Infineon Technologies BSP129L6327HTSA1

Overview

BSP129L6327HTSA1 from Infineon Technologies is an N-channel depletion-mode SIPMOS® small-signal transistor in PG-SOT223 package, rated for 240 V V_DS, 6 Ω R_DS(on) max at V_GS = 0 V, and 0.35 A continuous drain current at 25 °C ambient. It features dv/dt ruggedness (6 kV/µs), AEC-Q101 qualification, and V_GS(th) banding (L-band: −1.5 to −1.3 V) for precision timing and analog switching in automotive sensor interfaces.

For engineers reviewing the BSP129L6327HTSA1 datasheet, BSP129L6327HTSA1 pinout, BSP129L6327HTSA1 application, or BSP129L6327HTSA1 equivalent, key selection criteria include depletion-mode operation for fail-safe biasing, high dv/dt immunity in inductive load switching, gate threshold voltage banding for matched channel behavior, and SOT223 thermal performance with 25 K/W R_thJS.

Technical Context

This transistor operates in depletion mode-conducting at V_GS = 0 V and requiring negative gate voltage to pinch off-making it ideal for constant-current sources and high-side load switches without external bias networks. Its 240 V V_(BR)DSS and 6 kV/µs dv/dt rating enable robust operation in automotive solenoid drivers and industrial relay interface circuits.

The L-band V_GS(th) (−1.5 to −1.3 V) ensures tight parametric grouping for matched pair applications such as differential amplifiers or current mirrors. Dynamic parameters-including 3.8–5.7 nC total gate charge and 53–80 ns reverse recovery time-support reliable switching up to several hundred kHz in low-power SMPS auxiliary rails.

Key Specifications

Pinout & Package

PG-SOT223 package with exposed drain pad (pin 4) for thermal conduction. Pin 1: Gate; Pin 2: Source; Pin 3: Drain; Pin 4: Drain (thermal tab, electrically connected to pin 3).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar depletion-mode MOSFET applications.

Compared with BSP129H6327HTSA1, the L-band version offers lower |V_GS(th)| for easier gate drive in 3.3 V logic-controlled systems; compared with BS170, BSP129L6327HTSA1 provides automotive-grade reliability, 4× higher breakdown voltage, and proven dv/dt immunity essential for production ECUs.

Availability

BSP129L6327HTSA1 is available at Aetrix Electronics and suitable for automotive sensor biasing, constant-current sinks, high-side load switching, and relay driver interfaces requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for BSP129L6327HTSA1 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

Infineon Technologies is a German semiconductor manufacturer specializing in power management, automotive electronics, and industrial control ICs, with global manufacturing and quality certification aligned to ISO/TS 16949.

The BSP129 belongs to Infineon's SIPMOS® small-signal transistor family, designed specifically for automotive and industrial applications demanding high dv/dt immunity, AEC-Q101 compliance, and parametric consistency in depletion-mode operation.

FAQ

Is BSP129L6327HTSA1 a logic-level or standard MOSFET?

No-it is a depletion-mode N-channel MOSFET, meaning it conducts at zero gate-source voltage and requires negative V_GS to turn off. Unlike enhancement-mode logic-level devices, it does not require positive gate drive and has no "logic-level" threshold; its L-band V_GS(th) is −1.5 to −1.3 V, optimized for analog biasing and fail-safe switching.

What does the "L6327" suffix indicate in BSP129L6327HTSA1?

The "L6327" denotes two attributes: "L" specifies the V_GS(th) band (−1.5 to −1.3 V), and "6327" identifies the tape-and-reel packaging format (1000 pcs/reel, dry-packed, PG-SOT223). The "HTSA1" suffix indicates Infineon's standard industrial-grade marking and environmental compliance code.

Can BSP129L6327HTSA1 replace BS170 in existing designs?

Only with circuit redesign. While both are N-channel depletion MOSFETs, BSP129L6327HTSA1 has 240 V V_DS, AEC-Q101 qualification, and dv/dt rating-unlike the 60 V, commercial-grade BS170. Direct substitution risks overvoltage failure and violates automotive qualification requirements; gate drive and thermal layout must also be re-evaluated due to SOT223 vs. TO-92 form factor.

How is thermal performance affected if pin 4 is not soldered?

If the exposed drain pad (pin 4) is not soldered to PCB copper, R_thJA rises from 70 K/W (6 cm² cooling) to 115 K/W (minimal footprint), reducing maximum allowable power dissipation by ~40 %. Junction temperature will exceed 150 °C at just 0.5 W without thermal pad connection-making soldering pin 4 mandatory for rated current operation.