Diodes Incorporated BCX17TA

Overview

BCX17TA from Diodes Incorporated is a PNP silicon planar medium-power transistor in SOT23 package, rated for V_CEO = −45 V, I_C = −500 mA, and P_tot = 330 mW at T_amb = 25°C; used in low-voltage switching and linear amplification stages of industrial power supplies and LED driver bias circuits.

For engineers reviewing the BCX17TA datasheet, BCX17TA pinout, BCX17TA application, or BCX17TA equivalent, key selection factors include verified h_FE range (100–600 at I_C = −100 mA), V_CE(sat) ≤ −620 mV at I_C = −500 mA/I_B = −50 mA, f_T = 100 MHz, and guaranteed operation from −55°C to +150°C.

Technical Context

This PNP bipolar junction transistor operates in common-emitter configuration with DC current gain (h_FE) specified across three collector current levels: 100–600 at I_C = −100 mA, 70–400 at I_C = −300 mA, and 40–200 at I_C = −500 mA, all at V_CE = −1 V. Its f_T of 100 MHz supports audio-frequency amplification and fast-switching applications up to ~10 MHz.

Thermal performance is defined by a maximum junction temperature of +150°C and storage range down to −55°C. The device uses planar epitaxial construction with emitter-base breakdown voltage (V_EBO) ≥ −5 V and collector-base leakage (I_CBO) ≤ −200 nA at T_j = 25°C, rising to ≤ −200 µA at T_j = 150°C.

Key Specifications

Pinout & Package

SOT23 plastic surface-mount package with standard pin assignment: Emitter (pin 1), Base (pin 2), Collector (pin 3). Thermal resistance R_θJA ≈ 370°C/W typical on FR-4 board with minimal copper.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PNP medium-power transistor applications.

Compared with BC807-40 and MMBT4403, BCX17TA uniquely guarantees h_FE ≥ 40 at I_C = −500 mA and offers highest P_tot among SOT23 PNP transistors rated for that current, making it optimal for thermally constrained linear bias and high-reliability industrial switching.

Availability

BCX17TA is available at Aetrix Electronics and suitable for industrial power supply bias, LED constant-current driver, relay driver interface, and audio preamp stage applications requiring stable component supply and extended temperature operation.

Supply support for BCX17TA 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability components for industrial, automotive, and computing markets.

The BCX17TA belongs to Diodes' legacy bipolar transistor product line, designed specifically for robust, cost-effective medium-power switching and linear amplification in space-constrained SMT applications.

FAQ

What is the maximum continuous collector current for BCX17TA?

The BCX17TA is rated for a continuous collector current (I_C) of −500 mA at T_amb = 25°C with appropriate PCB copper area. Derating is required above 25°C ambient per the published thermal resistance curve (R_θJA ≈ 370°C/W), and peak pulsed current is limited to −1000 mA with duty cycle constraints.

Does BCX17TA have a guaranteed h_FE specification at full rated current?

Yes - the BCX17TA datasheet specifies h_FE ≥ 40 (minimum) at I_C = −500 mA, V_CE = −1 V, and T_amb = 25°C. This is confirmed across production lots and distinguishes it from many SOT23 PNP transistors that only guarantee h_FE at lower currents.

Can BCX17TA be used as a direct replacement for BCX17 in existing designs?

Yes - BCX17TA is the tape-and-reel packaging variant of the BCX17, sharing identical electrical specifications, pinout, and thermal characteristics. The "TA" suffix denotes taping for automated assembly; no circuit or layout changes are required when migrating from bulk BCX17 to BCX17TA.

What is the typical transition frequency (f_T) and under what conditions is it measured?

The BCX17TA has a typical f_T of 100 MHz, measured at I_C = −10 mA, V_CE = −5 V, and f = 35 MHz test frequency. This value reflects its suitability for audio-frequency amplification and fast-switching applications up to ~10 MHz, with gain-bandwidth trade-offs governed by operating point.