onsemi BCV26_L99Z

Overview

BCV26_L99Z from onsemi is a PNP Darlington transistor designed for high-current-switching applications requiring DC current gain ≥10,000 at 10 mA, V_CEO = 30 V, and continuous collector current up to 1.2 A - used in relay drivers, lamp controls, and low-frequency power switching circuits.

For engineers reviewing the BCV26_L99Z datasheet, pinout, applications, or equivalent options, key selection criteria include guaranteed h_FE ≥4000 at 1 mA, V_CE(sat) ≤1.0 V at I_C = 100 mA/I_B = 0.1 mA, thermal resistance of 357°C/W, and SOT-23 package compatibility with space-constrained PCB layouts.

Technical Context

This device implements a monolithic Darlington pair structure with integrated base-emitter resistor network absent - external base drive required. It operates as a single-polarity, high-gain, medium-speed switch with f_T = 220 MHz under specified bias (I_C = 30 mA, V_CE = 5 V), enabling use in analog amplification and digital switching below ~10 MHz.

Rated for operation from −55°C to +150°C junction temperature, it supports industrial ambient environments. Its negative-polarity voltage/current convention (per onsemi note) mandates reversed supply polarity versus NPN counterparts, and its 350 mW power dissipation is derated linearly above 25°C at 2.8 mW/°C.

Key Specifications

Pinout & Package

SOT-23 (Case 318) surface-mount package with standard 3-pin configuration: compact footprint (2.9×1.3×1.0 mm), gull-wing leads, and JEDEC-compliant land pattern.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PNP Darlington transistor applications.

Compared with BCV26_L99Z, BCV27_L99Z offers identical performance in inverted topology, while MMDT3906 trades gain and current capacity for faster switching and lower cost - making BCV26_L99Z optimal for high-efficiency, low-drive, medium-power sourcing tasks.

Availability

BCV26_L99Z is available at Aetrix Electronics and suitable for relay drivers, lamp controls, industrial sensor interfaces, and power supply enable circuits requiring stable component supply, long-term manufacturability, and consistent parametric performance across production lots.

Supply support for BCV26_L99Z 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 is a global semiconductor supplier delivering energy-efficient, intelligent power and sensing solutions for automotive, industrial, cloud, medical, and IoT applications.

The BCV26_L99Z belongs to onsemi's general-purpose bipolar transistor product line, engineered for robust, high-gain switching in cost-sensitive industrial and consumer control systems.

FAQ

What is the maximum continuous collector current rating for BCV26_L99Z?

The BCV26_L99Z has an absolute maximum continuous collector current (I_C) rating of 1.2 A per the onsemi datasheet. However, the device is functionally characterized for reliable operation up to 800 mA under typical conditions - this reflects thermal and gain stability limits observed in actual use, not just electrical breakdown thresholds. Always verify PCB copper area and ambient temperature when operating near 800 mA.

Does BCV26_L99Z include an internal base-emitter resistor?

No, BCV26_L99Z does not integrate any base-emitter resistor. It is a bare Darlington pair requiring external base current limiting - unlike digital transistors (e.g., NSVD series). This gives designers full control over turn-on/off timing and base drive strength, but mandates careful selection of the series base resistor to avoid overdriving or insufficient saturation.

What is the polarity convention for voltage and current parameters in BCV26_L99Z specifications?

All voltage and current parameters for BCV26_L99Z follow PNP polarity convention: voltages are negative relative to ground (e.g., V_CEO = −30 V), and currents flow into the emitter and out of the collector. The datasheet explicitly states "all voltages (V) and currents (A) are negative polarity for PNP transistors," so design schematics must reflect reversed supply orientation versus NPN devices.

Can BCV26_L99Z be used in linear amplifier configurations?

While BCV26_L99Z exhibits f_T = 220 MHz and usable h_FE across collector currents, it is optimized for switching - not linear amplification. Its Darlington structure introduces significant V_BE(sat) (1.5 V) and nonlinear gain variation, and thermal instability arises above ~100 mW dissipation. For analog gain stages, discrete PNP transistors like MMBT3906 offer better linearity and thermal predictability.

Is BCV26_L99Z RoHS compliant and halogen-free?

Yes, BCV26_L99Z is manufactured in Pb-free and halide-free packaging per the onsemi ordering information, which specifies "SOT-23 (Pb-Free, Halide Free)" and conforms to JEDEC standards. The device meets RoHS Directive 2011/65/EU and is suitable for environmentally regulated industrial and consumer applications without exemption requests.