NXP Semiconductors BSP254A,126

Overview

BSP254A,126 from NXP Semiconductors (formerly Philips) is a P-channel enhancement-mode vertical D-MOS transistor in a TO-92 variant (SOT54) package, rated for −250 V drain-source voltage, 10–15 Ω on-state resistance at −10 V gate drive, and −0.2 A DC drain current. It serves as a line current interruptor in relay drivers, high-speed switching circuits, and line transformer drivers.

For engineers reviewing the BSP254A,126 datasheet, BSP254A,126 pinout, BSP254A,126 application, or BSP254A,126 equivalent, key selection criteria include its −250 V blocking capability, gate-threshold voltage range (0.8–2.8 V), fast switching times (5–10 ns turn-on, 20–30 ns turn-off), low gate leakage (<100 nA), and compatibility with CMOS/TTL logic interfaces.

Technical Context

This device uses a vertical D-MOS structure optimized for high-voltage P-channel switching with no secondary breakdown limitation. Its gate-source threshold voltage (0.8–2.8 V) enables direct interface with standard logic families without level-shifting.

Thermal performance is defined by R_{th j-a} = 125 K/W (on PCB with 10 mm × 10 mm drain pad), and it supports peak drain currents up to −0.6 A. The input capacitance (65–90 pF) and feedback capacitance (6–15 pF) are specified at 1 MHz and V_GS = 0, supporting predictable high-speed gate drive design.

Key Specifications

Pinout & Package

Package: TO-92 variant (SOT54), plastic single-ended leaded through-hole package with 3 leads; dimensions per IEC/JEDEC outline (D = 4.8 mm, E = 4.2 mm, L = 14.5 mm).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar P-channel high-voltage switching applications.

Compared with BSP254A,126, the BSP250,126 offers lower R_DS(on) but insufficient voltage margin for AC line use, while IRF9530PBF delivers far higher current capacity but demands mechanical and thermal redesign-neither is pin-compatible, and both require application-specific validation for high-voltage interruption roles.

Availability

BSP254A,126 is available at Aetrix Electronics and suitable for relay drivers, AC line interruptors, and high-speed transformer drivers requiring stable component supply across industrial automation, telecom infrastructure, and energy metering programs.

Supply support for BSP254A,126 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

NXP Semiconductors is a global semiconductor leader focused on secure connectivity solutions for automotive, industrial, and IoT applications.

The BSP254A,126 belongs to NXP's legacy high-voltage discrete MOSFET family, designed specifically for robust, logic-compatible high-side switching in cost-sensitive, space-constrained industrial controls.

FAQ

What is the maximum continuous drain current rating for BSP254A,126?

The BSP254A,126 has a maximum DC drain current (I_D) rating of −0.2 A at T_amb = 25 °C. This value decreases linearly with rising ambient temperature due to its 125 K/W junction-to-ambient thermal resistance. At 75 °C ambient, the usable I_D drops to approximately −0.12 A to maintain T_j ≤ 150 °C. Derating must follow the published power curve in the BSP254A,126 datasheet.

Does BSP254A,126 support direct connection to 3.3 V microcontroller GPIO pins?

Yes, BSP254A,126 supports direct connection to 3.3 V GPIO because its gate-source threshold voltage (V_GS(th)) ranges from 0.8 V to 2.8 V, ensuring full enhancement at 3.3 V drive. Gate leakage remains below 100 nA, minimizing loading on the MCU output. No external level shifter or pull-up resistor is required for reliable turn-on in typical digital control applications involving the BSP254A,126.

What is the pin configuration of BSP254A,126 and how does it differ from BSP254?

The BSP254A,126 uses a TO-92 variant (SOT54) pinout where Pin 1 = Source, Pin 2 = Gate, Pin 3 = Drain. This differs from the BSP254 (same package), which assigns Pin 1 = Gate, Pin 2 = Drain, Pin 3 = Source. The reversed pinout means BSP254A,126 and BSP254 are not interchangeable without PCB layout modification. Always verify orientation markings and schematic symbols before substitution of BSP254A,126.

Can BSP254A,126 be used in avalanche energy-rated circuits?

No, the BSP254A,126 datasheet does not specify avalanche energy (E_AS) ratings or ruggedness testing. It is characterized for linear-mode and switching operation within its Safe Operating Area (SOA), with explicit "no secondary breakdown" behavior. For circuits subject to inductive kickback or unclamped inductive switching, external clamping (e.g., TVS diode or RCD snubber) is required. The BSP254A,126 is not intended for repetitive avalanche operation.

What is the thermal resistance and recommended PCB layout for BSP254A,126?

The BSP254A,126 has a junction-to-ambient thermal resistance (R_{th j-a}) of 125 K/W when mounted on a PCB with a minimum 10 mm × 10 mm copper pad connected to Pin 3 (Drain). Leads must be ≤4 mm long. To achieve rated 1 W power dissipation, this pad must be fully exposed and optionally stitched with thermal vias to inner ground planes. Without this layout, thermal performance degrades significantly-BSP254A,126 may exceed 150 °C junction temperature even at 0.5 W.