This is diode (rectifier).
Part Number: SS34
Function: 3.0 A, 40 V, Schottky Barrier Rectifier (Diode)
Package: SMC (DO-214AB) Type
Manufacturer: Vishay, Onsemi
The SS32 ~ S310 series includes a high-efficiency, low power loss, general-propose Schottky rectifiers. The clipbonded leg structure provides high thermal performance and low electrical resistance. These rectifiers are suited for free wheeling, secondary rectification, and reverse polarity protection applications.
1. Metal to Silicon Rectifiers, Majority Carrier Conduction
2. Low-Forward Voltage Drop
3. Easy Pick and Place
4. High-Surge Current Capability
5. Ideal for automated placement
6. Guardring for overvoltage protection
Absolute Maximum Ratings
This product is general usage and suitable for many different applications.
Reference Site: https://www.onsemi.com/PowerSolutions/product.do?id=SS34
SS34 Diode Datasheet