TIP112

The STMicroelectronics TIP112 is a high-gain, silicon NPN Darlington power transistor designed for applications requiring high current amplification and robust switching capabilities. Its Darlington configuration provides very high current gain, allowing low base current drive to control significant collector currents. The TIP112 is commonly used in power control, relay driving, motor control, and amplification applications in industrial, consumer, and automotive electronics.

## Electrical Characteristics

* Transistor type: NPN Darlington
* Collector-Emitter voltage (VCEO): 100 V maximum
* Collector-Base voltage (VCBO): 100 V maximum
* Emitter-Base voltage (VEBO): 5 V maximum
* Collector current (IC): 5 A continuous
* Peak collector current (ICM): 8 A pulsed
* DC current gain (hFE): 1000 minimum at IC = 3 A, VCE = 4 V
* Collector-Emitter saturation voltage (VCE(sat)): 2 V typical at IC = 3 A, IB = 60 mA
* Base-Emitter saturation voltage (VBE(sat)): 2.5 V typical at IC = 3 A
* Input impedance: High due to Darlington configuration

These electrical specifications make the TIP112 suitable for driving medium to high power loads with relatively low control currents.

## Switching and Performance

* Transition frequency (fT): 2.5 MHz typical
* Turn-on and turn-off times:

* Turn-on: 3 µs typical
* Turn-off: 5 µs typical
* Safe operating area (SOA) defined for both DC and pulsed operation
* Thermal stability provided by internal configuration and robust silicon design

The transistor provides reliable switching performance in both DC and moderate-frequency applications.

## Thermal Characteristics

* Maximum junction temperature (TJ): 150°C
* Storage temperature range: -65°C to +150°C
* Thermal resistance, junction-to-case (RθJC): 1.5°C/W typical
* Thermal resistance, junction-to-ambient (RθJA): 62.5°C/W typical in free air
* Power dissipation: 65 W maximum in free air

Adequate heatsinking is recommended for continuous high-current applications to prevent thermal runaway and ensure long-term reliability.

## Mechanical and Package Features

* Package: TO-220
* Lead configuration: Three leads (Base, Collector, Emitter)
* Mounting options: Through-hole with optional heatsink attachment
* Package dimensions: Standard TO-220 form factor for compatibility with existing designs
* Lead finish: Tin-plated for reliable soldering

The TO-220 package supports high current handling and allows easy thermal management via heatsinks or metal chassis mounting.

## Applications

* Power amplification and switching in industrial controls
* Relay and solenoid drivers
* Motor drivers for DC and stepper motors
* High-current LED or lamp drivers
* Audio amplifier output stages
* General-purpose high-current switching in consumer and automotive electronics

The TIP112 excels in situations where high gain and robust current handling are required, especially when low base drive is desirable.

## Key Features and Advantages

* High current gain (hFE ≥ 1000) for efficient control of high-power loads
* High voltage capability (VCEO = 100 V) suitable for medium-voltage circuits
* Robust collector current handling (IC = 5 A continuous, ICM = 8 A pulsed)
* Low base drive requirements due to Darlington configuration
* TO-220 package allows easy heatsinking and thermal management
* High input impedance and predictable switching characteristics
* Safe operating area defined for reliable DC and pulsed operation
* Versatile application in industrial, automotive, and consumer systems

The STMicroelectronics TIP112 is a reliable and efficient choice for high-current switching and amplification applications, combining high gain, thermal stability, and ease of integration into a wide range of systems.