Diodes Incorporated BCP68TA

Overview

BCP68TA from ON Semiconductor is an NPN silicon planar medium-power transistor designed for audio-frequency driver and output stage applications, featuring V_CEO = 20 V, I_C = 1 A continuous, P_tot = 2 W at T_amb = 25°C, V_CE(sat) = 0.5 V at I_C = 1 A / I_B = 100 mA, and h_FE up to 400 - used in low-voltage amplifier stages of consumer audio equipment.

For engineers reviewing the BCP68TA datasheet, BCP68TA pinout, BCP68TA application, or BCP68TA equivalent, key selection considerations include saturation voltage under high-current drive, thermal derating above 25°C ambient, DC current gain variation across operating conditions, and complementary pairing with BCP69TA for push-pull configurations.

Technical Context

This transistor operates as a linear or switching NPN device with fixed junction temperature limits (−55°C to +150°C), rated for continuous collector currents up to 1 A and pulsed peak currents up to 2 A. Its low V_CE(sat) enables efficient power delivery in Class AB audio output stages, while its f_T = 100 MHz supports stable operation into the upper AF range.

The device uses a SOT-223 surface-mount package with integrated heat sink pad, supporting PCB thermal management via copper pour under the emitter tab. Absolute maximum ratings are defined under pulsed test conditions (300 µs pulse width, ≤2% duty cycle) for safe transient handling without secondary breakdown.

Key Specifications

Pinout & Package

The BCP68TA is housed in a SOT-223 package with exposed emitter tab for thermal conduction. Pin 1 = Base, Pin 2 = Collector, Pin 3 = Emitter (tab), Pin 4 = Emitter (lead). The emitter tab is electrically connected to Pin 3 and serves as primary thermal path.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ZTX653 and MJD112, BCP68TA offers optimal balance of low saturation voltage, moderate voltage rating, and compact SOT-223 footprint for space-constrained 12–20 V audio and control applications - avoiding unnecessary voltage overhead or thermal mass.

Availability

BCP68TA is available at Aetrix Electronics and suitable for audio output stages, DC motor drivers, LED current regulation, and linear voltage regulator pass elements requiring stable component supply and consistent parametric performance across production lots.

Supply support for BCP68TA 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

ON Semiconductor is a global semiconductor manufacturer specializing in power management, analog, sensors, and discrete devices for automotive, industrial, and consumer markets.

The BCP68TA belongs to ON Semiconductor's general-purpose bipolar transistor product line, engineered for cost-sensitive, medium-power linear and switching applications in audio, power conversion, and interface circuits.

FAQ

What is the maximum allowable junction temperature for BCP68TA?

The BCP68TA has a specified junction temperature range of −55°C to +150°C. Operation beyond +150°C risks permanent degradation of h_FE, increased leakage, and bond wire failure. Thermal design must ensure T_j ≤ 150°C under worst-case ambient and power dissipation conditions using the device's θ_JA ≈ 62.5°C/W (with 25 cm² 2-oz copper).

Can BCP68TA be used in parallel for higher current handling?

Parallel operation is not recommended due to mismatch in V_BE(on) and h_FE between units, leading to current imbalance and thermal runaway. For >1 A continuous loads, use a single higher-rated device like MJD112 or implement active current sharing with emitter resistors and matched layout - but BCP68TA itself is not characterized for paralleling.

Is BCP68TA RoHS compliant and halogen-free?

Yes, BCP68TA is RoHS compliant per Directive 2011/65/EU and halogen-free per ON Semiconductor's PPAP documentation. The SOT-223 package uses matte tin lead finish and green molding compound meeting IEC 61249-2-21 standards, with no intentional addition of brominated flame retardants or antimony trioxide.

How does BCP68TA's h_FE vary with temperature and collector current?

h_FE increases with temperature up to ~125°C then declines; at I_C = 10 mA it ranges 63–250, at I_C = 500 mA it ranges 160–400, and at I_C = 1 A it drops to 50–160. Designers must verify gain stability across operating conditions using the h_FE vs. I_C curves in the official datasheet (Rev. 3, Feb 1996).