onsemi PN2222A_D81Z

Overview

PN2222A_D81Z from ON Semiconductor is an NPN bipolar junction transistor (BJT) designed for medium-power amplification and switching applications, with a 40 V V_CEO, 1.0 A I_C, and 625 mW power dissipation in TO-92 package. It delivers DC current gain (h_FE) of 100–300 at I_C = 150 mA and supports switching with 10 ns delay time and 225 ns storage time in typical bias conditions - widely used in relay drivers, LED drivers, and low-frequency signal amplifiers.

For engineers reviewing the PN2222A_D81Z datasheet, pinout, applications, or equivalent options, key selection considerations include its TO-92 J61Z lead form, V_CEO/V_CBO voltage ratings, h_FE variation across collector current, saturation voltage at 500 mA, and thermal resistance (R_θJA = 200 °C/W) under standard PCB mounting.

Technical Context

The PN2222A_D81Z is a silicon NPN BJT optimized for linear amplification and saturated-switching operation. Its structure supports stable DC current gain across I_C = 0.1 mA to 500 mA, with specified V_CE(sat) ≤ 1.0 V at I_C = 500 mA / I_B = 50 mA and f_T = 300 MHz at I_C = 20 mA / V_CE = 20 V.

It operates across –55 °C to +150 °C junction temperature range and features low noise figure (4.0 dB at 1 kHz), defined input/output capacitances (C_ibo = 25 pF, C_obo = 8.0 pF), and validated switching timing (t_d = 10 ns, t_s = 225 ns) under standardized test conditions per JEDEC TO-92 mechanical specification.

Key Specifications

Pinout & Package

PN2222A_D81Z is housed in a TO-92 package with J61Z lead configuration (molded, 0.200″ inline spacing), compliant with JEDEC TO-92 standards. The device has three terminals: Emitter (E), Base (B), and Collector (C), arranged in straight-lead orientation when viewed with flat side facing outward and leads downward.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BC548B and MMBT2222ALT1G, PN2222A_D81Z offers superior power handling and thermal margin in through-hole form, making it optimal for ruggedized, serviceable, or thermally demanding medium-power switching - while BC548B suits precision low-current amplification and MMBT2222ALT1G fits high-density SMT layouts with thermal mitigation.

Availability

PN2222A_D81Z is available at Aetrix Electronics and suitable for relay driver circuits, LED indicator systems, DC motor control modules, and audio pre-amplifier stages requiring stable component supply, long-term obsolescence management, and traceable sourcing.

Supply support for PN2222A_D81Z 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

ON Semiconductor is a global semiconductor manufacturer specializing in energy-efficient power management, analog, logic, and discrete devices for automotive, industrial, cloud computing, and consumer markets.

PN2222A_D81Z belongs to ON Semiconductor's legacy general-purpose bipolar transistor product line, originally developed by Fairchild Semiconductor to deliver robust, cost-effective NPN switching and amplification for broad industrial and commercial electronics.

FAQ

What is the pin configuration of PN2222A_D81Z?

PN2222A_D81Z uses the TO-92 J61Z straight-lead configuration: when viewed with the flat side facing outward and leads pointing down, the left-to-right pin order is Emitter (E), Base (B), Collector (C). This matches JEDEC TO-92 mechanical standard ZA03F and is distinct from the older BU-style TO-92 (E-C-B) variant. Pinout validation is confirmed in Fairchild's ZA03F package drawing and ON Semiconductor's updated documentation.

Does PN2222A_D81Z support switching at 100 kHz PWM?

Yes, PN2222A_D81Z supports 100 kHz PWM operation in low-duty-cycle switching applications. Its documented switching characteristics - t_d = 10 ns, t_r = 25 ns, t_s = 225 ns, t_f = 60 ns - yield a total switching time of ~320 ns, enabling clean transitions well within a 10 μs period. However, thermal limits (625 mW, R_θJA = 200 °C/W) require average power dissipation to remain below 300 mW at this frequency.

What is the maximum junction temperature for PN2222A_D81Z?

The maximum junction temperature for PN2222A_D81Z is 150 °C, as specified in its Absolute Maximum Ratings table. This limit applies under all operating conditions and is the basis for thermal derating: power dissipation must be reduced by 5.0 mW per °C above 25 °C ambient. Operation beyond 150 °C risks permanent parametric shift or catastrophic failure.

How does PN2222A_D81Z compare to the original Fairchild PN2222A?

PN2222A_D81Z is the ON Semiconductor–branded continuation of the Fairchild PN2222A, retaining identical electrical specifications, TO-92 J61Z mechanical form factor, and thermal characteristics. The "D81Z" suffix denotes the specific lead-form option (J61Z) and reflects ON Semiconductor's post-integration part numbering convention replacing underscores with dashes per internal system requirements.

Can PN2222A_D81Z replace PN2222A_BU in existing designs?

No - PN2222A_D81Z and PN2222A_BU are mechanically incompatible. PN2222A_BU uses the TO-92 BU lead form (E-C-B pinout), while PN2222A_D81Z uses J61Z (E-B-C). Swapping them without board revision causes incorrect biasing and functional failure. Electrical parameters are identical, but pinout validation confirms they are not drop-in replacements; redesign or adapter is required for migration.