onsemi TIP102

Overview

TIP102 from ON Semiconductor is an NPN Darlington power transistor in TO-220AB package, rated for 100 V_CEO(sus), 8 A continuous collector current, and 80 W power dissipation at T_C = 25°C. It features built-in base-emitter shunt resistors, low V_CE(sat) of 2.0 V (max) at I_C = 3.0 A, and typical DC current gain h_FE of 2500 at I_C = 4.0 A - designed for medium-power linear amplification and low-speed switching in industrial control and power supply circuits.

For engineers reviewing the TIP102 datasheet, pinout, applications, or equivalent options, key selection criteria include its 100 V sustaining voltage rating, Darlington topology with integrated biasing resistors, thermal resistance R_JC = 1.56 °C/W, unclamped inductive energy handling (30 mJ), and compatibility with standard TO-220 heatsink mounting.

Technical Context

The TIP102 implements a monolithic Darlington pair with two cascaded NPN transistors and on-chip base-emitter shunt resistors (~8.0 kΩ and ~120 Ω), enabling simplified drive requirements and stable turn-off behavior. Its high h_FE minimizes required base drive current while maintaining robust second-breakdown SOA up to 100 V and 8 A under pulsed conditions.

Thermal design is constrained by R_JA = 62.5 °C/W (free-air) and R_JC = 1.56 °C/W (case), requiring mechanical attachment to heatsinks for sustained operation above 2 W ambient dissipation. The device operates across –65°C to +150°C junction temperature range and supports unclamped inductive switching with E = 30 mJ at specified test conditions (I_C = 1.1 A, L = 50 mH, V_CC = 20 V).

Key Specifications

Pinout & Package

Package: TO-220AB (Case 221A, Style 1), through-hole, single-ended heatsink-mountable plastic package with 4 leads. Pin 1 (Base) and Pin 3 (Emitter) are electrically isolated from the metal tab (Collector, Pins 2 & 4).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN Darlington power transistor applications.

Compared with MJD1000G and TIP122, the TIP102 offers superior continuous current handling (8 A vs. 5–8 A), higher guaranteed h_FE, and proven through-hole reliability in high-vibration industrial enclosures - making it optimal for legacy-compatible, high-margin power switching where thermal management is feasible.

Availability

TIP102 is available at Aetrix Electronics and suitable for industrial motor control, linear power supply regulation, and AC/DC lamp dimmer designs requiring stable component supply, long-term obsolescence resilience, and consistent parametric performance across production batches.

Supply support for TIP102 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 (now onsemi) is a global semiconductor supplier specializing in power management, analog, sensor, and connectivity solutions for automotive, industrial, and cloud infrastructure markets.

The TIP102 belongs to the TIP100 series of complementary silicon Darlington transistors engineered for robust, cost-effective medium-power amplification and switching in non-safety-critical industrial equipment.

FAQ

What is the maximum continuous collector current rating for the TIP102?

The TIP102 is rated for 8.0 Adc continuous collector current at case temperature T_C = 25°C. Derating is required above this temperature at 0.64 W/°C. This rating assumes proper heatsinking per the R_JC = 1.56 °C/W specification. At ambient conditions without heatsinking, the usable current drops significantly due to R_JA = 62.5 °C/W - the TIP102 must be mounted to a heatsink for any sustained load above ~2 A.

Does the TIP102 have built-in base-emitter resistors, and how do they affect circuit design?

Yes, the TIP102 integrates monolithic base-emitter shunt resistors (~8.0 kΩ and ~120 Ω) as part of its Darlington structure. These resistors ensure predictable turn-off behavior and eliminate the need for external base pull-down components. This simplifies drive circuitry, improves noise immunity in industrial environments, and prevents latch-up in high-humidity or contaminated PCB conditions - a key differentiator versus discrete transistor pairs.

Can the TIP102 replace the TIP122 in an existing design?

The TIP102 can replace the TIP122 in most cases due to identical TO-220AB pinout, same 100 V_CEO(sus) rating, and compatible Darlington architecture. However, the TIP102 supports higher continuous current (8 A vs. 5 A) and delivers higher minimum h_FE (1000 vs. 1000, but typical 2500 vs. 1000), allowing reduced base drive. Thermal design must be verified, as the TIP102's higher power capability may increase localized heating if heatsinking is marginal.

What is the unclamped inductive energy rating of the TIP102, and how is it tested?

The TIP102 has a specified unclamped inductive energy rating of 30 mJ, measured under conditions of I_C = 1.1 A, L = 50 mH, pulse repetition frequency = 10 Hz, V_CC = 20 V, and R_BE = 100 Ω. This rating confirms safe operation when switching inductive loads like relays and solenoids without external snubbers - provided voltage transients remain within the 100 V_CEO(sus) limit and duty cycle stays below 10% for second-breakdown avoidance.

Is the TIP102 suitable for linear amplifier applications, and what biasing considerations apply?

Yes, the TIP102 is explicitly designed for general-purpose amplifier applications, with high h_FE and low V_CE(sat) supporting Class-A and Class-AB topologies. Biasing must account for its Darlington V_BE(on) ≈ 2.8 V (max) and thermal drift across –65°C to +150°C. Stable quiescent current requires emitter degeneration resistors and temperature-compensated bias networks - unlike small-signal transistors, the TIP102's gain variation with I_C (per Figure 9) demands careful operating point selection.