Send an Inquiry

To receive a quote for your project, please fill in the following information, and we’ll get back to you promptly.

Submit Inventory List

Please fill in the following information, and we’ll get back to you promptly.

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

onsemi NSCT2222ALT1G

Name: NSCT2222ALT1G
Brand: onsemi
SKU: NSCT2222ALT1G
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: NSCT2222ALT1G

Manufacturer:: onsemi

Category:: Single Bipolar Transistors

Package:: TO-236-3, SC-59, SOT-23-3

Datasheet:: NSCT2222ALT1G.pdf

Description:: TRANS NPN 40V 0.6A SOT23-3

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:6,326

Please send an inquiry. Send us your inquiry, and we will respond immediately.

Product details

Overview

NSCT2222ALT1G from onsemi is an NPN silicon general-purpose transistor in SOT-23 package, rated for 40 V_CEO, 600 mA_C, and 225 mW dissipation on FR-5 board. It delivers DC current gain (h_FE) of 75–300 at 10–150 mA, with f_T = 300 MHz and V_CE(sat) ≤ 0.3 V at I_C/I_B = 10 - used in low-voltage switching and signal amplification circuits.

For engineers reviewing the NSCT2222ALT1G datasheet, pinout, applications, or equivalent options, key selection criteria include its SOT-23 footprint compatibility, guaranteed h_FE range across temperature, Pb-free compliance, and validated switching performance (t_d ≤ 10 ns, t_r ≤ 25 ns) under 30 V supply conditions.

Technical Context

This device operates as a discrete NPN bipolar junction transistor optimized for general-purpose linear amplification and digital switching. Its design supports stable DC biasing with V_BE(sat) = 0.6–1.2 V and V_CE(sat) = 0.3–1.0 V across I_C = 150–500 mA, while maintaining thermal resistance R_JA = 556 °C/W on FR-5 board.

Small-signal behavior is characterized by h_fe = 50–375 at 1–10 mA, C_ibo ≤ 25 pF, C_obo ≤ 8.0 pF, and NF ≤ 4.0 dB at 1 kHz - enabling use in audio preamps, sensor interface stages, and low-noise buffer designs where bandwidth and input impedance matter.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	40 V - maximum safe collector-emitter voltage before breakdown; sets upper rail limit for 3.3 V/5 V logic-level switching.
I_C (continuous)	600 mA - continuous collector current rating; supports driving small relays, LEDs, or logic gates without external heat sinking.
h_FE (min–max)	35–300 - guaranteed DC current gain range across operating conditions; enables predictable base drive sizing for saturation.
f_T	300 MHz - unity-gain frequency; confirms suitability for RF front-end buffers up to ~100 MHz with adequate gain margin.
V_CE(sat)	≤ 0.3 V @ I_C = 150 mA, I_B = 15 mA - low saturation voltage minimizes power loss and self-heating in switching applications.
R_JA (FR-5)	556 °C/W - thermal resistance defines junction-to-ambient rise per watt; limits usable power to ~225 mW at 25°C ambient.
C_obo	≤ 8.0 pF - output capacitance affects high-frequency response and Miller effect; critical for amplifier stability above 10 MHz.

Pinout & Package

SOT-23 (TO-236) surface-mount package, 3-pin, Pb-free, JEDEC-compliant outline (Case 318, Style 6). Dimensions: 2.90 × 1.30 × 1.00 mm (L × W × H), with 0.95 mm lead pitch.

Pin/Terminal	Circuit Role	Design Meaning
1	Base	Current-controlled input node; requires series resistor to limit I_B and ensure saturation at target I_C.
2	Emitter	Common reference terminal; tied to ground or low-side return path in most switch configurations.
3	Collector	Output current sink; connects to load (e.g., LED anode, relay coil) when used in low-side switching topology.

Key Features

Feature	Design Value
Pb-free SOT-23 package	Complies with RoHS Directive 2011/65/EU and J-STD-020 reflow profile; eliminates lead contamination risk in assembly.
Guaranteed h_FE at −55°C	Min 35 at I_C = 10 mA, V_CE = 10 V - ensures reliable turn-on in automotive cold-crank environments.
Low V_CE(sat) at high I_C	≤ 1.0 V @ I_C = 500 mA - reduces conduction loss in battery-powered load switches and power management blocks.
High f_T / low C_obo	300 MHz f_T with ≤ 8.0 pF C_obo - enables broadband amplification with minimal phase shift up to 50 MHz.
Wide T_J range	−55°C to +150°C operation - supports deployment in industrial motor controls and under-hood automotive modules.

Applications

LED Driver Circuit	Microcontroller GPIO Expander
Use Scenario: Driving multiple 20 mA indicator LEDs from 3.3 V MCU outputs via discrete transistors. IC Role / Device Role / Timing Role: Low-side switch controlled by GPIO; provides current gain and isolation between MCU and LED load. Use Value: V_CE(sat) ≤ 0.3 V ensures >90% efficiency at 20 mA, while h_FE ≥ 75 allows 270 Ω base resistor for full saturation from 3.3 V.	Use Scenario: Extending digital I/O count in space-constrained embedded systems using discrete transistor arrays. IC Role / Device Role / Timing Role: Digital buffer/inverter stage translating logic levels and sourcing/sinking higher current than MCU pins. Use Value: Switching times (t_d ≤ 10 ns, t_r ≤ 25 ns) support 10 MHz toggle rates; SOT-23 footprint saves PCB area vs. SOIC alternatives.
Audio Pre-amplifier Stage	Industrial Sensor Interface
Use Scenario: Low-noise voltage amplification of electret microphone output prior to ADC sampling. IC Role / Device Role / Timing Role: Common-emitter small-signal amplifier biased for linear operation at I_C = 1 mA. Use Value: NF ≤ 4.0 dB at 1 kHz and h_fe ≥ 50 enable clean 20–20 kHz signal gain without added distortion or thermal drift.	Use Scenario: Conditioning analog signals from RTDs or bridge sensors in PLC input modules. IC Role / Device Role / Timing Role: Current-source driver or level-shifting stage interfacing millivolt-level sensors to 5 V ADC references. Use Value: Stable h_FE over −40°C to +85°C and low C_ibo ≤ 25 pF minimize gain error and capacitive loading on precision sensor bridges.

LED Driver Circuit

Microcontroller GPIO Expander

Use Scenario: Driving multiple 20 mA indicator LEDs from 3.3 V MCU outputs via discrete transistors.

IC Role / Device Role / Timing Role: Low-side switch controlled by GPIO; provides current gain and isolation between MCU and LED load.

Use Value: V_CE(sat) ≤ 0.3 V ensures >90% efficiency at 20 mA, while h_FE ≥ 75 allows 270 Ω base resistor for full saturation from 3.3 V.

Use Scenario: Extending digital I/O count in space-constrained embedded systems using discrete transistor arrays.

IC Role / Device Role / Timing Role: Digital buffer/inverter stage translating logic levels and sourcing/sinking higher current than MCU pins.

Use Value: Switching times (t_d ≤ 10 ns, t_r ≤ 25 ns) support 10 MHz toggle rates; SOT-23 footprint saves PCB area vs. SOIC alternatives.

Audio Pre-amplifier Stage

Industrial Sensor Interface

Use Scenario: Low-noise voltage amplification of electret microphone output prior to ADC sampling.

IC Role / Device Role / Timing Role: Common-emitter small-signal amplifier biased for linear operation at I_C = 1 mA.

Use Value: NF ≤ 4.0 dB at 1 kHz and h_fe ≥ 50 enable clean 20–20 kHz signal gain without added distortion or thermal drift.

Use Scenario: Conditioning analog signals from RTDs or bridge sensors in PLC input modules.

IC Role / Device Role / Timing Role: Current-source driver or level-shifting stage interfacing millivolt-level sensors to 5 V ADC references.

Use Value: Stable h_FE over −40°C to +85°C and low C_ibo ≤ 25 pF minimize gain error and capacitive loading on precision sensor bridges.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
MMBT2222ALT1G	Same die, identical electrical specs; differs only in tape-and-reel packaging (3,000 vs. 10,000 pcs/reel).	No functional difference; suitable for same circuit roles including switching and amplification.	Select based on volume procurement needs and line-side reel change frequency.
PN2222A	Through-hole TO-92 package; V_CEO = 40 V, I_C = 800 mA, but h_FE min = 100 only at I_C = 10 mA - no guaranteed gain at low currents.	Requires PCB through-hole layout; not drop-in compatible due to different footprint and thermal profile.	Choose for prototyping or legacy through-hole designs; avoid for automated SMT production.

Compared with MMBT2222ALT1G and PN2222A, the NSCT2222ALT1G offers identical performance in a standardized SOT-23 package optimized for high-volume pick-and-place assembly, with verified h_FE consistency down to −55°C and tighter C_obo control for RF-sensitive layouts.

Availability

NSCT2222ALT1G is available at Aetrix Electronics and suitable for LED driver circuits, microcontroller I/O expansion, audio pre-amplifiers, and industrial sensor interfaces requiring stable component supply and RoHS-compliant manufacturing.

Supply support for NSCT2222ALT1G 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

onsemi (formerly ON Semiconductor) is a global semiconductor supplier specializing in energy-efficient power and signal management solutions for automotive, industrial, cloud, and consumer markets.

The NSCT2222ALT1G belongs to onsemi's general-purpose bipolar transistor product line, designed for cost-sensitive, high-reliability discrete switching and amplification in space-constrained applications.

FAQ

What is the maximum continuous collector current rating for NSCT2222ALT1G?

The NSCT2222ALT1G has a maximum continuous collector current (I_C) rating of 600 mA at T_A = 25°C on FR-5 board. Derating applies above 25°C at 1.8 mW/°C, limiting usable current in elevated ambient temperatures. This rating supports driving small loads like LEDs, relays, or logic inputs without external heatsinking.

Does NSCT2222ALT1G meet RoHS requirements?

Yes, the NSCT2222ALT1G is a Pb-free device compliant with the EU RoHS Directive 2011/65/EU. The "G" suffix explicitly denotes lead-free termination, and the SOT-23 package meets J-STD-020 reflow standards. No lead content is present in die attach, bond wires, or finish plating.

What is the guaranteed DC current gain (h_FE) range for NSCT2222ALT1G at room temperature?

The NSCT2222ALT1G guarantees h_FE = 35–300 at T_A = 25°C across test conditions: min 35 at I_C = 0.1 mA, max 300 at I_C = 150 mA. This wide span enables flexible biasing - e.g., 75–200 at I_C = 10 mA supports robust switching with margin against process variation.

Can NSCT2222ALT1G be used in high-frequency amplifier designs?

Yes, the NSCT2222ALT1G achieves f_T = 300 MHz and exhibits C_obo ≤ 8.0 pF, making it suitable for amplifiers up to ~100 MHz with proper layout and biasing. Its h_fe = 50–375 at 1–10 kHz and NF ≤ 4.0 dB confirm viability in RF preamps and broadband buffer stages where gain-bandwidth trade-offs matter.

What are the thermal limitations of NSCT2222ALT1G on standard FR-5 PCB?

On FR-5 board, the NSCT2222ALT1G has R_JA = 556 °C/W and P_D = 225 mW at T_A = 25°C, derating at 1.8 mW/°C. At 60°C ambient, max dissipation drops to ~162 mW - corresponding to ~270 mA at V_CE(sat) = 0.3 V. Thermal relief pads and copper pours significantly improve this limit.

NSCT2222ALT1G Specifications

Product attributes: Attribute value

Manufacturer:: onsemi

Series:: -

Package/Case:: TO-236-3, SC-59, SOT-23-3

Packaging:: Tape & Reel (TR)

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:: 225 mW

Frequency - Transition:: 300MHz

Operating Temperature:: -55°C ~ 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: SOT-23-3 (TO-236)

NSCT2222ALT1G FAQ

1.How can I place an order for NSCT2222ALT1G through Aetrix?

Please submit a Request for Quotation (RFQ) for NSCT2222ALT1G 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 NSCT2222ALT1G reliable?

The price and inventory of NSCT2222ALT1G are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for NSCT2222ALT1G is usually 5 days.

3.What payment methods are accepted for NSCT2222ALT1G?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for NSCT2222ALT1G transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for NSCT2222ALT1G?

NSCT2222ALT1G orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your NSCT2222ALT1G 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 NSCT2222ALT1G?

For technical support, including NSCT2222ALT1G datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your NSCT2222ALT1G requirements.

6.How does Aetrix verify that NSCT2222ALT1G is sourced from the original manufacturer or authorized distributors?

All NSCT2222ALT1G 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 NSCT2222ALT1G meets industry standards.

7.What is the process for return or replacement of NSCT2222ALT1G?

All NSCT2222ALT1G units undergo pre-shipment inspection (PSI). If there is an issue with NSCT2222ALT1G, 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 NSCT2222ALT1G part is unused and in its original packaging.

Return procedure for NSCT2222ALT1G:

1.Submit a request within 90 days.

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

Tech Hub

2026-09-09 Counterfeit Electronic Components: How to Detect, Authenticate, and Test Suspect Parts

Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …

2026-09-08 Obsolete Electronic Components: How to Source and Evaluate Replacements

A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.

2026-09-07 TTL vs CMOS Logic Levels: 74HC and 74HCT Compatibility Explained

TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.

2026-09-04 Logic Level Shifter: How to Connect 3.3V and 5V Logic Safely

A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.

2026-09-03 74HC595 vs TPIC6B595: Output Drive, Pinout, Current, and Load Selection

The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…

2026-09-02 74HC595 Pinout, Timing, Output Current, and Applications

The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…

2026-09-01 Latch vs Flip-Flop: Timing, Differences and Design Choices

A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…

2026-08-30 D Latch Circuit: Truth Table, Timing, ICs and Applications

A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …

2026-08-28 SR Latch Explained: NOR and NAND Circuits, Truth Tables, and Applications

An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…

2026-08-27 Latch Circuit: SR and D Latches, Truth Tables, Timing, and Applications

Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…