onsemi TIP2955G

Overview

TIP2955G from onsemi is a complementary PNP silicon power transistor designed for general-purpose switching and linear amplifier applications, with 15 A continuous collector current, 60 V collector-emitter voltage, and 90 W power dissipation at TC = 25°C - used in high-current DC motor drivers and audio output stages.

For engineers reviewing the TIP2955G datasheet, pinout, applications, or equivalent options, key selection considerations include safe operating area (SOA) compliance, V_CE(sat) ≤ 1.1 V at 4.0 A, thermal resistance R_JC = 1.39 °C/W, and Pb-free TO-218 or TO-247 package compatibility.

Technical Context

The TIP2955G operates as a medium-power PNP bipolar junction transistor with fixed emitter-base and collector-base junction architecture. Its DC current gain (h_FE) ranges from 20 to 70 at I_C = 4.0 A, and it supports pulse operation up to 3.0 A under second breakdown limits at V_CE = 30 V and t = 1.0 s.

It features a robust safe operating area defined by thermal, bonding wire, and secondary breakdown boundaries. The device exhibits f_T = 2.5 MHz at I_C = 0.5 A and V_CE = 10 V, enabling use in audio-frequency amplification and low-speed switching circuits up to ~100 kHz.

Key Specifications

Pinout & Package

Available in SOT-93 (TO-218) and TO-247 packages; both are through-hole, three-terminal power packages with metal tab for heatsinking. Pin 1 = Base, Pin 2 = Collector, Pin 3 = Emitter, Pin 4 = Collector (dual-collector configuration for enhanced current handling).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MJ2955G and STP16PF10, the TIP2955G offers optimal balance of proven BJT linearity, predictable h_FE-based biasing, and industry-standard TO-218/TO-247 thermal performance - making it the preferred choice for analog power stages and legacy-compatible upgrades.

Availability

TIP2955G is available at Aetrix Electronics and suitable for high-current DC motor control, linear audio power amplifiers, adjustable linear voltage regulators, and relay/contactors driver circuits requiring stable component supply and long-term industrial availability.

Supply support for TIP2955G 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 connectivity solutions for automotive, industrial, and cloud power applications.

The TIP2955G belongs to onsemi's legacy silicon power transistor product line, engineered for rugged, cost-effective, high-current linear and switching applications in industrial controls, power supplies, and audio systems.

FAQ

What is the maximum continuous collector current rating for the TIP2955G?

The TIP2955G has a maximum continuous collector current (I_C) rating of 15 A at case temperature T_C = 25°C. This rating assumes proper heatsinking; current must be derated linearly above 25°C per the specified thermal derating factor of 0.72 W/°C. At T_C = 100°C, the usable I_C drops to approximately 9.5 A based on thermal limits. Always verify actual junction temperature using R_JC = 1.39 °C/W in your thermal design.

Does the TIP2955G have a dual-collector configuration, and how is it implemented?

Yes, the TIP2955G features a dual-collector configuration: Pin 2 and Pin 4 are both collector terminals, internally connected to the same semiconductor die region. This layout improves current distribution and thermal spreading across the metal tab. In PCB layout, both pins must be connected to the same high-current node - typically the heatsink plane or main power rail - to ensure balanced conduction and avoid localized heating. The SOT-93 (TO-218) and TO-247 packages both implement this 4-pin arrangement.

Can the TIP2955G be used as a direct replacement for the older TIP2955 (non-G suffix)?

Yes, the TIP2955G is a drop-in replacement for the non-Pb-free TIP2955 in most applications. The "G" suffix denotes Pb-free construction and identical electrical and thermal specifications per the onsemi datasheet. No changes to schematic, layout, or thermal design are required. However, reflow profile adjustments may be needed for Pb-free soldering processes, and legacy qualification documentation should be reviewed for aerospace or medical applications where material composition is audited.

What is the safe operating area (SOA) limitation for pulsed operation of the TIP2955G?

The TIP2955G SOA curve specifies a second breakdown limit of 3.0 A at V_CE = 30 V for nonrepetitive 1.0 s pulses. For shorter pulses, the limit increases - e.g., up to ~10 A at 10 ms and ~25 A at 100 µs - provided duty cycle remains ≤10% and average power stays within 90 W. These limits assume T_C = 25°C; SOA must be derated at elevated case temperatures. Refer to Figure 2 in the official TIP3055/D datasheet for full SOA boundary plots.

How does the TIP2955G's DC current gain (h_FE) vary with collector current and temperature?

The TIP2955G's h_FE is specified as 20–70 at I_C = 4.0 A and T_J = 25°C. It decreases at higher currents (e.g., min 5.0 at I_C = 10 A) and declines with rising junction temperature - typically dropping ~0.5%/°C above 25°C. For stable biasing, designs should accommodate this variation using emitter degeneration resistors or feedback networks. The h_FE vs. I_C curve (Figure 1) shows peak gain near 1–2 A, confirming optimal linear operation in that range.