onsemi BC817-16LT1

Overview

BC817-16LT1 from onsemi is an NPN silicon general-purpose transistor in SOT-23 package, rated for 45 V V_CEO, 500 mA I_C, and DC current gain (h_FE) of 100–250 at I_C = 100 mA. It operates across –55°C to +150°C and is commonly used in low-voltage switching and amplification circuits in consumer power supplies and signal conditioning stages.

For engineers reviewing the BC817-16LT1 datasheet, pinout, applications, or equivalent options, key selection criteria include its guaranteed h_FE range, V_CE(sat) ≤ 0.7 V at I_C/I_B = 10, thermal resistance of 556°C/W on FR-5 board, and SOT-23 footprint compatibility with automated assembly.

Technical Context

The BC817-16LT1 is a discrete bipolar junction transistor optimized for linear amplification and saturated switching. Its h_FE binning (100–250) ensures predictable current drive in base-controlled loads, while f_T ≥ 100 MHz supports moderate-frequency signal handling up to ~10 MHz in small-signal applications.

Thermal performance is defined for two mounting conditions: 225 mW dissipation on FR-5 board (R_θJA = 556°C/W) and 300 mW on alumina substrate (R_θJA = 417°C/W). The device features V_(BR)CEO = 45 V and V_EBO = 5.0 V, enabling use in 3.3 V/5 V logic interface and 24 V control circuits with margin.

Key Specifications

Pinout & Package

BC817-16LT1 uses the industry-standard SOT-23 (TO-236AB) surface-mount package per CASE 318-08, STYLE 6. Dimensions: 2.9 mm × 1.3 mm × 0.95 mm (L × W × H), with 0.95 mm lead pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BC817-16LT1, BC847B offers higher h_FE at low current but cannot handle 500 mA loads, while MMBT3904LT1G shares the same footprint and gain range but lacks the current and voltage headroom required for robust 24 V relay or power supply feedback use cases.

Availability

BC817-16LT1 is available at Aetrix Electronics and suitable for power supply feedback loops, microcontroller GPIO drivers, and relay coil interfaces requiring stable component supply and long-term manufacturability.

Supply support for BC817-16LT1 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, sensor, and connectivity solutions for automotive, industrial, cloud, and IoT applications.

The BC817 series belongs to onsemi's general-purpose bipolar transistor product line, designed for cost-sensitive, high-volume applications demanding reliability, consistent parametric binning, and broad operating temperature support.

FAQ

What is the maximum continuous collector current for BC817-16LT1?

The BC817-16LT1 has a maximum continuous collector current (I_C) rating of 500 mA at T_A = 25°C. Derating applies above 25°C - 1.8 mW/°C on FR-5 board - and actual usable current depends on PCB layout, ambient temperature, and thermal management. The BC817-16LT1 must not exceed this limit to avoid thermal runaway or permanent damage.

Is BC817-16LT1 pin-compatible with BC847 or MMBT3904?

Yes, BC817-16LT1 uses the standard SOT-23 package with pin 1 = Base, pin 2 = Emitter, pin 3 = Collector - identical pinout to BC847 and MMBT3904. However, it is not a direct functional replacement due to differences in I_C rating (500 mA vs. 100–200 mA) and h_FE test conditions. The BC817-16LT1 supports higher current loads but may require revalidation of base drive in existing designs.

What is the guaranteed h_FE range for BC817-16LT1 at 100 mA collector current?

The BC817-16LT1 guarantees h_FE between 100 and 250 when tested at I_C = 100 mA and V_CE = 1.0 V, per the official onsemi datasheet. This binning (marked "6A") distinguishes it from BC817-25LT1 (6B, h_FE = 160–400) and BC817-40LT1 (6C, h_FE = 250–600). Designers should use the minimum value (100) for worst-case bias calculations in the BC817-16LT1.

Can BC817-16LT1 be used in linear amplifier configurations?

Yes, the BC817-16LT1 supports linear operation with f_T ≥ 100 MHz and low noise characteristics typical of epitaxial planar NPN transistors. Its V_CE(sat) and h_FE stability across temperature make it suitable for Class-A preamplifiers and active filters where gain predictability matters. For optimal linearity, operate BC817-16LT1 within its SOA limits and avoid deep saturation or cutoff transitions.

What is the thermal resistance junction-to-ambient for BC817-16LT1 on a standard PCB?

The thermal resistance junction-to-ambient (R_θJA) for BC817-16LT1 is 556°C/W when mounted on a standard FR-5 board (1.0 × 0.75 × 0.062 in.) with the recommended SOT-23 footprint. This value assumes natural convection and defines the derating curve: power dissipation drops by 1.8 mW per °C rise above 25°C ambient. The BC817-16LT1 achieves 300 mW dissipation only on alumina substrates (R_θJA = 417°C/W).