STMicroelectronics BAT54SFILMY

Overview

BAT54SFILMY from STMicroelectronics is a dual-series-connected Schottky diode in SOT-23 package, rated for 40 V repetitive peak reverse voltage and 300 mA continuous forward current, with 7 pF typical junction capacitance and 5 ns reverse recovery time-designed for high-speed clamping and polarity protection in automotive power management circuits.

For engineers reviewing the BAT54SFILMY datasheet, BAT54SFILMY pinout, BAT54SFILMY application, or BAT54SFILMY equivalent, key selection criteria include low forward voltage (≤500 mV at 30 mA), AEC-Q101 qualification, negligible switching losses, and thermal robustness up to 150 °C junction temperature in compact surface-mount form.

Technical Context

The BAT54SFILMY integrates two Schottky diodes in series within a single SOT-23-3L package, enabling bidirectional blocking or cascaded voltage drop control without external interconnects. Its low 7 pF capacitance and sub-5 ns trr support >100 MHz signal path integrity in RF detector and high-frequency rectifier applications.

This configuration delivers inherent current balancing between series diodes under forward bias and maintains stable reverse leakage (<1 µA at 30 V, 25 °C) across -40 to +150 °C operating range-critical for automotive body control modules and infotainment power rails where thermal cycling and EMI resilience are mandatory.

Key Specifications

Pinout & Package

SOT-23-3L package: 3-terminal surface-mount plastic case, 2.75–3.04 mm length, 1.20–1.75 mm width, 0.89–1.40 mm height, with gull-wing leads and JEDEC-compliant footprint.

Key Features

Applications

Availability

BAT54SFILMY is available at Aetrix Electronics and suitable for automotive body electronics, industrial sensor interfaces, USB-C port protection, and high-frequency RF detector designs requiring stable component supply and AEC-Q101-compliant sourcing.

Supply support for BAT54SFILMY 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, power management ICs, sensors, and discrete components for automotive, industrial, and consumer markets.

The BAT54 series belongs to ST's automotive-qualified small-signal Schottky diode product line, engineered specifically for high-reliability, low-loss protection and rectification in space-constrained, thermally demanding vehicle subsystems.

FAQ

What is the pin configuration of BAT54SFILMY?

BAT54SFILMY uses a 3-pin SOT-23-3L package with Pin 1 as Anode 1, Pin 2 as the internal series junction (not externally accessible), and Pin 3 as Cathode 2. This monolithic series arrangement eliminates external wiring between two discrete Schottky diodes, reducing parasitic inductance and board area.

Is BAT54SFILMY suitable for reverse polarity protection?

Yes-BAT54SFILMY provides effective reverse polarity protection when placed in series with the power rail. Its 40 V V_RRM, 300 mA I_F, and low 500 mV forward drop at 30 mA enable efficient blocking of negative transients while minimizing voltage loss in 12 V and 24 V automotive systems.

How does BAT54SFILMY differ from BAT54FILMY?

BAT54FILMY is a single Schottky diode in SOT-23, whereas BAT54SFILMY contains two Schottky diodes connected in series within the same SOT-23 package. The "S" suffix denotes series configuration-providing double the forward voltage drop and enhanced transient blocking capability without increasing footprint.

Does BAT54SFILMY require heatsinking in typical applications?

No-BAT54SFILMY operates reliably without external heatsinking at ≤300 mA and ambient temperatures up to 85 °C, thanks to its 500 °C/W junction-to-ambient thermal resistance and low 500 mV forward voltage. Thermal derating becomes necessary only above 100 mA in enclosed environments exceeding 100 °C ambient.