onsemi PN3568_D74Z

Overview

PN3568_D74Z from Fairchild Semiconductor is an NPN general-purpose bipolar junction transistor (BJT) designed for medium-power amplification and switching applications up to 500mA collector current. It features V_CEO = 60 V, V_CBO = 80 V, h_FE = 40–120 at I_C = 30–150 mA, V_CE(sat) = 0.25 V, and operates across –55°C to +150°C junction temperature range - used in discrete audio preamplifier stages and relay driver circuits.

For engineers reviewing the PN3568_D74Z datasheet, pinout, applications, or equivalent options, key selection considerations include its TO-92 package compatibility, DC current gain linearity at 150 mA, saturation voltage under 15 mA base drive, thermal resistance (R_θJA = 200°C/W), and breakdown margin for 24 V industrial control interfaces.

Technical Context

The PN3568_D74Z is a silicon NPN BJT optimized for linear amplification and saturated switching in low-to-medium power analog and digital circuits. Its h_FE specification spans 40–120 across I_C = 30–150 mA with V_CE = 1.0 V, and V_CE(sat) remains ≤0.25 V under I_C/I_B = 10, confirming robust on-state performance.

Thermal design is constrained by R_θJA = 200°C/W and P_D = 625 mW at 25°C, derating 5.0 mW/°C above ambient - requiring heatsinking or airflow for sustained >300 mA operation. Cob = 20 pF and Cib = 80 pF support stable mid-frequency (<10 MHz) gain without unintended oscillation in common-emitter configurations.

Key Specifications

Pinout & Package

PN3568_D74Z is housed in a through-hole TO-92 package (3.60 × 4.58 × 14.47 mm), with standardized lead configuration: Emitter (Pin 1), Base (Pin 2), Collector (Pin 3).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN switching and amplification applications.

Compared with BC547B and MPSA13, PN3568_D74Z provides superior voltage margin (60 V), higher continuous current (1.0 A pulsed), and balanced h_FE linearity - making it the preferred choice for ruggedized 24 V relay and motor interface designs where reliability outweighs ultra-high gain.

Availability

PN3568_D74Z is available at Aetrix Electronics and suitable for industrial control panels, audio signal conditioning modules, and DC motor driver circuits requiring stable component supply and long-term manufacturability.

Supply support for PN3568_D74Z 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 manufacturer specializing in power management, analog, and discrete devices before its acquisition by ON Semiconductor in 2016.

PN3568_D74Z belongs to Fairchild's legacy general-purpose BJT product line, engineered for cost-sensitive, medium-power linear and switching applications in industrial, consumer, and automotive subsystems.

FAQ

What is the maximum continuous collector current rating for PN3568_D74Z?

The PN3568_D74Z is rated for 1.0 A pulsed collector current and 500 mA continuous collector current at T_A = 25°C. Derating applies above ambient temperature per the 5.0 mW/°C thermal coefficient. Exceeding 500 mA continuously without heatsinking risks junction overheating beyond the 150°C limit, so actual design current should be verified against layout thermal resistance and ambient conditions for PN3568_D74Z.

Is PN3568_D74Z suitable for audio amplifier applications?

Yes, PN3568_D74Z is explicitly characterized as a general-purpose amplifier transistor in its datasheet and supports linear operation with h_FE = 40–120 and V_CE(sat) = 0.25 V. Its Cob = 20 pF and Cib = 80 pF enable stable mid-band gain in common-emitter configurations up to ~10 MHz, making PN3568_D74Z appropriate for preamplifier and driver stages in low-noise audio circuits.

What is the pin configuration of PN3568_D74Z in the TO-92 package?

PN3568_D74Z uses standard TO-92 pinout: Pin 1 is Emitter, Pin 2 is Base, Pin 3 is Collector - confirmed by Fairchild's package drawing and absolute maximum ratings table. This configuration is consistent across all TO-92 variants of the PN3568 family, and PN3568_D74Z adheres strictly to this mechanical and electrical mapping.

Does PN3568_D74Z have built-in ESD protection?

No, PN3568_D74Z does not include integrated ESD protection diodes. As a standard silicon NPN BJT, it relies on external circuitry (e.g., series base resistors, TVS clamps on collector/emitter lines) for ESD robustness. The datasheet specifies no human-body-model (HBM) or charged-device-model (CDM) ratings, so PN3568_D74Z must be handled and assembled using standard ESD precautions during PCB assembly and testing.

Can PN3568_D74Z replace a 2N3904 in existing designs?

PN3568_D74Z is not a drop-in replacement for 2N3904 due to significant differences: higher V_CEO (60 V vs. 40 V), higher I_C (1.0 A vs. 200 mA), and lower h_FE minimum (40 vs. 100). While electrically compatible in many switching roles, base drive requirements and gain-dependent bias networks may need adjustment. PN3568_D74Z offers greater ruggedness but requires revalidation of operating point stability in 2N3904-based circuits.