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

STMicroelectronics 2STL1525

Name: 2STL1525
Brand: STMicroelectronics
SKU: 2STL1525
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: 2STL1525

Manufacturer:: STMicroelectronics

Category:: Single Bipolar Transistors

Package:: TO-226-3, TO-92-3 Long Body

Datasheet:: 2STL1525.pdf

Description:: TRANS NPN 25V 5A TO-92L

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:8,346

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

Product details

Overview

2STL1525 from STMicroelectronics is a low-voltage, high-performance NPN power transistor fabricated using PB-HCD (Power Bipolar High Current Density) technology. It delivers very low V_CE(sat) (220 mV @ 3 A/300 mA), high DC current gain (h_FE = 150–500), and fast switching (t_on = 60 ns, t_off = 450 ns), enabling efficient operation in LED drive and DC-DC converter output stages.

For engineers reviewing the 2STL1525 datasheet, 2STL1525 pinout, 2STL1525 application, or 2STL1525 equivalent, this device is selected for high-current, low-saturation switching in space-constrained consumer and computing power circuits where thermal efficiency and gain stability at 3–5 A are critical.

Technical Context

The 2STL1525 operates as a medium-power NPN bipolar junction transistor optimized for linear and saturated switching modes. Its PB-HCD process enables simultaneous high h_FE (≥150 at I_C = 3 A) and ultra-low V_CE(sat), reducing conduction loss in high-duty-cycle applications like voltage regulation and LED constant-current sinks.

It features a maximum collector-emitter breakdown voltage of 95 V under V_BE = −1.5 V bias and supports pulsed peak currents up to 10 A (t_P < 5 ms). Thermal resistance R_thJA is rated at 83 °C/W, indicating suitability for PCB-mounted TO-92MOD packages without forced airflow.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CE(sat)	220 mV @ I_C = 3 A, I_B = 300 mA - enables <1 W conduction loss at full load in compact DC-DC output stages
h_FE	150–500 @ I_C = 0.5–5 A - ensures stable base drive margin across wide current range without overdesign
f_T	120 MHz @ V_CE = 10 V, I_C = 50 mA - supports clean switching up to ~10 MHz PWM frequencies
t_on/t_off	60 ns / 450 ns @ resistive load - limits switching loss in 100–500 kHz converters
P_TOT	1.5 W @ T_amb = 25 °C - defines maximum continuous dissipation on standard FR-4 with minimal copper area
V_(BR)CEX	95 V @ I_C = 1 mA, V_BE = −1.5 V - provides robustness against inductive kickback in relay/LED driver flyback paths

Pinout & Package

2STL1525 is housed in the TO-92MOD package - a modified through-hole plastic case with 3.1 mm lead spacing, 5.1 mm body height, and optimized thermal pad geometry for improved PCB heat spreading versus standard TO-92.

Pin/Terminal	Circuit Role	Design Meaning
E (Emitter)	Current sink terminal	Connected to ground or low-side return path; carries full load current with minimal voltage rise
B (Base)	Control input	Requires ~300 mA drive for full saturation at 3 A; low V_BE(sat) = 1.2 V eases driver selection
C (Collector)	Current source terminal	Connects to positive rail or inductive load; withstands 95 V transient spikes during turn-off

Key Features

Feature	Design Value
Very low V_CE(sat)	220 mV at 3 A enables >95% efficiency in 5 V/3 A LED drivers without heatsinking
High h_FE consistency	Min. 150 at I_C = 3 A ensures reliable saturation with standard logic-level base drivers
Fast switching	60 ns turn-on supports high-frequency PWM dimming and synchronous rectification control
Robust breakdown rating	95 V V_(BR)CEX allows safe use in 24 V systems with inductive transients

Applications

Emergency Lighting

LED Drive

Use Scenario: Battery-backed LED arrays requiring instant-on capability and long runtime under 12 V nominal supply.

IC Role / Device Role / Timing Role: NPN power switch controlling LED string current in constant-current mode.

Use Value: Low V_CE(sat) minimizes battery drain during sustained illumination; high h_FE simplifies base drive circuitry.

Use Scenario: High-brightness indicator or backlighting in mobile equipment with tight thermal envelopes.

IC Role / Device Role / Timing Role: Linear current regulator or PWM-controlled switch for single/dual LED strings.

Use Value: 120 MHz f_T and 60 ns t_on support flicker-free 1–5 kHz PWM dimming without overshoot.

Motherboard/HDD Power

DC-DC Converter

Use Scenario: 5 V or 3.3 V auxiliary rail enable/disable and fan control on PC motherboards and HDD PCBs.

IC Role / Device Role / Timing Role: Low-side power switch managing power sequencing and fault isolation.

Use Value: 10 A I_CM peak rating handles inrush current of small motors and capacitive loads.

Use Scenario: Output stage in non-isolated buck or boost converters for portable devices.

IC Role / Device Role / Timing Role: Saturated switch in low-voltage (<25 V input) step-down regulators.

Use Value: 25 V V_(BR)CEO and 1.5 W P_TOT support continuous 3–5 A operation at ambient ≤60 °C.

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN power switching applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
BCP56-10	SMD SOT-223 package; lower I_C (1 A) but higher h_FE (250 min); no Pb-HCD process	Not suitable for 3–5 A continuous loads; better for surface-mount space-constrained designs	Select when board real estate is limited and current demand ≤1 A
2SD1761	TO-126 package; higher V_(BR)CEO (120 V); higher R_thJA (100 °C/W); V_CE(sat) = 300 mV @ 3 A	Preferred for higher-voltage industrial supplies; less thermally efficient at same current	Select when system requires >95 V breakdown margin and can accommodate larger footprint

Compared with BCP56-10 and 2SD1761, the 2STL1525 uniquely balances high current handling (5 A), ultra-low saturation voltage (220 mV), and TO-92MOD through-hole compatibility - making it optimal for cost-sensitive, medium-power, thermally constrained consumer power stages.

Availability

2STL1525 is available at Aetrix Electronics and suitable for emergency lighting, LED drive, and motherboard/HDD power management requiring stable component supply and legacy-compatible through-hole assembly.

Supply support for 2STL1525 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, Switzerland, designing and manufacturing analog, digital, and mixed-signal ICs and discrete components for automotive, industrial, and consumer markets.

The 2STL1525 belongs to ST's legacy power bipolar transistor family, engineered specifically for high-efficiency, medium-current switching in cost-sensitive computing and portable power applications.

FAQ

Is the 2STL1525 RoHS-compliant and halogen-free?

Yes. The 2STL1525 is manufactured in ECOPACK®-compliant TO-92MOD packaging, meeting RoHS Directive 2011/65/EU and halogen-free requirements per IEC 61249-2-21. Full compliance documentation is available via ST's quality portal using order code 2STL1525.

What is the maximum safe operating temperature for continuous 5 A current?

At I_C = 5 A and V_CE(sat) ≈ 500 mV (per datasheet max), power dissipation reaches 2.5 W - exceeding the 1.5 W P_TOT rating. Continuous 5 A operation requires derating to ≤60 °C ambient with ≥2 cm² copper pour, or limiting duty cycle to maintain T_J ≤ 150 °C.

Can the 2STL1525 replace a BC337 in high-current applications?

No. While both are NPN transistors, the BC337 is rated for only 0.5 A I_C and 625 mW P_TOT. Substituting 2STL1525 for BC337 requires verifying PCB layout (TO-92MOD vs TO-92 footprint), base drive capability (300 mA vs ~10 mA), and thermal management - not a drop-in replacement.

Does ST provide SPICE models for the 2STL1525?

No official SPICE model is published by ST for the 2STL1525. Designers should use generic NPN behavioral models with parameters extracted from Tables 3 and 4 (e.g., h_FE = 300, V_CE(sat) = 0.22 V, C_CBO = 20 pF) or validate switching waveforms empirically on prototype boards.

2STL1525 Specifications

Product attributes: Attribute value

Manufacturer:: STMicroelectronics

Series:: -

Package/Case:: TO-226-3, TO-92-3 Long Body

Packaging:: Bag

Product Status:: Obsolete

Transistor Type:: NPN

Current - Collector (Ic) (Max):: 5 A

Voltage - Collector Emitter Breakdown (Max):: 25 V

Vce Saturation (Max) @ Ib, Ic:: 500mV @ 40mA, 3.5A

Current - Collector Cutoff (Max):: 100nA (ICBO)

DC Current Gain (hFE) (Min) @ Ic, Vce:: 150 @ 500mA, 2V

Power - Max:: 1.5 W

Frequency - Transition:: 120MHz

Operating Temperature:: 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-92L

2STL1525 FAQ

1.How can I place an order for 2STL1525 through Aetrix?

Please submit a Request for Quotation (RFQ) for 2STL1525 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 2STL1525 reliable?

The price and inventory of 2STL1525 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 2STL1525 is usually 5 days.

3.What payment methods are accepted for 2STL1525?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 2STL1525 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for 2STL1525?

2STL1525 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your 2STL1525 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 2STL1525?

For technical support, including 2STL1525 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 2STL1525 requirements.

6.How does Aetrix verify that 2STL1525 is sourced from the original manufacturer or authorized distributors?

All 2STL1525 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 2STL1525 meets industry standards.

7.What is the process for return or replacement of 2STL1525?

All 2STL1525 units undergo pre-shipment inspection (PSI). If there is an issue with 2STL1525, 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 2STL1525 part is unused and in its original packaging.

Return procedure for 2STL1525:

1.Submit a request within 90 days.

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

Tech Hub

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…

2026-08-21 What Is an LED Driver? Types, Circuits, Dimming, and Selection

An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…