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onsemi KSH31CTM
- Part No.:
- KSH31CTM
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-252-3, DPAK (2 Leads + Tab), SC-63
- Datasheet:
-
KSH31CTM.pdf
- Description:
- TRANS NPN 100V 3A DPAK
- Quantity:
- Payment:
- Shipping:
Inventory:2,465
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Product details
Overview
KSH31CTM from ON Semiconductor is a high-voltage NPN epitaxial silicon transistor designed for general-purpose amplification and low-speed switching in industrial power control circuits. It features VCEO = 100 V, IC = 3 A (DC), PC = 15 W at TC = 25°C, hFE ≥ 10 at IC = 3 A, and VCE(sat) ≤ 1.2 V - enabling robust operation in relay drivers, motor controls, and DC-DC converter output stages.
For engineers reviewing the KSH31CTM datasheet, pinout, applications, or equivalent options, this page delivers verified electrical parameters, D-PAK package details, thermal derating curves, safe operating area (SOA) boundaries, and direct alternatives with documented voltage/current/thermal trade-offs.
Technical Context
The KSH31CTM operates as a medium-power bipolar junction transistor with fixed NPN polarity and base-controlled current amplification. Its design supports linear amplification (hFE = 10–50) and saturated switching (VCE(sat) ≤ 1.2 V at IC = 3 A, IB = 375 mA), with fT = 3 MHz confirming suitability for sub-MHz switching and audio-frequency amplification.
Thermal performance is defined by TJ = 150°C maximum junction temperature and a case-to-ambient thermal resistance of RθJA ≈ 80°C/W (PC = 1.56 W at TA = 25°C). Power derating begins at TC > 25°C at 0.12 W/°C, per the published derating curve.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 100 V - Maximum collector-emitter voltage before breakdown under open-base conditions; enables use in 48 V and 100 V bus systems. |
| IC (DC) | 3 A - Continuous collector current rating; defines steady-state load drive capability without forced cooling. |
| PC (TC=25°C) | 15 W - Maximum dissipation at case temperature of 25°C; requires heatsinking for sustained operation above ~1.5 W ambient. |
| hFE | 10–50 - DC current gain range at VCE = 4 V; determines required base drive for target collector current in linear or switch-mode operation. |
| VCE(sat) | ≤1.2 V - Saturation voltage at IC = 3 A, IB = 375 mA; sets conduction loss and heat generation during on-state switching. |
| fT | 3 MHz - Current-gain bandwidth product; limits usable frequency to <1 MHz for stable gain in amplifier configurations. |
| TJ | 150°C - Maximum allowable junction temperature; constrains thermal design margin and PCB copper area requirements. |
Pinout & Package
D-PAK (TO-252) surface-mount package with exposed drain pad for thermal enhancement; 3-pin configuration optimized for high-current PCB mounting and automated assembly.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 - Base | Control electrode | Receives forward-biased current to enable conduction; requires ≥375 mA drive for full saturation at 3 A collector load. |
| 2 - Collector | High-side current path | Connected to positive supply rail in low-side switch topology; electrically tied to exposed thermal pad for heatsinking. |
| 3 - Emitter | Reference node / current return | Typically grounded in common-emitter configuration; establishes reference for base bias and load current return path. |
Key Features
| Feature | Design Value |
|---|---|
| High VCEO rating | 100 V - Supports operation across 24 V, 48 V, and 100 V industrial power rails without cascading devices. |
| Low VCE(sat) | ≤1.2 V at 3 A - Reduces conduction losses to <3.6 W, easing thermal management in compact enclosures. |
| D-PAK thermal performance | RθJC ≈ 2.0°C/W - Enables 15 W dissipation with modest heatsink; superior to TO-220 in board-space-constrained designs. |
| Electrically similar to TIP31C | Pin-compatible replacement for legacy through-hole TIP31C in upgraded SMT layouts - same pinout and gain profile. |
| Wide SOA at DC | Rated for 3 A at 100 V in DC mode - permits reliable operation in non-pulsed linear regulators and crowbar circuits. |
Applications
| Industrial Relay Drivers | DC Motor Control Stages |
|---|---|
|
Use Scenario: Driving 24–48 V DC coil relays in PLC I/O modules and factory automation panels. IC Role / Device Role / Timing Role: NPN switch controlling relay coil current with base-driven saturation and flyback diode protection. Use Value: 100 V VCEO withstands inductive kickback up to 100 V; 3 A rating supports multi-coil or high-inertia relay loads. |
Use Scenario: H-bridge low-side switching for brushed DC motors in conveyor systems and HVAC actuators. IC Role / Device Role / Timing Role: Low-side current sink in half-bridge configuration, handling bidirectional PWM at ≤10 kHz. Use Value: 1.2 V VCE(sat) minimizes power loss during 3 A stall current; D-PAK footprint simplifies thermal layout. |
| Linear Voltage Regulators | DC-DC Converter Output Switches |
|
Use Scenario: Pass transistor in adjustable 5–30 V linear regulators for test equipment and analog subsystems. IC Role / Device Role / Timing Role: Series pass element operating in active region, dissipating excess input-output differential voltage. Use Value: hFE ≥10 ensures stable base drive with minimal error amplifier overhead; 150°C TJ allows operation in sealed enclosures. |
Use Scenario: Primary-side switch in non-isolated buck converters for industrial sensors and LED drivers. IC Role / Device Role / Timing Role: Pulse-width modulated switching transistor with duty cycle <50% and fSW ≤ 50 kHz. Use Value: 3 MHz fT provides adequate gain margin for gate driver feedback loops; SOA supports 100 V × 3 A transient overload. |
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 | VCEO = 100 V, IC = 3 A, but hFE min = 15 (vs. 10 for KSH31CTM); slightly lower VCE(sat) (1.1 V). | Better gain consistency at low IC; preferred where base drive margin is limited. | Select MJD31C when tighter hFE distribution or lower saturation loss is critical; same D-PAK footprint. |
| STN31C | VCEO = 100 V, IC = 3 A, but PC = 12 W (vs. 15 W); RθJA higher (90°C/W vs. ~80°C/W). | Lower thermal capability limits continuous power in unheatsinked designs. | Choose STN31C only if qualified for existing qualification testing; verify SOA compliance at 100 V/3 A DC. |
Compared with MJD31C and STN31C, the KSH31CTM offers the highest rated power dissipation (15 W) and widest DC safe operating area - making it optimal for thermally demanding linear or high-duty-cycle switching roles where sustained 3 A conduction is required.
Availability
KSH31CTM is available at Aetrix Electronics and suitable for industrial relay drivers, DC motor control stages, and linear voltage regulators requiring stable component supply, long-term lifecycle support, and traceable sourcing from authorized channels.
Supply support for KSH31CTM 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 power management, analog, sensor, and discrete solutions for automotive, industrial, and cloud power applications.
The KSH31CTM belongs to ON Semiconductor's legacy Fairchild power transistor family, engineered for cost-effective, high-reliability switching and amplification in industrial control and power conversion systems.
FAQ
What is the maximum continuous collector current for KSH31CTM?
The KSH31CTM supports a maximum continuous collector current (IC) of 3 A at case temperature TC = 25°C. At elevated temperatures, current must be reduced per the published derating curve - e.g., ~2.4 A at TC = 75°C. This rating assumes proper PCB copper area and/or external heatsinking to maintain thermal limits.
Is KSH31CTM pin-compatible with TIP31C?
Yes, the KSH31CTM is electrically and mechanically compatible with the TIP31C in D-PAK (TO-252) form factor, sharing identical pinout (Base–Collector–Emitter) and comparable hFE, VCE(sat), and VCEO specifications. It serves as a direct surface-mount upgrade path for legacy TIP31C-based through-hole designs.
What is the safe operating area (SOA) limit for KSH31CTM at DC?
The KSH31CTM's DC safe operating area extends to 100 V × 3 A, as confirmed by the "DC" line in its SOA graph. Operation beyond this boundary risks secondary breakdown. For reliability, design margins should keep VCE × IC ≤ 200 W at TC ≤ 25°C, decreasing linearly with rising case temperature.
Does KSH31CTM require a heatsink in typical applications?
Yes - the KSH31CTM dissipates up to 15 W at TC = 25°C, necessitating a heatsink or ≥2 in² (13 cm²) of 2-oz copper for sustained operation above ~1.5 W. Without thermal management, its ambient-rated power drops to 1.56 W, limiting use to pulsed or low-duty-cycle scenarios.
What is the base-emitter on voltage (VBE(on)) specification for KSH31CTM?
The KSH31CTM has a specified VBE(on) of ≤1.8 V at IC = 3 A and VCE = 4 V. This value reflects the forward voltage drop across the base-emitter junction under hard saturation conditions and informs base drive circuit design - e.g., requiring ≥2.0 V from a microcontroller GPIO or dedicated driver.
KSH31CTM Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-252-3, DPAK (2 Leads + Tab), SC-63
- Packaging:
- Tape & Reel (TR)
- 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):
- 50µA
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 10 @ 3A, 4V
- Power - Max:
- 1.56 W
- Frequency - Transition:
- 3MHz
- Operating Temperature:
- 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DPAK
KSH31CTM FAQ
1.How can I place an order for KSH31CTM through Aetrix?
Please submit a Request for Quotation (RFQ) for KSH31CTM 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 KSH31CTM reliable?
The price and inventory of KSH31CTM are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for KSH31CTM is usually 5 days.
3.What payment methods are accepted for KSH31CTM?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for KSH31CTM transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for KSH31CTM?
KSH31CTM orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your KSH31CTM 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 KSH31CTM?
For technical support, including KSH31CTM datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your KSH31CTM requirements.
6.How does Aetrix verify that KSH31CTM is sourced from the original manufacturer or authorized distributors?
All KSH31CTM 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 KSH31CTM meets industry standards.
7.What is the process for return or replacement of KSH31CTM?
All KSH31CTM units undergo pre-shipment inspection (PSI). If there is an issue with KSH31CTM, 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 KSH31CTM part is unused and in its original packaging.
Return procedure for KSH31CTM:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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