltage - Collector Emitter Breakdown (Max):
- 100 V
- Vce Saturation (Max) @ Ib, Ic:
- 1.2V @ 375mA, 3A
- Current - Collector Cutoff (Max):
- 300µA
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 10 @ 3A, 4V
- Power - Max:
- 2 W
- Frequency - Transition:
- 3MHz
- Operating Temperature:
- 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- TO-220-3
TIP31CTU FAQ
1.How can I place an order for TIP31CTU through Aetrix?
Please submit a Request for Quotation (RFQ) for TIP31CTU 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 TIP31CTU reliable?
The price and inventory of TIP31CTU are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TIP31CTU is usually 5 days.
3.What payment methods are accepted for TIP31CTU?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TIP31CTU transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TIP31CTU?
TIP31CTU orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TIP31CTU 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 TIP31CTU?
For technical support, including TIP31CTU datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TIP31CTU requirements.
6.How does Aetrix verify that TIP31CTU is sourced from the original manufacturer or authorized distributors?
All TIP31CTU 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 TIP31CTU meets industry standards.
7.What is the process for return or replacement of TIP31CTU?
All TIP31CTU units undergo pre-shipment inspection (PSI). If there is an issue with TIP31CTU, 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 TIP31CTU part is unused and in its original packaging.
Return procedure for TIP31CTU:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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