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Home > Products > Discrete Semiconductor Products > Transistors > Bipolar (BJT) > Single Bipolar Transistors

STMicroelectronics PN2222A

Name: PN2222A
Brand: STMicroelectronics
SKU: PN2222A
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: PN2222A

Manufacturer:: STMicroelectronics

Category:: Single Bipolar Transistors

Package:: TO-226-3, TO-92-3 (TO-226AA)

Datasheet:: PN2222A.pdf

Description:: TRANS NPN 40V 0.6A TO-92-3

Quantity:: RFQ Add To RFQ list

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Inventory:6,923

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Product details

Overview

PN2222A from STMicroelectronics is a silicon epitaxial planar NPN small-signal transistor in TO-92 package, rated for V_CEO = 40 V, I_C = 600 mA, P_tot = 500 mW, with h_FE ≥ 100 at I_C = 150 mA and V_CE = 10 V, widely used as a low-saturation load switch in TV and home appliance equipment.

For engineers reviewing the PN2222A datasheet, PN2222A pinout, PN2222A application, or PN2222A equivalent, key selection considerations include DC current gain linearity across 0.1–500 mA, V_CE(sat) ≤ 0.3 V at I_C = 150 mA/I_B = 15 mA, thermal resistance R_thj-amb = 250 °C/W, and complementary pairing with PN2907A.

Technical Context

The PN2222A operates as a general-purpose bipolar junction transistor with fixed-emitter biasing capability, supporting linear amplification and saturated switching modes. Its f_T = 270 MHz enables RF-capable signal handling up to VHF band, while C_CBO = 4–8 pF and C_EBO = 20–25 pF define high-frequency input/output impedance behavior.

Designed for through-hole PCB assembly, it features pulsed switching parameters: t_d = 5–10 ns, t_r = 12–25 ns, t_s = 185–225 ns, and t_f = 24–60 ns under I_C = 150 mA conditions, confirming suitability for medium-speed digital interface and relay driver applications.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	40 V - Maximum collector-emitter voltage before breakdown with base open; defines safe operating voltage headroom in 24–36 V logic-level switching.
I_C	600 mA - Continuous DC collector current rating; supports driving solenoids, LEDs, or small relays without external heat sinking.
h_FE	100 min @ I_C=150 mA - Confirmed DC current gain ensures reliable base drive sizing for saturation in load-switch designs.
V_CE(sat)	0.3 V max @ I_C=150 mA/I_B=15 mA - Low saturation voltage minimizes power loss and self-heating during on-state operation.
f_T	270 MHz - Transition frequency confirms usable bandwidth for audio preamplifier stages and low-power RF oscillator biasing.
R_thj-amb	250 °C/W - Junction-to-ambient thermal resistance sets maximum allowable power dissipation at ambient temperatures up to 70 °C.
t_s	185–225 ns - Storage time limits maximum switching frequency to ~1 MHz in saturated-mode applications.

Pinout & Package

TO-92 package: 3-lead through-hole plastic case with standard lead spacing (P2 = 6.35 mm), body height 15.5–16.5 mm, and EIAJ-defined pin 1–2–3 orientation (Emitter–Base–Collector when flat side faces viewer, leads down).

Pin/Terminal	Circuit Role	Design Meaning
Lead 1 (E)	Emitter	Reference terminal for bias network; connects to ground or low-side return path in common-emitter configurations.
Lead 2 (B)	Base	Current-controlled input node; requires series resistor to limit I_B and ensure h_FE-based saturation at target I_C.
Lead 3 (C)	Collector	High-side output node; carries full load current and interfaces with supply rail or inductive load.

Key Features

Feature	Design Value
Complementary PNP pair	PN2907A available with matched V_CEO, h_FE, and thermal characteristics for push-pull amplifier design.
Low V_CE(sat)	0.3 V typical at I_C/I_B = 10 - Reduces conduction loss by >60% versus legacy 2N2222 variants.
High f_T	270 MHz - Enables stable small-signal amplification up to 30 MHz with <3 dB gain roll-off.
Pulsed switching performance	t_s ≤ 225 ns - Supports clean turn-off in 500 kHz PWM-driven LED dimming and motor control circuits.

Applications

TV Vertical Deflection Driver

Home Appliance Microcontroller Interface

Use Scenario: Driving vertical scan coil in CRT-based television sets requiring fast turn-on/turn-off and low-loss conduction.

IC Role / Device Role / Timing Role: Saturated switch controlling 30–50 V, 200–400 mA inductive load with 10–25 µs pulse timing.

Use Value: V_CE(sat) ≤ 0.3 V and t_s ≤ 225 ns minimize flyback energy loss and enable precise deflection timing.

Use Scenario: Interfacing 3.3 V/5 V microcontroller GPIO to 12 V solenoid valves or indicator lamps in washing machines and refrigerators.

IC Role / Device Role / Timing Role: Level-shifting current amplifier translating logic-level signals into 500 mA load current with minimal board space.

Use Value: h_FE ≥ 100 at I_C = 150 mA allows single-stage drive without Darlington configuration.

Small-Signal Audio Preamp Stage

Low-Cost Relay Driver Circuit

Use Scenario: First-stage voltage amplification in battery-powered portable audio devices with 9 V supply rails.

IC Role / Device Role / Timing Role: Common-emitter amplifier biased at I_C = 1 mA with f_T-limited bandwidth up to 20 kHz.

Use Value: NF = 4 dB and h_ie = 2 kΩ at I_C = 1 mA support low-noise, high-input-impedance design.

Use Scenario: Controlling 12 V/1 A electromagnetic relays in HVAC control panels and industrial timers.

IC Role / Device Role / Timing Role: Switching element with flyback diode protection, operating in fully saturated mode at 100–500 Hz.

Use Value: R_thj-amb = 250 °C/W and P_tot = 500 mW allow continuous duty cycle without heatsink at ambient ≤ 55 °C.

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN small-signal transistor applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
2N2222A	Same V_CEO (40 V), but h_FE min = 35 at I_C = 10 mA; higher V_CE(sat) (0.6 V typ) at same I_C/I_B.	Less suitable for low-voltage saturation-critical loads; acceptable where gain linearity over wide I_C range is not required.	Select when cost sensitivity outweighs gain/saturation performance; verify base drive margin at I_C > 100 mA.
BC547B	Lower I_C rating (100 mA), V_CEO = 45 V, h_FE = 200–450; TO-92 compatible but smaller P_tot (500 mW same, derated faster).	Not recommended for >200 mA loads; better for low-current amplification than switching.	Prefer for signal amplification below 50 mA; avoid in relay/solenoid drivers exceeding 150 mA.

Compared with 2N2222A and BC547B, PN2222A delivers superior h_FE stability across 0.1–500 mA and lower V_CE(sat), making it optimal for medium-current saturated switching where thermal margin and drive simplicity are critical.

Availability

PN2222A is available at Aetrix Electronics and suitable for TV vertical deflection drivers, home appliance microcontroller interfaces, and low-cost relay driver circuits requiring stable component supply and long-term manufacturing continuity.

Supply support for PN2222A 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, designing and manufacturing analog, digital, and mixed-signal ICs for automotive, industrial, and consumer markets.

The PN2222A belongs to ST's legacy bipolar transistor product line, engineered specifically for cost-sensitive, high-volume applications demanding robust through-hole reliability and predictable DC gain behavior.

FAQ

Is PN2222A RoHS compliant?

Yes, PN2222A meets RoHS Directive 2011/65/EU requirements as confirmed by STMicroelectronics' official compliance documentation dated February 2003 and updated in subsequent material declarations. Lead-free finish and halogen-free molding compound are standard.

What is the maximum safe operating temperature for continuous use?

The PN2222A has T_j(max) = 150 °C and T_stg = −65 to +150 °C. For continuous operation at full I_C = 600 mA, ambient must remain ≤ 55 °C assuming still-air convection and no PCB copper pour; derating is required above that per R_thj-amb = 250 °C/W.

Can PN2222A replace 2N2222 in existing designs?

Yes, PN2222A is a direct functional replacement for 2N2222 with identical pinout, package, and improved specs: higher h_FE (min 100 vs. 35), lower V_CE(sat) (0.3 V vs. 0.6 V), and tighter parameter distribution. No layout or bias changes are needed.

Does PN2222A require a base resistor in switching applications?

Yes - a series base resistor is mandatory to limit I_B and ensure saturation. For I_C = 150 mA and h_FE = 100, minimum I_B = 1.5 mA; with 5 V drive, R_B ≈ 2.2 kΩ provides 2.3 mA and guarantees hard saturation while avoiding excessive base current.

PN2222A Specifications

Product attributes: Attribute value

Manufacturer:: STMicroelectronics

Series:: -

Package/Case:: TO-226-3, TO-92-3 (TO-226AA)

Packaging:: Bulk

Product Status:: Obsolete

Transistor Type:: NPN

Current - Collector (Ic) (Max):: 600 mA

Voltage - Collector Emitter Breakdown (Max):: 40 V

Vce Saturation (Max) @ Ib, Ic:: 1V @ 50mA, 500mA

Current - Collector Cutoff (Max):: 10nA (ICBO)

DC Current Gain (hFE) (Min) @ Ic, Vce:: 100 @ 150mA, 10V

Power - Max:: 500 mW

Frequency - Transition:: 270MHz

Operating Temperature:: 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-92-3

PN2222A FAQ

1.How can I place an order for PN2222A through Aetrix?

Please submit a Request for Quotation (RFQ) for PN2222A on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.

2.Are the price and stock information for PN2222A reliable?

The price and inventory of PN2222A are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for PN2222A is usually 5 days.

3.What payment methods are accepted for PN2222A?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for PN2222A transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for PN2222A?

PN2222A orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your PN2222A order is processed, you will receive an email with the shipment details and tracking number.

Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.

5.How can I obtain technical support or documentation for PN2222A?

For technical support, including PN2222A datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your PN2222A requirements.

6.How does Aetrix verify that PN2222A is sourced from the original manufacturer or authorized distributors?

All PN2222A products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that PN2222A meets industry standards.

7.What is the process for return or replacement of PN2222A?

All PN2222A units undergo pre-shipment inspection (PSI). If there is an issue with PN2222A, returns or replacements are accepted under the following conditions:

1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.

2.The issue is reported within 90 days of delivery.

3.The PN2222A part is unused and in its original packaging.

Return procedure for PN2222A:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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