Diodes Incorporated BCX6825QTA

Overview

BCX6825QTA from Diodes Incorporated is a 20V NPN medium-power bipolar junction transistor in SOT89 package, rated for 1A continuous collector current, V_CE(sat) < 500 mV at 1 A/100 mA, and qualified to AEC-Q101 for automotive use. It serves as a high-reliability power switch or MOSFET gate driver in engine control units and body electronics.

For engineers reviewing the BCX6825QTA datasheet, BCX6825QTA pinout, BCX6825QTA application, or BCX6825QTA equivalent, key selection criteria include its 20V V_CEO, 1A I_C, low saturation voltage, thermal resistance (R_θJL = 10.01 °C/W), and AEC-Q101 qualification for under-hood automotive environments.

Technical Context

This NPN BJT operates in linear or saturated switching mode with DC current gain (h_FE) ranging from 50–400 depending on bias conditions-50 min at I_C = 1 A/V_CE = 1 V, 250 min at I_C = 500 mA/V_CE = 1 V. Its f_T of 100 MHz supports fast switching in gate-drive applications.

Thermal design relies on the exposed collector pad: R_θJL = 10.01 °C/W enables efficient heat transfer to PCB copper, while R_θJA = 125 °C/W (15 mm × 15 mm FR4, 1 oz Cu) defines ambient-limited derating above 25°C.

Key Specifications

Pinout & Package

Package: SOT89 - Surface-mount plastic package with exposed collector pad for thermal and electrical connection; dimensions per AP02002 (4.50 mm × 2.50 mm × 1.05 mm); matte tin-plated leads, moisture sensitivity level 1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ZXTN25012E6TA and BCX68-16TA, BCX6825QTA uniquely combines AEC-Q101 qualification, 20 V rating, and low R_θJL for thermally constrained automotive power switching-making it the only option qualified for under-hood deployment with guaranteed supply chain traceability.

Availability

BCX6825QTA is available at Aetrix Electronics and suitable for engine control units, body control modules, and LED lighting systems requiring stable component supply across automotive production lifecycles.

Supply support for BCX6825QTA 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 automotive, industrial, and computing markets.

The BCX6825QTA belongs to Diodes' AEC-Q101-qualified bipolar transistor product line, engineered specifically for robust power switching in harsh automotive environments-including under-hood temperature cycling and vibration exposure.

FAQ

What is the maximum allowable case temperature for continuous operation?

The BCX6825QTA has an operating junction temperature range of −65°C to +150°C. With R_θJL = 10.01 °C/W and typical PCB copper area, sustained 1 A operation keeps case temperature below 125°C at +85°C ambient-verified per AEC-Q101 thermal transient testing protocols.

Is BCX6825QTA pin-compatible with BCX6925?

No-BCX6825QTA is an NPN device in SOT89 with pinout E-B-C, while BCX6925 is its complementary PNP counterpart with reversed polarity and identical SOT89 footprint but E-B-C pin assignment inverted (C-B-E). They are functionally complementary, not pin-compatible.

Can BCX6825QTA be used in linear amplifier applications?

Yes-its h_FE stability (50–400) and f_T = 100 MHz support Class-A/B audio or signal amplification up to ~10 MHz, but power dissipation must remain within 1 W derated per ambient temperature; linear use requires careful thermal design due to R_θJA = 125 °C/W on standard FR4.

Does BCX6825QTA require external base current limiting in switching mode?

Yes-base current must be limited to ≤100 mA to avoid damage; typical designs use a series resistor (e.g., 47 Ω from 5 V MCU GPIO) to ensure I_B ≈ 100 mA at V_BE(on) ≈ 1.0 V, guaranteeing saturation while respecting the 100 mA absolute max IB rating.