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onsemi TIP31G
- Part No.:
- TIP31G
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-220-3
- Datasheet:
-
TIP31G.pdf
- Description:
- TRANS NPN 40V 3A TO-220
- Quantity:
- Payment:
- Shipping:
Inventory:276
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Product details
Overview
TIP31G from onsemi is an NPN silicon power transistor in TO−220 package, rated for 40 VCEO, 3.0 A continuous collector current, and 40 W power dissipation at TC = 25°C. It serves as a general-purpose amplifier and switching device in DC motor drivers, linear power supplies, and relay interface circuits.
For engineers reviewing the TIP31G datasheet, pinout, applications, or equivalent options, key selection considerations include its 40 V breakdown rating, 3.0 A IC capability, thermal resistance of 3.125 °C/W (junction-to-case), Pb-free TO−220 packaging, and suitability for medium-power linear and switching roles where cost-effective discrete gain and ruggedness are required.
Technical Context
The TIP31G operates as a bipolar junction transistor with fixed NPN polarity and base-controlled current amplification. Its DC current gain (hFE) ranges from 25 to 50 at IC = 1.0 A and VCE = 4.0 V, and it exhibits a current-gain–bandwidth product (fT) of 3.0 MHz under specified test conditions.
It supports unclamped inductive load energy handling up to 32 mJ (IC = 1.8 A, L = 20 mH, VCC = 10 V), and features a maximum VBE(on) of 1.8 V at IC = 3.0 A - confirming its use in moderate-speed, medium-current drive applications without requiring ultra-low saturation voltage.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 40 Vdc - maximum safe collector-emitter voltage before breakdown in open-base configuration |
| IC (continuous) | 3.0 Adc - usable steady-state output current with adequate heatsinking at TC = 25°C |
| PD @ TC = 25°C | 40 W - total power dissipation limit when case temperature is maintained at 25°C |
| RJC | 3.125 °C/W - thermal resistance from junction to case, critical for heatsink sizing |
| hFE (min) | 25 - minimum DC current gain at IC = 1.0 A, VCE = 4.0 V, enabling predictable base drive design |
| VCE(sat) | 1.2 Vdc max - collector-emitter saturation voltage at IC = 3.0 A, IB = 375 mA, defining conduction loss |
| fT | 3.0 MHz - current-gain–bandwidth product indicating usable frequency range for small-signal amplification |
Pinout & Package
Package: TO−220−3 (Case 221A), 10.10 × 15.12 × 4.45 mm, 2.54 mm pin pitch, Pb-free, with pins arranged in Style 1: Pin 1 = Base, Pin 2 = Collector, Pin 3 = Emitter, Pin 4 = Collector (dual-collector configuration).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Pin 1 | Base | Control terminal; requires ~375 mA base current to saturate at 3.0 A collector load |
| Pin 2 | Collector | Main high-side current path; electrically tied to metal tab for thermal and electrical connection |
| Pin 3 | Emitter | Reference/return path for collector current; common connection point in emitter-follower or grounded-emitter topologies |
| Pin 4 | Collector | Second collector terminal - internally connected to Pin 2, providing redundant current path and mechanical stability |
Key Features
| Feature | Design Value |
|---|---|
| High current gain–bandwidth product | 3.0 MHz fT enables stable audio-frequency amplification and fast switching up to ~100 kHz with proper drive |
| TO−220 mechanical robustness | Integral metal tab allows direct mounting to heatsinks with low thermal impedance (RJC = 3.125 °C/W) |
| Unclamped inductive switching capability | Rated for 32 mJ energy absorption in inductive turn-off events (e.g., relay coils, solenoids) |
| Pb-free and RoHS-compliant construction | Meets environmental compliance requirements for industrial and consumer end equipment without lead-based solder concerns |
| Wide operating junction temperature | –65°C to +150°C range supports deployment in automotive under-hood, industrial control, and outdoor power systems |
Applications
| DC Motor Driver Stage | Linear Power Supply Pass Element |
|---|---|
|
Use Scenario: Driving 12 V, 2 A brushed DC motors in industrial actuators with PWM-based speed control. IC Role / Device Role / Timing Role: NPN power switch operating in saturation and cutoff regions; handles bidirectional current during freewheeling via external flyback diode. Use Value: 40 V VCEO margin accommodates back-EMF spikes; 3.0 A IC rating ensures headroom for stall currents; TO−220 tab enables bolt-down heatsinking. |
Use Scenario: Series pass transistor in adjustable 0–30 V, 2 A bench power supply with op-amp error amplifier feedback. IC Role / Device Role / Timing Role: Linear regulator element dissipating up to 25 W under worst-case dropout (e.g., 30 V input → 5 V output @ 2 A). Use Value: 40 W PD @ TC = 25°C and RJC = 3.125 °C/W allow effective thermal management with modest heatsinks; hFE ≥ 25 simplifies base drive design. |
| Relay Interface Circuit | Audio Output Stage (Class-A) |
|
Use Scenario: Controlling 24 V, 500 mA industrial relays from microcontroller GPIO pins via optocoupler-isolated base drive. IC Role / Device Role / Timing Role: Medium-speed digital switch turning relay coil on/off with <15 ns turn-off time and <7 ns turn-on time. Use Value: Low VCE(sat) (≤1.2 V) minimizes coil voltage drop; 32 mJ unclamped inductive energy rating protects against relay coil flyback stress without snubber. |
Use Scenario: Single-ended Class-A audio output stage delivering up to 1 W into 8 Ω speaker loads in low-noise instrumentation amplifiers. IC Role / Device Role / Timing Role: Linear amplifying device biased in active region with fT = 3.0 MHz supporting full audio bandwidth (20 Hz–20 kHz) with minimal phase shift. Use Value: hFE consistency across IC = 0.1–3.0 A enables stable biasing; low VBE(on) variation (<±0.2 V) improves thermal tracking in quiescent current setting. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar NPN power transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MJD31C | Same TO−220 package, but SMD-compatible variant; VCEO = 100 V, IC = 3.0 A, hFE min = 15 at IC = 2.0 A | Higher voltage rating suits 48 V bus systems; lower hFE demands stronger base drive | Select MJD31C when >40 V system voltage or surface-mount assembly is required; not pin-compatible due to different leadform. |
| TIP31C | Same family, higher-voltage variant: VCEO = 100 V, identical TO−220 package and pinout, hFE min = 10 at IC = 3.0 A | Enables use in 72 V or 96 V battery-powered equipment; reduced gain at high current affects base resistor sizing | Choose TIP31C only if 100 V VCEO is mandatory; otherwise TIP31G offers better gain and lower VCE(sat) at 40 V systems. |
Compared with MJD31C and TIP31C, the TIP31G provides optimal balance of gain, saturation voltage, and thermal performance for 12–40 V systems - making it preferable where board space, base drive simplicity, and conduction efficiency outweigh need for higher voltage margin.
Availability
TIP31G is available at Aetrix Electronics and suitable for DC motor control, linear power regulation, relay interfacing, and Class-A audio output stages requiring stable component supply and legacy-design continuity.
Supply support for TIP31G 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 management, analog, sensors, and logic devices for automotive, industrial, and consumer markets.
The TIP31G belongs to onsemi's legacy plastic power transistor family designed for cost-sensitive, medium-power linear and switching applications where ruggedness, manufacturability, and thermal reliability are prioritized over ultra-high frequency or ultra-low loss.
FAQ
What is the maximum collector-emitter voltage rating for the TIP31G?
The TIP31G has a maximum collector-emitter voltage (VCEO) rating of 40 Vdc, verified under test condition IC = 30 mA and IB = 0. This rating defines the upper limit for safe operation in the active or cutoff region and must not be exceeded even transiently without additional clamping protection. The TIP31G datasheet confirms this value in both Maximum Ratings and OFF Characteristics tables.
Is the TIP31G pin-compatible with other TIP31x variants like TIP31C?
Yes, the TIP31G shares identical TO−220 package outline (Case 221A, Style 1) and pin assignment (Pin 1 = Base, Pin 2 = Collector, Pin 3 = Emitter, Pin 4 = Collector) with TIP31A, TIP31B, and TIP31C. All variants maintain the same mechanical footprint and terminal configuration, enabling direct physical replacement - though electrical differences (e.g., VCEO, hFE) require circuit validation.
What is the typical DC current gain (hFE) of the TIP31G at 3.0 A collector current?
The TIP31G specifies a minimum hFE of 10 at IC = 3.0 A and VCE = 4.0 V, per the Electrical Characteristics table. While typical curves (Figure 8) show hFE ≈ 20–30 under those conditions, design must use the guaranteed minimum of 10 to ensure reliable base drive across process and temperature extremes - meaning a 300 mA base current is required for full 3.0 A saturation.
Can the TIP31G be used in switching applications with inductive loads?
Yes, the TIP31G is explicitly rated for unclamped inductive load energy of 32 mJ (IC = 1.8 A, L = 20 mH, VCC = 10 V), as stated in the Maximum Ratings table. This makes it suitable for relay, solenoid, and small DC motor switching where flyback energy must be absorbed internally. However, repeated operation near this limit requires careful thermal management and derating per Figure 1.
Does the TIP31G have RoHS-compliant packaging?
Yes, the "G" suffix in TIP31G denotes a Pb-free, RoHS-compliant TO−220 package, confirmed in the Features section and Marking Diagram of the official onsemi datasheet (Publication Order Number TIP31A/D, Rev. 17). The device meets EU Directive 2011/65/EU and contains no intentionally added lead, mercury, cadmium, hexavalent chromium, PBB, or PBDE.
TIP31G 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):
- 40 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:
- -65°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- TO-220
TIP31G FAQ
1.How can I place an order for TIP31G through Aetrix?
Please submit a Request for Quotation (RFQ) for TIP31G 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 TIP31G reliable?
The price and inventory of TIP31G are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TIP31G is usually 5 days.
3.What payment methods are accepted for TIP31G?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TIP31G transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TIP31G?
TIP31G orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TIP31G 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 TIP31G?
For technical support, including TIP31G datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TIP31G requirements.
6.How does Aetrix verify that TIP31G is sourced from the original manufacturer or authorized distributors?
All TIP31G 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 TIP31G meets industry standards.
7.What is the process for return or replacement of TIP31G?
All TIP31G units undergo pre-shipment inspection (PSI). If there is an issue with TIP31G, 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 TIP31G part is unused and in its original packaging.
Return procedure for TIP31G:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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