5PCS SS12 1N5817 SMA SMD DIODE

🔹 5PCS SS12 / 1N5817 – 1A 20V Schottky Barrier Rectifier Diode (SMA/DO-214AC)

A surface-mount Schottky diode featuring very low forward voltage drop and fast switching characteristics. The SS12 (or its through-hole equivalent 1N5817) is optimized for high-efficiency, low-voltage rectification and protection in space-constrained, low-power applications such as battery-operated devices and low-voltage DC-DC converters.

✅ Specifications:

• Part Number: SS12 (SMD) / 1N5817 (Through-Hole Equivalent)

• Type: Schottky Barrier Rectifier Diode

• Max Repetitive Reverse Voltage (VRRM): 20V

• Max Average Forward Rectified Current (IO): 1A

• Peak Forward Surge Current (IFSM): 25A (8.3ms single half-sine wave)

• Forward Voltage (VF): ~0.45V (Typical at 1A) – Key Low-Loss Feature

• Reverse Recovery Time (trr): Negligible (Schottky Characteristic)

• Package: SMA / DO-214AC (Surface Mount)

• Mounting Type: SMD (Surface Mount Device)

• Operating Junction Temperature: -65°C to +125°C

• Marking: SS12 printed on diode body

• Quantity: 5 pieces

⚙️ Key Features:

• Ultra-Low Forward Voltage: Typical 0.45V at 1A, maximizing efficiency and minimizing heat in low-voltage circuits.

• Fast Switching: Essentially no reverse recovery charge, making it perfect for high-frequency DC-DC converters (100kHz+).

• Compact SMD Design: Ideal for modern, miniaturized PCB layouts where every millimeter counts.

• High Efficiency: Superior to standard silicon diodes (1N4001-1N4007) in low-voltage applications due to significantly lower Vf.

• Robust for Low-Voltage Use: The 20V rating is well-suited for circuits up to 12V, providing a good safety margin.

📦 Typical Applications:

• Low-Voltage DC-DC Converters: Output rectification in 3.3V and 5V buck, boost, or SEPIC converters.

• Reverse Polarity Protection: In battery-powered devices (3.7V, 5V, 9V), USB-powered gadgets, and portable electronics.

• Freewheeling / Clamping Diodes: For low-power relays, solenoids, and inductive loads in microcontroller circuits.

• Solar & Battery Circuits: As a blocking diode in small solar panels or single-cell lithium battery protection circuits.

• Signal Demodulation & OR-ing Diodes: In low-voltage analog and digital circuits.

🔧 Polarity & Mounting Notes:

• Polarity Identification: On the SMA package, the cathode is marked with a white line or stripe on one end. The body marking “SS12” is typically read from the cathode end.

• PCB Footprint: Requires a standard SMA (DO-214AC) land pattern.

• Thermal Management: For continuous 1A operation, ensure the diode pad is connected to a sufficient copper area on the PCB for heat dissipation. The power dissipation is low (~0.45W), but proper layout ensures reliability.

⚠️ Important Design Considerations:

• Voltage Rating: The 20V rating is specifically for low-voltage circuits. Do not use in 24V or mains-derived circuits. For 12V applications, consider the SS14 (40V) for a larger safety margin against transients.

• Reverse Leakage: Higher than standard diodes, especially at high temperatures. This can be a factor in very high-impedance circuits or precision analog applications.

• Not for AC Line Rectification: This is a low-voltage, fast-switching diode. Not suitable for 50/60Hz AC mains rectification.

• Current Limit: Ensure your circuit’s average current does not exceed 1A. Consider derating at high ambient temperatures.

• Replacement: A direct, high-efficiency SMD upgrade for 1N5817 or 1N4001 in low-voltage switching circuits.