onsemi PN4250_D74Z

Overview

PN4250_D74Z from Fairchild Semiconductor is a PNP general-purpose bipolar junction transistor (BJT) designed for amplification and switching in low-to-medium power circuits, with V_CEO = 40 V, I_C = 500 mA continuous, h_FE = 250–700 at I_C = 100 µA, and TO-92 radial ammo packaging (EOL code D74Z). It serves in discrete signal conditioning and load control applications up to 300 mA collector current.

For engineers reviewing the PN4250_D74Z datasheet, pinout, applications, or equivalent options, key selection considerations include its PNP polarity, TO-92 mechanical form factor, DC current gain range, saturation voltage under defined drive conditions, and thermal resistance (R_θJA = 200 °C/W).

Technical Context

The PN4250_D74Z implements a silicon planar PNP BJT structure optimized for general-purpose linear amplification and saturated switching. Its Process 68 fabrication ensures stable h_FE across temperature and consistent V_CE(sat) ≤ 0.25 V at I_C = 10 mA / I_B = 0.5 mA.

It operates within –55 °C to +150 °C junction temperature range and supports pulsed operation per factory consultation. Thermal design must account for R_θJC = 83.3 °C/W and R_θJA = 200 °C/W under standard PCB mounting conditions.

Key Specifications

Pinout & Package

PN4250_D74Z is supplied in TO-92 plastic package with radial ammo tape configuration (EOL code D74Z), flat side facing top, collector lead first exiting the package, and adhesive tape on bottom side per Figure 3.0.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPSA92 and BC557, PN4250_D74Z offers balanced performance across gain, voltage, and current capability in TO-92 packaging-making it optimal for cost-sensitive, medium-current general-purpose use cases where 40 V breakdown suffices.

Availability

PN4250_D74Z is available at Aetrix Electronics and suitable for audio pre-amplifiers, DC motor controls, LED current regulators, and level-shifting interfaces requiring stable component supply and legacy-compatible TO-92 sourcing.

Supply support for PN4250_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.

The PN4250_D74Z belongs to Fairchild's legacy general-purpose BJT product line, engineered for robustness, manufacturability, and broad applicability in industrial, consumer, and computing signal-path circuits.

FAQ

What is the pin configuration of PN4250_D74Z?

PN4250_D74Z uses TO-92 radial ammo packaging with collector (C) as the first lead exiting the package, base (B) as the center lead, and emitter (E) as the last lead. The flat side faces upward, and adhesive tape is applied to the bottom side-per Fairchild's Figure 3.0 specification for EOL code D74Z.

Does PN4250_D74Z support pulsed operation beyond its DC ratings?

Yes, PN4250_D74Z supports pulsed operation per Fairchild's note: pulse width ≤ 300 µs and duty cycle ≤ 2.0%. However, engineering validation is required for non-standard pulse conditions, and the factory should be consulted for applications involving repetitive high-peak currents or elevated ambient temperatures.

What is the typical noise figure of PN4250_D74Z and under what conditions is it measured?

PN4250_D74Z has a noise figure of 2.0 dB measured at V_CE = 5.0 V, I_C = 250 µA, R_S = 1.0 kΩ, f = 1.0 kHz, and BW = 150 Hz. This value reflects its suitability for low-noise small-signal amplification in audio and sensor interface circuits.

Can PN4250_D74Z replace PN2222A in a circuit?

No-PN4250_D74Z is a PNP transistor, whereas PN2222A is an NPN device. Direct substitution would invert logic polarity and likely cause circuit failure. For PNP replacement of PN2222A, consider complementary parts like PN2907 or MMBT2907, not PN4250_D74Z.

What thermal derating applies to PN4250_D74Z above 25°C ambient?

PN4250_D74Z derates at 5.0 mW/°C above 25°C ambient temperature. At 75°C ambient, its maximum allowable power dissipation drops to 525 mW (625 mW − [50 × 5.0]). This must be factored into heatsinking and PCB copper area planning for sustained operation.