SMBJ45CA is a SMB unidirectional transient voltage suppressor manufactured by Littelfuse. This device is designed to protect sensitive electronics against voltage transients induced by inductive switching, switching power supplies, and other non-repetitive, excessively high voltages. It has a working voltage range of 5.0 to 178 V, a maximum peak pulse power of 400 W, and a reverse leakage current of 5 µA. It is in an SMB surface-mount package and has good thermal and electrical properties.