Nexperia USA Inc. BC817-40,215

Overview

BC817-40,215 from Nexperia is a 45 V, 500 mA NPN general-purpose transistor in SOT23 (TO-236AB) package, optimized for switching and linear amplification with h_FE = 250–600 at V_CE = 1 V and I_C = 100 mA, used in low-voltage DC-DC converter bias circuits and microcontroller-driven LED drivers.

For engineers reviewing the BC817-40,215 datasheet, BC817-40,215 pinout, BC817-40,215 application, or BC817-40,215 equivalent, key selection criteria include guaranteed h_FE range, SOT23 thermal derating behavior, V_CE(sat) ≤ 700 mV at I_C = 500 mA/ I_B = 50 mA, and compatibility with standard FR4 PCB layouts using 1 cm² collector pad for 345 mW P_tot.

Technical Context

This discrete NPN bipolar junction transistor operates in active, saturation, and cutoff regions with defined absolute maximum ratings: V_CEO = 45 V, I_C = 500 mA continuous, I_CM = 1 A pulsed (t_p ≤ 1 ms), and T_j = 150 °C. Its DC current gain is binned to 250–600 at V_CE = 1 V and I_C = 100 mA under pulsed conditions (t_p ≤ 300 μs, δ ≤ 0.02).

Thermal performance depends on PCB mounting: R_th(j-a) = 362 K/W with 1 cm² collector copper pad, versus 500 K/W on standard footprint. Transition frequency f_T = 100 MHz at V_CE = 5 V, I_C = 10 mA, and 100 MHz test frequency, confirming suitability for low-MHz signal amplification and switching.

Key Specifications

Pinout & Package

SOT23 (TO-236AB) surface-mount plastic package with 3 leads, 1.9 mm × 1.1 mm body size, 0.45 mm lead pitch, and standardized reflow footprint per Figure 17.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BC847B,215 and MMBT3904LT1G, BC817-40 provides superior thermal capability (345 mW vs. ≤250 mW), verified h_FE at operational current (100 mA), and identical V_CEO - making it the preferred choice for 500 mA switching and precision biasing where thermal and gain consistency are critical.

Availability

BC817-40,215 is available at Aetrix Electronics and suitable for microcontroller GPIO expansion, low-voltage DC-DC bias circuits, and LED indicator panel switching requiring stable component supply across industrial temperature ranges and long-lifecycle production programs.

Supply support for BC817-40,215 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

Nexperia is a global semiconductor expert focused on essential efficiency technologies, delivering high-performance, reliable discrete and logic devices for automotive, industrial, and consumer markets.

The BC817 series belongs to Nexperia's general-purpose bipolar transistor product line, engineered for robustness, tight parameter binning, and manufacturability in high-volume SMT assembly - targeting cost-sensitive yet reliability-critical applications.

FAQ

What is the maximum continuous collector current for BC817-40,215 at 85 °C ambient?

At T_amb = 85 °C, the maximum continuous collector current is derated to approximately 375 mA. This is calculated using the 345 mW P_tot rating with 1 cm² collector pad and R_th(j-a) = 362 K/W, resulting in T_j = 85 °C + (345 mW × 362 K/W) ≈ 145 °C - leaving 5 °C margin below the 150 °C absolute max. Derating curves in Figure 1 confirm linear reduction from 500 mA at 25 °C to ~375 mA at 85 °C.

Does BC817-40,215 support automotive applications?

No. BC817-40,215 is explicitly marked as non-automotive qualified in the revision history (v.8, July 2022), with qualification changed from automotive to industrial/commercial grade. It lacks AEC-Q101 testing, and Nexperia states that inclusion in automotive systems is at the customer's sole risk and without warranty. Automotive alternatives include BC817-40Q series variants.

How does the 250–600 h_FE range affect base resistor selection?

The wide h_FE range requires designing for worst-case conduction: use h_FE = 250 to calculate minimum I_B needed for full saturation at target I_C. For example, to switch 500 mA, I_B ≥ 500 mA / 250 = 2 mA. Then select base resistor to deliver ≥2 mA at worst-case V_GPIO minus V_BE (1.2 V max), ensuring margin for temperature drift and process variation.

Can BC817-40,215 replace BC817-25 in an existing design?

Yes, with verification of bias stability. BC817-40 has higher minimum h_FE (250 vs. 160) and same V_CEO, I_C, and package. However, increased gain may cause unintended saturation in linear amplifier configurations or alter time constants in RC-coupled stages. Confirm operation across temperature and supply extremes, especially if the original design relied on BC817-25's lower h_FE corner.