Vishay Siliconix SI5475DC-T1-E3

Overview

SI5475DC-T1-E3 from Vishay Siliconix is a P-channel enhancement-mode TrenchFET® MOSFET rated for -12 V drain-source voltage, with 0.031 Ω R_DS(on) at V_GS = -4.5 V and -5.5 A continuous drain current at 25 °C. It features 1.8 V gate threshold compatibility, halogen-free construction per IEC 61249-2-21, and is optimized for low-voltage load switching in space-constrained DC-DC converters and battery protection circuits.

For engineers reviewing the SI5475DC-T1-E3 datasheet, SI5475DC-T1-E3 pinout, SI5475DC-T1-E3 application, or SI5475DC-T1-E3 equivalent, key selection criteria include its 1206-8 ChipFET package, -1.8 V gate drive capability, junction-to-foot thermal resistance of 15–20 °C/W, and verified performance under pulsed drain currents up to ±20 A.

Technical Context

This device operates as a single P-channel power switch with a negative gate threshold voltage (-0.45 V typical) and integrated body diode (V_SD = -0.7 to -1.2 V at -1.1 A). Its trench-based silicon structure enables low on-resistance while maintaining stable transconductance (19 S typical) and fast switching dynamics (t_d(off) = 122–180 ns).

The SI5475DC-T1-E3 is designed for surface-mount operation on FR4 boards with no requirement for solder fillets at exposed copper terminations. Thermal management relies on direct heat conduction through the drain pad to PCB copper, supported by a steady-state R_thJA of 80–95 °C/W and R_thJF of 15–20 °C/W.

Key Specifications

Pinout & Package

SI5475DC-T1-E3 uses the 1206-8 ChipFET package: a leadless, bottom-terminal surface-mount design measuring 3.0 mm × 1.8 mm with exposed drain pads on the underside. The top marking "BF" identifies the part family and lot traceability code.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar P-channel MOSFET applications.

Compared with Si7157DP-T1-GE3 and DMG1012T-7, the SI5475DC-T1-E3 delivers optimal balance of 12 V rating, 0.031 Ω on-resistance, and minimal 3.0 mm × 1.8 mm footprint-making it preferred for space-limited 5–12 V load switching where thermal headroom is moderate.

Availability

SI5475DC-T1-E3 is available at Aetrix Electronics and suitable for battery protection circuits, USB power switches, DC-DC converter synchronous rectifiers, and industrial sensor node power gates requiring stable component supply across production lifecycles.

Supply support for SI5475DC-T1-E3 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

Vishay Siliconix is a global leader in discrete semiconductors, specializing in MOSFETs, diodes, optoelectronics, and passive components with emphasis on power efficiency, reliability, and miniaturization.

The SI5475DC-T1-E3 belongs to Vishay's TrenchFET® P-channel MOSFET product line, engineered specifically for high-efficiency, low-voltage load switching in space-constrained portable and industrial electronics.

FAQ

What is the maximum continuous drain current for SI5475DC-T1-E3 at 85 °C ambient temperature?

The SI5475DC-T1-E3 supports -3.5 A continuous drain current at T_A = 85 °C, as specified in the Absolute Maximum Ratings table. This derating reflects thermal limitations of the 1206-8 ChipFET package under natural convection on standard FR4. For higher current operation at elevated ambient, PCB copper area and thermal vias must be optimized to maintain junction temperature below 150 °C. The SI5475DC-T1-E3 datasheet confirms this value under steady-state conditions with no forced airflow.

Does SI5475DC-T1-E3 require a gate resistor for stable switching in a 500 kHz DC-DC converter?

The SI5475DC-T1-E3 benefits from a small gate resistor (typically 2.2–10 Ω) to damp ringing and control dV/dt, especially given its 3.6 nC Q_gd and low 19–29 nC Q_g. While not strictly required for functionality, a series gate resistor improves EMI performance and prevents shoot-through in half-bridge configurations. The SI5475DC-T1-E3's fast 15–25 ns turn-on delay and 80–120 ns fall time make controlled edge rates essential at 500 kHz switching frequencies.

Can SI5475DC-T1-E3 be used in a high-side configuration with 3.3 V logic control?

No-SI5475DC-T1-E3 is a P-channel MOSFET requiring a negative gate-to-source voltage for enhancement. With a 3.3 V logic high, the gate would sit at 3.3 V while the source is at V_IN (e.g., 5 V), resulting in V_GS = -1.7 V, which is insufficient for full turn-on (R_DS(on) rises sharply below -2.5 V). To drive SI5475DC-T1-E3 in high-side mode, a dedicated gate driver or charge pump generating ≥-4.5 V relative to source is required. Direct 3.3 V logic control only works in low-side configurations.

What is the peak pulsed drain current rating for SI5475DC-T1-E3, and under what conditions is it valid?

The SI5475DC-T1-E3 has a peak pulsed drain current rating of ±20 A, defined for pulse widths ≤300 µs and duty cycles ≤2 % at T_J = 25 °C. This rating assumes adequate PCB copper mass to absorb transient energy without exceeding the 150 °C maximum junction temperature. It is not sustainable under DC or high-duty-cycle conditions-the SI5475DC-T1-E3's continuous rating remains -5.5 A at 25 °C ambient. Pulse testing follows JEDEC JESD24-1 guidelines.

Is SI5475DC-T1-E3 compatible with lead-free reflow profiles per IPC/JEDEC J-STD-020?

Yes-SI5475DC-T1-E3 is qualified for lead-free reflow with a peak temperature of 260 °C, compliant with IPC/JEDEC J-STD-020 Class 3 moisture sensitivity level (MSL) requirements. The device is marked "T1-E3" to indicate lead-free (Pb-free) termination and conforms to RoHS Directive 2002/95/EC. No pre-bake is required for standard MSL handling, but storage per J-STD-033 guidelines is recommended for humidity-sensitive packaging.