onsemi BC337ZL1G

Overview

BC337ZL1G from onsemi is an NPN silicon general-purpose amplifier transistor in TO-92 package, rated for 45 V_CEO, 800 mA continuous collector current, and 625 mW power dissipation at 25°C ambient. It delivers DC current gain (h_FE) of 100–630 depending on bias, with f_T = 210 MHz and V_CE(sat) ≤ 0.7 V at I_C = 500 mA / I_B = 50 mA - used in low-voltage switching and linear amplification stages of consumer power supplies and signal conditioning circuits.

For engineers reviewing the BC337ZL1G datasheet, pinout, applications, or equivalent options, key selection criteria include its V_CEO/I_C rating margin, h_FE binning (standard BC337 vs. −16/−25/−40 variants), thermal resistance (R_JA = 200°C/W), Pb-free TO-92 packaging, and safe operating area (SOA) limits under pulsed and DC conditions.

Technical Context

The BC337ZL1G operates as a medium-power, low-frequency NPN bipolar junction transistor optimized for linear amplification and saturated switching. Its design supports base-driven operation with V_BE(on) ≤ 1.2 V at I_C = 300 mA and exhibits Cob = 15 pF at V_CB = 10 V, enabling stable performance up to ~210 MHz f_T. Junction temperature range spans −55°C to +150°C, with R_JC = 83.3°C/W confirming efficient heat transfer to the case.

It belongs to the BC337 family sharing identical TO-92 mechanical form factor and pinout (Collector–Base–Emitter, Pin 1–2–3), but differs from BC337−25/−40 variants in guaranteed h_FE minimums and from BC338−25 in higher V_CEO/V_CBO ratings. The "ZL1G" suffix denotes Pb-free Ammo Box packaging (2000 units), per ON Semiconductor's standard ordering nomenclature.

Key Specifications

Pinout & Package

BC337ZL1G uses the industry-standard TO-92 (Case 29, Style 17) plastic package with 3 leads in straight-line configuration and lead pitch of 2.54 mm. Package dimensions comply with ANSI Y14.5M and are fully compatible with manual soldering and wave solder processes.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BC337-25RL1G and MPSA06, the BC337ZL1G provides the best balance of 45 V standoff, 800 mA current capacity, and cost-effective Pb-free TO-92 packaging - making it ideal for high-volume 24 V industrial controls where gain variation is acceptable and thermal management is passive.

Availability

BC337ZL1G is available at Aetrix Electronics and suitable for LED driver circuits, relay control interfaces, audio pre-amplifier stages, and power supply feedback transistors requiring stable component supply across automotive, industrial automation, and consumer electronics programs.

Supply support for BC337ZL1G 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, analog, sensing, and connectivity solutions for automotive, industrial, cloud, and consumer markets.

The BC337ZL1G belongs to onsemi's legacy general-purpose bipolar transistor product line, designed for cost-sensitive, high-reliability discrete amplification and switching in non-safety-critical embedded systems.

FAQ

What is the maximum collector-emitter voltage rating for BC337ZL1G?

The BC337ZL1G has a maximum collector-emitter voltage (V_CEO) rating of 45 V DC. This value is tested at I_C = 10 mA with base open and represents the absolute maximum before avalanche breakdown occurs. Operating continuously near this limit requires careful attention to SOA curves and thermal derating, especially above 25°C ambient temperature. The BC337ZL1G must not be used in circuits where transient spikes exceed 45 V without clamping protection.

Is BC337ZL1G pin-compatible with other BC337 variants like BC337-25 or BC337-40?

Yes, BC337ZL1G is fully pin-compatible with all BC337 family members including BC337-25 and BC337-40, as they share identical TO-92 package (Case 29, Style 17) and Collector–Base–Emitter pinout (Pin 1–2–3). Differences lie solely in guaranteed h_FE minima and packaging format (ZL1G = Ammo Box, RL1G = Tape & Reel), not electrical pin function or mechanical footprint.

Does BC337ZL1G meet RoHS requirements?

Yes, BC337ZL1G is a Pb-free device compliant with the EU RoHS Directive 2011/65/EU. The "G" suffix explicitly denotes RoHS-compliant packaging, confirmed by onsemi's official documentation and material declarations. It supports both leaded and lead-free soldering processes, with peak reflow temperature tolerance up to 260°C per J-STD-020.

What is the thermal resistance junction-to-ambient (R_JA) for BC337ZL1G?

The BC337ZL1G has a specified thermal resistance of R_JA = 200°C/W under natural convection conditions on a standard FR-4 PCB with minimal copper area. This value assumes no heatsink and defines the temperature rise from junction to ambient per watt dissipated. For reliable operation above 300 mW, PCB copper pour or airflow must be added to reduce effective R_JA.

Can BC337ZL1G replace BC338-25 in existing designs?

No - BC337ZL1G is not a direct replacement for BC338-25 due to differing V_CEO (45 V vs. 25 V) and V_CBO (50 V vs. 30 V) ratings. While both share TO-92 packaging and pinout, substituting BC337ZL1G into a BC338-25 design may cause overvoltage stress if the circuit operates near 25–30 V. Use BC337ZL1G only where 45 V headroom is verified and required.