onsemi 2N3704_D26Z

Overview

2N3704_D26Z from Fairchild Semiconductor is an NPN epitaxial silicon transistor designed for general-purpose amplification and switching in low-to-medium power circuits, with V_CEO = 30 V, I_C = 500 mA continuous, h_FE = 100–300 at I_C = 50 mA, V_CE(sat) ≤ 1.0 V at I_C = 100 mA/I_B = 5 mA, and TO-92 package. It serves as a discrete gain stage or digital switch in signal conditioning, logic interfacing, and driver circuits.

For engineers reviewing the 2N3704_D26Z datasheet, pinout, applications, or equivalent options, key selection criteria include DC current gain range, saturation voltage under defined drive conditions, thermal resistance (R_θJA = 200 °C/W), maximum junction temperature (150 °C), and TO-92 mechanical compatibility with legacy through-hole layouts.

Technical Context

The 2N3704_D26Z operates as a bipolar junction transistor with epitaxial base construction, optimized for linear amplification and saturated switching. Its h_FE variation (100–300) supports consistent biasing across production lots when used with emitter degeneration or feedback networks.

Thermal design relies on its R_θJA = 200 °C/W and R_θJC = 83.3 °C/W ratings; derating begins above 25 °C at 5.0 mW/°C. The device meets absolute maximum ratings including V_CBO = 50 V, V_EBO = 5.0 V, and T_J = –55 to +150 °C, enabling operation in industrial ambient environments.

Key Specifications

Pinout & Package

2N3704_D26Z is housed in a standard TO-92 plastic package with 3 leads. Pin identification follows JEDEC TO-92 outline: Lead 1 = Emitter, Lead 2 = Collector, Lead 3 = Base - verified per Fairchild Rev. B datasheet (July 2002).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN general-purpose amplifier and switching applications.

Compared with PN2222A and BC547B, the 2N3704_D26Z offers balanced performance for 30 V/500 mA switching and amplification, with proven thermal behavior (R_θJA = 200 °C/W) and industry-standard TO-92 fit-making it optimal for cost-sensitive, medium-power legacy-compatible designs.

Availability

2N3704_D26Z is available at Aetrix Electronics and suitable for industrial sensor interfaces, microcontroller peripheral drivers, audio pre-amplifiers, and legacy TTL level-shifting applications requiring stable component supply and long-term obsolescence resilience.

Supply support for 2N3704_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

Fairchild Semiconductor was a U.S.-based semiconductor company specializing in power management, analog, and discrete components before its acquisition by ON Semiconductor in 2016.

The 2N3704_D26Z belongs to Fairchild's legacy NPN general-purpose transistor family, engineered for reliability in amplification and switching roles across consumer, industrial, and computing equipment.

FAQ

What is the maximum continuous collector current rating for the 2N3704_D26Z?

The 2N3704_D26Z has a maximum continuous collector current (I_C) rating of 500 mA at T_A = 25 °C. This value decreases with rising ambient temperature due to thermal derating at 5.0 mW/°C above 25 °C, and must be validated against actual PCB layout and airflow conditions in the final design. Exceeding this rating risks thermal runaway or permanent degradation of the 2N3704_D26Z.

Does the 2N3704_D26Z support switching applications, and what is its typical V_CE(sat)?

Yes, the 2N3704_D26Z is explicitly characterized for switching use, with V_CE(sat) specified as 0.5–1.0 V at I_C = 100 mA and I_B = 5.0 mA. This low saturation voltage ensures minimal power loss during conduction, making the 2N3704_D26Z suitable for driving relays, LEDs, and small solenoids in discrete logic-level interface circuits.

What is the DC current gain (h_FE) range of the 2N3704_D26Z, and under what conditions is it measured?

The 2N3704_D26Z exhibits h_FE = 100–300 when measured at V_CE = 5.0 V and I_C = 50 mA, per Fairchild's Rev. B datasheet. This range reflects production lot variation and must be accounted for in bias network design-especially in linear amplifiers where gain stability affects output swing and distortion. Designers should verify operation across this full h_FE span for the 2N3704_D26Z.

Is the 2N3704_D26Z packaged in TO-92, and how are its pins arranged?

Yes, the 2N3704_D26Z uses the standard TO-92 package with three leads: Pin 1 = Emitter, Pin 2 = Collector, Pin 3 = Base - as confirmed in Fairchild's July 2002 datasheet. This pinout is identical to PN2222A and 2N2222, enabling direct physical substitution in existing through-hole layouts without modification when electrical parameters align.

What is the operating junction temperature range for the 2N3704_D26Z, and why does it matter?

The 2N3704_D26Z supports a junction temperature range of –55 °C to +150 °C. This wide range ensures functionality in harsh environments such as automotive engine compartments or industrial motor controls. Maintaining T_J ≤ 150 °C requires proper thermal design using R_θJA = 200 °C/W and derated power dissipation-critical for long-term reliability of the 2N3704_D26Z.