onsemi P2N2222A

Overview

P2N2222A from ON Semiconductor is an NPN silicon general-purpose amplifier transistor in TO-92 package, rated for 40 V_CEO, 600 mA continuous collector current, and 625 mW dissipation at 25°C ambient. It delivers DC current gain (h_FE) of 75–300 at 10 mA I_C, V_CE = 10 V, and supports switching applications with 10 ns delay time and 225 ns storage time. It is widely used in low-power linear amplification and digital switching circuits in industrial control interfaces.

For engineers reviewing the P2N2222A datasheet, pinout, applications, or equivalent options, key selection considerations include its V_CEO/I_C rating trade-off, thermal resistance (R_JA = 200°C/W), saturation voltage behavior at I_C/I_B = 10, and Pb-free availability in tape-and-reel (P2N2222AZL1G) and bulk formats.

Technical Context

The P2N2222A operates as a discrete bipolar junction transistor with fixed NPN polarity and single-die construction. Its small-signal current gain (h_fe) ranges from 50 to 375 across 1–10 mA I_C, and f_T reaches 300 MHz at I_C = 20 mA, V_CE = 20 V. Junction temperature range spans −55°C to +150°C, supporting operation in non-automotive industrial environments.

Switching performance is characterized by defined delay (t_d ≤ 10 ns), rise (t_r ≤ 25 ns), storage (t_s ≤ 225 ns), and fall (t_f ≤ 60 ns) times under specified test conditions (V_CC = 30 V, I_C = 150 mA, I_B1 = I_B2 = 15 mA). Input and output capacitances (C_ibo ≤ 25 pF, C_obo ≤ 8.0 pF) are measured at 1 MHz with defined bias conditions.

Key Specifications

Pinout & Package

Package: TO-92 (Case 29-11, Style 17), through-hole, Pb-free option available (P2N2222AZL1G). Dimensions conform to ANSI Y14.5M-1982; lead pitch 2.54 mm, body height ~4.7 mm.

Key Features

Applications

Equivalent & Alternatives

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

Compared with PN2222A, P2N2222A offers identical performance with updated packaging nomenclature and Pb-free traceability; versus MMBT2222ALT1G, it trades mountability for proven through-hole reliability and legacy compatibility-critical for service replacements and industrial field upgrades.

Availability

P2N2222A is available at Aetrix Electronics and suitable for industrial control interfaces, sensor signal conditioning, and relay/LED driver circuits requiring stable component supply across extended temperature ranges and multi-year production cycles.

Supply support for P2N2222A 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 (now onsemi) is a global semiconductor supplier specializing in power management, analog, sensors, and discrete devices for automotive, industrial, and cloud infrastructure markets.

The P2N2222A belongs to ON Semiconductor's legacy general-purpose transistor family, designed for cost-sensitive, high-reliability linear amplification and digital switching in non-safety-critical industrial equipment.

FAQ

What is the maximum collector-emitter voltage rating for the P2N2222A?

The P2N2222A has a maximum collector-emitter voltage (V_CEO) rating of 40 Vdc at T_A = 25°C. This rating applies under open-base conditions and must be derated for operation at elevated ambient temperatures or with significant power dissipation. Exceeding this voltage risks avalanche breakdown and permanent device failure. The P2N2222A datasheet specifies V_CEO as a hard limit-not a recommended operating value-and actual design margin should maintain at least 20% headroom for transients.

Does the P2N2222A support Pb-free assembly processes?

Yes, the P2N2222A is available in Pb-free variants, including P2N2222AZL1G (TO-92, tape-and-reel) and P2N2222AG (TO-92, bulk). These parts comply with RoHS Directive 2011/65/EU and are qualified for standard SnPb and lead-free reflow profiles per J-STD-020. The "G" suffix explicitly denotes Pb-free construction, and the device meets ON Semiconductor's Soldering and Mounting Techniques Reference Manual requirements for thermal cycling and intermetallic formation.

What is the typical DC current gain (h_FE) of the P2N2222A at 10 mA collector current?

The P2N2222A exhibits a DC current gain (h_FE) ranging from 75 to 300 when tested at I_C = 10 mA and V_CE = 10 V, TA = 25°C. This wide spread reflects process variation and requires design tolerance-e.g., base resistor selection must accommodate minimum h_FE = 75 for guaranteed saturation. The P2N2222A datasheet also specifies h_FE = 35 at I_C = 0.1 mA and h_FE = 40 at I_C = 500 mA, confirming gain compression at extremes.

Can the P2N2222A be used in switching applications above 1 MHz?

The P2N2222A is not recommended for fundamental switching above 1 MHz due to its storage time (t_s ≤ 225 ns) and limited f_T (300 MHz). While small-signal amplification may extend into VHF, practical hard-switching efficiency degrades rapidly above 500 kHz because stored charge delays turn-off. For >1 MHz digital switching, the P2N2222A datasheet recommends using Baker clamp techniques or selecting faster alternatives like MMBT2222ALT1G-though that part requires SMT redesign.

What thermal resistance does the P2N2222A exhibit in free-air TO-92 mounting?

The P2N2222A has a thermal resistance from junction-to-ambient (R_JA) of 200°C/W when mounted in free-air TO-92 configuration per JEDEC standards. This means a 625 mW power dissipation at 25°C ambient raises junction temperature by 125°C-reaching 150°C, the absolute maximum. To sustain >300 mW continuously, forced airflow or minimal copper pad area (≥ 1 in²) is required. The P2N2222A datasheet confirms R_JA is measured without heatsink or board copper enhancement.