onsemi TIP41AG

Overview

TIP41AG from onsemi is a complementary NPN silicon power transistor in TO-220 package, rated for 60 V_CEO, 6 A continuous collector current, and 65 W power dissipation at T_C = 25°C, designed for linear amplifier and hard-switching applications in industrial power supplies and motor control circuits.

For engineers reviewing the TIP41AG datasheet, pinout, applications, or equivalent options, key selection considerations include V_CEO = 60 V, I_C = 6.0 A, h_FE ≥ 30 (at I_C = 0.3 A), V_CE(sat) ≤ 1.5 V (at I_C = 6 A, I_B = 600 mA), and R_JC = 1.67 °C/W thermal resistance - all critical for thermal design and saturation loss estimation in discrete power stages.

Technical Context

The TIP41AG operates as a general-purpose NPN bipolar junction transistor with fixed gain structure optimized for Class AB audio amplifiers and relay/LED driver switching. Its DC current gain (h_FE) ranges from 30 to 75 depending on operating point, and it supports unclamped inductive switching up to 62.5 mJ under defined test conditions (I_C = 2.5 A, L = 20 mH, V_CC = 10 V).

Thermal performance is defined by R_JC = 1.67 °C/W and R_JA = 57 °C/W, enabling direct heatsink mounting without isolation washers. Safe operating area (SOA) curves in the datasheet specify second-breakdown-limited pulse operation up to 10 ms at 6 A and 60 V, with derating above 25°C case temperature.

Key Specifications

Pinout & Package

Package: TO-220-3 (Case 221A, Style 1), Pb-free, UL 94 V-0 compliant epoxy housing. Mounting tab is electrically connected to collector.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MJD127G and TIP31C, the TIP41AG offers superior thermal performance (R_JC = 1.67 °C/W vs. ~3.5 °C/W for DPAK), higher current capacity (6 A vs. 4 A), and tighter V_CE(sat) spec - making it preferred for thermally demanding linear and switching applications requiring robust conduction efficiency.

Availability

TIP41AG is available at Aetrix Electronics and suitable for industrial power supply regulation, DC motor speed control, and audio amplifier output stages requiring stable component supply and long-term manufacturability assurance.

Supply support for TIP41AG 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 is a global semiconductor manufacturer specializing in energy-efficient power, analog, sensing, and connectivity solutions for automotive, industrial, cloud, and consumer markets.

The TIP41AG belongs to onsemi's legacy plastic power transistor family, engineered for rugged, cost-effective discrete switching and amplification in non-automotive industrial equipment where reliability and thermal robustness are prioritized over ultra-high-frequency performance.

FAQ

What is the maximum continuous collector current rating for TIP41AG?

The TIP41AG has a maximum continuous collector current (I_C) rating of 6.0 A at T_C = 25°C. This rating assumes proper heatsinking; derating is required above 25°C case temperature at 0.52 W/°C. At ambient temperature (T_A = 25°C), the rating drops to 2.0 A due to higher thermal resistance to ambient (R_JA = 57 °C/W). Always verify junction temperature using actual layout and thermal interface conditions in your design.

Is TIP41AG pin-compatible with other TIP41x variants like TIP41G or TIP41BG?

Yes, the TIP41AG shares identical TO-220-3 (Style 1) pinout - Pin 1 = Base, Pins 2 & 4 = Collector, Pin 3 = Emitter - with all TIP41x variants including TIP41G and TIP41BG. However, voltage ratings differ: TIP41G is rated for 40 V_CEO, TIP41AG for 60 V_CEO, and TIP41BG for 80 V_CEO. Substituting across variants requires verification that the lower-voltage part meets system transient and safety margin requirements.

Does TIP41AG require a heatsink in typical switching applications?

Yes, the TIP41AG requires a heatsink in any application dissipating more than ~2 W continuously. With R_JC = 1.67 °C/W and P_D = 65 W at T_C = 25°C, even moderate conduction losses (e.g., 5 W at V_CE(sat) = 1.5 V, I_C = 3.3 A) will raise junction temperature significantly without thermal management. Use thermal interface material and mechanical mounting per onsemi's TO-220 guidelines to maintain T_J ≤ 150°C.

What is the DC current gain (h_FE) range for TIP41AG, and how does it vary with operating conditions?

The TIP41AG exhibits h_FE = 30 (min) to 75 (max) at I_C = 0.3 A and V_CE = 4.0 V, and h_FE = 15 (min) at I_C = 3.0 A under same V_CE. Gain decreases with increasing collector current and rising junction temperature. For reliable saturation in switching use, design base drive to ensure I_B ≥ I_C/10 across the full operating temperature range, referencing Figure 8 in the official datasheet.

Can TIP41AG be used in linear regulator applications, and what thermal considerations apply?

Yes, the TIP41AG is explicitly designed for general-purpose amplifier and switching applications, including linear regulators. In linear mode, power dissipation equals (V_IN − V_OUT) × I_LOAD, which can rapidly exceed safe limits. For example, at 24 V input, 5 V output, and 2 A load, dissipation is 38 W - requiring a heatsink capable of maintaining T_C ≤ 25°C. Always validate SOA compliance using Figure 5 and thermal response data from Figure 4.