TIP31C - NPN 100V 3A Power Transistor TO-220 | STMicroelectronics
N.º de pieza: TIP31C ✓ Activo| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $0.72 | $0,72 |
| 10 | $0.58 | $5,80 |
| 100 | $0.46 | $46,00 |
| 500 | $0.39 | $195,00 |
| 1.000 | $0.33 | $330,00 |
TIP31C Descripción general
A BJT power transistor is a three-terminal semiconductor that uses a small base current to control a much larger collector current, making it the workhorse of medium-power amplification and switching. Within the power management hierarchy, the TIP31C sits in the discrete transistor family that spans from small-signal BJTs up to high-current Darlington devices, and it is complemented by the PNP TIP32C for push-pull designs.
Key features include a 100 V VCEO rating that provides ample margin on 48 V-class rails, a 3 A continuous collector current with peak capability up to 5 A per the ST datasheet family rating, a DC current gain (hFE) of at least 10 at 3 A, and a transition frequency of 3 MHz. The base island technology construction lowers saturation voltage and improves switching behavior compared with conventional epitaxial designs.
Technically, the TIP31C uses an epitaxial-base NPN silicon structure optimized for both linear and switching service. Power dissipation is rated at 40 W at a case temperature of 25 C when properly heatsinked (approximately 2 W free-air per distributor listings), so thermal design determines real usable output.
Typical applications include audio amplifier output stages, general-purpose linear regulators, relay and solenoid drivers, motor drivers, and medium-speed power switching circuits.
When designing with the TIP31C, verify the safe operating area at your actual case temperature and drive the base with sufficient current to keep hFE-related saturation losses low; a forced beta of 10 is the usual rule of thumb.
This page synthesizes distributor pricing, drop-in alternatives, pinout details, and practical design notes not found in the manufacturer datasheet alone.
Alternativas directas para TIP31C — mismo encapsulado, compatible pin a pin. Se excluyen las piezas de otro encapsulado que requieren retrabajo de la PCB.
Variantes de esta serie
Modelos de la misma serie compatibles directamente con TIP31C (mismo factor de forma y huella) — difiere en Package.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
TIP31CG
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
TIP32C
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
TIP41C
✅ Sustitución directa✓ En stock
$0.35 / unidad
Ver hoja de datos →TIP31A
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
TIP31C
✅ Sustitución directa✓ En stock
$0.33 / unidad
Ver hoja de datos →2N6122
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
BDT31C
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
MJE340K
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
TIP31C Valores máximos y características eléctricas
| Tipo de transistor | NPN Bipolar Junction Transistor (BJT) |
| Tensión colector-emisor (Vceo) | 100 V |
| Collector Current (IC Continuous) | 3 A |
| Disipación de potencia (TC=25°C) | 40 W |
| Power Dissipation (Free Air) | 2 W |
| Frecuencia de transición (ft) | 3 MHz |
| Encapsulado | TO-220 (through-hole) |
| Tipo de montaje | Through Hole |
| Technology | Base Island Technology |
| Polarity | NPN |
| Complementary Part | TIP32C (PNP) |
| Applications | Audio, power linear and switching |
| Configuration | Single transistor |
Configuración de pines de TIP31C
| Pin 1 | Base — Control terminal - base drive current input |
| Pin 2 | Collector — Main current terminal, connected to mounting tab |
| Pin 3 | Emitter — Main current output terminal |
Área de funcionamiento seguro (estimated from 100V/3A/40W ratings)
Aplicaciones típicas
TIP31C es adecuado para 6 aplicacións: Audio Amplifier Output Stages, Linear Voltage Regulator Pass Elements, Relay and Solenoid Drivers, DC Motor Drivers, Switching Power Circuits, LED Driver and Lighting Control.
Audio Amplifier Output Stages
The TIP31C pairs with its complementary PNP TIP32C in class-AB push-pull output stages for medium-power audio amplifiers. STMicroelectronics explicitly lists audio as a target application for this base-island-technology device. Its 100 V VCEO supports supply rails well beyond typical +/-24 V audio buses, and the 3 A continuous collector current handles speaker load peaks. The 3 MHz transition frequency comfortably exceeds the 20 kHz audio band, minimizing high-frequency phase shift. Designers should bias the output pair with a VBE multiplier for thermal tracking and mount both devices on a shared heatsink so their junction temperatures track, preventing thermal runaway in the quiescent current loop.
Recomendado
Linear Voltage Regulator Pass Elements
As a pass transistor in discrete linear regulators or as an extender for fixed three-terminal regulators such as the LM317, the TIP31C provides 3 A of output capability with a 100 V breakdown margin. In a classic pass-element configuration, the regulator IC drives the TIP31C base through a small resistor, and the transistor carries the load current outside the IC's thermal budget. Base island technology keeps saturation losses low, improving dropout performance versus older epitaxial designs. Estimated: at 2 A output with 5 V headroom the device dissipates about 10 W, requiring a heatsink below roughly 2.5 C/W effective thermal resistance. Always include short-circuit current limiting, because a bare pass transistor will fail destructively without foldback protection.
Recomendado
Relay and Solenoid Drivers
The TIP31C is a proven driver for 12 V and 24 V relays, solenoids, and contactors, switching inductive loads of up to several hundred milliamps to a few amps. Its 100 V VCEO absorbs the inductive flyback spikes that would destroy lower-voltage devices, although a flyback diode or transient clamp across the load is still mandatory best practice. A base resistor sized for a forced beta near 10 keeps the device firmly in saturation - for a 1 A load, drive with roughly 100 mA of base current. The TO-220 tab doubles as the collector connection, simplifying high-side or low-side wiring to the switching node. Switching at the few-kilohertz speeds typical of relay service is well within the 3 MHz fT capability.
Recomendado
DC Motor Drivers
For small DC motors in the 1-3 A range, the TIP31C serves as a low-side PWM switch or as one half of an H-bridge (with TIP32C as the PNP halves) in robotics, actuator, and automotive accessory circuits. The 100 V rating provides headroom for the inductive kick and regenerative braking spikes that motors generate, and the 3 MHz fT supports PWM frequencies in the 1-20 kHz range where audible whine is minimized. At PWM duty, switching losses rise with frequency, so keep drive edges sharp with adequate base overdrive. Estimated: a 2 A stalled-motor current with 1.5 V saturation dissipates roughly 3 W, so heatsinking and a stall-current limit in software or hardware are both recommended.
Recomendado
Switching Power Circuits
STMicroelectronics specifies the TIP31C for power switching applications, and it remains useful in medium-frequency switching duties such as lamp dimmers, heater controls, and low-cost buck converters operating up to tens of kilohertz. Base island technology improves switching speed and saturation characteristics versus the legacy industry-standard part it replaces. Designers must respect bipolar storage time: at high base overdrive the TIP31C stores charge that delays turn-off, so a small Baker clamp or speed-up capacitor across the base resistor improves edge fidelity. Above roughly 20-50 kHz, MOSFETs become the more efficient choice, but for simple, rugged, cost-sensitive switches at low frequency the TIP31C remains a durable and widely sourced option.
Recomendado
LED Driver and Lighting Control
The TIP31C drives high-current LED strings and incandescent lamp loads where a small-signal transistor cannot survive the current. With 3 A capability, a single TIP31C can switch multi-watt LED arrays from a microcontroller output through an appropriate base resistor. Its 100 V VCEO tolerates the voltage overhead of long LED chains on higher-voltage supplies, and the linear operating region permits simple analog dimming without PWM-induced EMI. Estimated: driving 2 A through a string dropping 5 V dissipates roughly 4 W including saturation losses, so a compact clip-on heatsink is advised for sustained operation. For dimming, PWM at 200 Hz to 1 kHz eliminates visible flicker while staying within the device's comfortable switching envelope.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para TIP31C — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | TIP31CG | TIP41C | TIP31A | 2N6122 | BDT31C |
|---|---|---|---|---|---|---|
| Package | TO-220 | TO-220 - same | TO-220 - same | TO-220 - same | TO-220 - same | TO-220 - same |
| Brand | STMicroelectronics | STMicroelectronics | STMicroelectronics | STMicroelectronics | onsemi | onsemi |
| VCEO | 100 V | 100 V | 100 V | 60 V | 100 V class | 100 V class |
| Continuous Collector Current | 3 A | 3 A | 6 A | 3 A | 4 A | 3 A |
| Polarity | NPN | NPN | NPN | NPN | NPN | NPN |
| Pinout | Base-Collector-Emitter (TO-220) | B-C-E - same | B-C-E - same | B-C-E - same | B-C-E - same | B-C-E - same |
Diferenciadores clave
- 100 V VCEO headroom (frente a TIP31A)
- Base island technology (frente a Legacy industry-standard TIP31C)
- Lower cost for sub-3A designs (frente a TIP41C)
Notas de diseño
The 40 W rating applies only at a case temperature of 25 C, which is unattainable in practice; free-air dissipation is about 2 W per distributor listings. Estimated: for a 3 W application, keep the junction under 125 C with a heatsink plus insulating pad yielding an effective Rtheta(ja) below roughly 33 C/W at 25 C ambient. Because the metal tab is the collector, always use an insulating kit (mica or silicone pad with shoulder washer) when bolting to a grounded chassis heatsink. Verify the SOA curve at your actual case temperature for linear-mode operation.
Base drive must scale with load current: hFE drops to about 10 at the full 3 A rating, so a small-signal drive of a few milliamps will leave the transistor in linear mode and destroy it thermally. Use a forced beta of 10 in switching designs (about 300 mA base current for 3 A loads) and confirm saturation on the bench. Also remember bipolar storage time - heavy base overdrive slows turn-off, so add a Baker clamp or speed-up capacitor when switching faster than a few kHz. Never operate an inductive load without a flyback diode or clamp.
The TO-220 leads support through-hole assembly only; provide generous copper area around the collector (tab) lead to conduct heat into the board when no heatsink is fitted. Keep base trace short and route it away from high dV/dt collector nodes to avoid unintended capacitive coupling that can cause parasitic turn-on in bridge configurations. For repaired or hand-built audio amplifiers, mount the TIP31C and TIP32C pair on the same heatsink with thermal compound so their VBE bias tracking remains stable across temperature cycles.
Información de cumplimiento
Compliance status not stated in the provided web data; verify against the STMicroelectronics product page (st.com/en/power-transistors/tip31c.html) before export-controlled production use.
