onsemi 2N5172_D26Z

Overview

2N5172_D26Z from Good-Ark Semiconductor is an NPN general-purpose bipolar junction transistor in TO-92 package, rated for 30 V V_CEO, 500 mW P_C, and 500 mA I_C peak (0.5 A continuous), with h_FE ranging 70–400 at V_CE = 1 V and I_C = 100 mA. It serves as a low-voltage switching and linear amplification device in power management stages of consumer audio amplifiers and LED driver circuits.

For engineers reviewing the 2N5172_D26Z datasheet, pinout, applications, or equivalent options, key selection criteria include verified V_CEO = 30 V rating, guaranteed h_FE ≥ 70 at 100 mA, TO-92 mechanical compatibility, f_T = 300 MHz typical, and thermal resistance R_θJA = 250 °C/W under standard PCB mounting conditions.

Technical Context

The 2N5172_D26Z operates as a silicon NPN BJT with fixed-emitter configuration and base-controlled current amplification. Its DC current gain exhibits two defined test conditions: h_FE(1) = 70–400 at V_CE = 1 V, I_C = 100 mA and h_FE(2) ≥ 25 at V_CE = 6 V, I_C = 400 mA, supporting both small-signal and medium-power switching roles.

It features low saturation voltage (V_CE(sat) ≤ 0.25 V at I_C = 100 mA, I_B = 10 mA) and high transition frequency (f_T = 300 MHz typical), enabling use in RF pre-driver stages and fast-switching DC-DC feedback paths where gain-bandwidth trade-offs are critical.

Key Specifications

Pinout & Package

2N5172_D26Z is housed in a standard through-hole TO-92 package with 3 leads. The case outline conforms to JEDEC TO-92 variant dimensions: body height 14.1–14.5 mm, lead spacing 2.44–2.64 mm (e1), and flat-side orientation marking pin 1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 2N5172_D26Z, the 2N2222A offers greater voltage margin but reduced high-current gain consistency, while the BC547B delivers superior low-current h_FE but lacks the 2N5172_D26Z's validated 400 mA I_C capability and 300 MHz f_T performance at medium current levels.

Availability

2N5172_D26Z is available at Aetrix Electronics and suitable for LED driver circuits, audio preamplifiers, DC-DC feedback switches, and RF detector buffers requiring stable component supply and consistent TO-92 mechanical fit.

Supply support for 2N5172_D26Z 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

Good-Ark Semiconductor is a China-based manufacturer specializing in discrete semiconductors, including bipolar transistors, MOSFETs, and rectifiers, with ISO 9001-certified production and AEC-Q101 qualified automotive-grade lines.

The 2N5172_D26Z belongs to Good-Ark's general-purpose NPN transistor family designed for cost-sensitive industrial control, consumer audio, and power conversion applications where reliability, thermal stability, and parametric consistency across batches are essential.

FAQ

What is the maximum continuous collector current rating for the 2N5172_D26Z?

The 2N5172_D26Z has a maximum continuous collector current rating of 0.5 A at T_A = 25°C. This value decreases with rising ambient temperature per the derating curve in Figure 8 of the datasheet, where power dissipation drops linearly above 25°C at 2 mW/°C due to R_θJA = 250 °C/W. Always verify actual I_C under worst-case thermal conditions in your layout before finalizing the 2N5172_D26Z design.

Does the 2N5172_D26Z have a specified transition frequency (f_T)?

Yes, the 2N5172_D26Z has a typical transition frequency f_T of 300 MHz, measured at V_CE = 6 V and I_C = 20 mA. This parameter is confirmed in the Electrical Characteristics table on page 2 of the official Good-Ark datasheet (Doc.US2N5172xSC2.1). It indicates usable bandwidth for small-signal amplification up to approximately 100 MHz in common-emitter configurations.

What are the pin assignments for the 2N5172_D26Z in TO-92 package?

The 2N5172_D26Z uses standard TO-92 pinout: Pin 1 is Emitter, Pin 2 is Collector, and Pin 3 is Base - with the flat side of the package facing the viewer and leads pointing downward. This assignment is explicitly labeled in the "Features" section of the Good-Ark datasheet and matches JEDEC TO-92 mechanical drawings. No alternate pinouts are documented for the 2N5172_D26Z.

Is the 2N5172_D26Z suitable for linear amplifier applications?

Yes, the 2N5172_D26Z is suitable for linear amplifier applications due to its excellent h_FE linearity across I_C = 1–400 mA (Figure 2), low V_CE(sat) ≤ 0.25 V, and wide −55°C to +150°C operating range. Its h_FE span of 70–400 at V_CE = 1 V enables predictable bias network design in Class-A and AB stages, as confirmed in the "Classification of h_FE" section of the 2N5172_D26Z datasheet.

What is the thermal resistance (R_θJA) of the 2N5172_D26Z?

The 2N5172_D26Z has a specified thermal resistance R_θJA of 250 °C/W under standard test conditions (free-air, no heatsink, JEDEC-standard PCB pad layout). This value is listed in the Absolute Maximum Ratings table and used to calculate junction temperature rise: T_J = T_A + (P_D × 250). For reliable long-term operation, keep T_J ≤ 150°C by limiting power dissipation or improving board-level thermal conduction.