## FST4035: Low Voltage Drop Schottky Rectifier The **FST4035** is a high-power Schottky Barrier Rectifier typically used in power supplies and energy management systems. It is characterized by its high current capacity and low forward voltage drop, which enhances efficiency by reducing heat dissipation. ### 1. Key Technical Specifications The following table outlines the primary electrical characteristics of the FST4035: | Parameter | Value | Description | | :--- | :--- | :--- | | **$V_{RRM}$** | 35 V | Peak Repetitive Reverse Voltage | | **$I_{F(AV)}$** | 40 A | Average Forward Rectified Current | | **$V_F$** | ~0.55 V - 0.70 V | Maximum Forward Voltage Drop | | **$I_{FSM}$** | 400 - 600 A | Non-Repetitive Peak Surge Current | | **$T_j$** | -55 to +150 °C | Operating Junction Temperature | --- ### 2. Common Features * **Schottky Barrier Technology:** Utilizes a metal-to-silicon junction to achieve extremely fast switching speeds and low power loss. * **Dual Diode Configuration:** Often found in a "Common Cathode" or "Common Anode" center-tap configuration within a single package. * **Low Thermal Resistance:** Designed to transfer heat efficiently to an external heatsink. * **Guard Ring:** Most versions include a guard ring for over-voltage protection and long-term reliability. --- ### 3. Package Types The FST4035 is commonly manufactured in heavy-duty industrial packages to handle high current: 1. **TO-3P / TO-247:** Through-hole plastic packages used in PC power supplies. 2. **PowerTap / Modules:** Larger bolt-down modules used in industrial welders or heavy machinery. --- ### 4. Applications Because of its high current rating (40 Amps) and low voltage threshold, it is ideal for: * **Switching Mode Power Supplies (SMPS):** Secondary rectification for high-frequency DC output. * **Battery Chargers:** Preventing reverse current flow while maintaining high charging efficiency. * **Solar Panels:** Used as "bypass" or "blocking" diodes to prevent power loss in shaded conditions. * **Freewheeling Diodes:** Protecting circuits from inductive spikes in motor controllers. ---