Alpha and Omega Semiconductor Limited (NASDAQ: AOSL) has finally launched its eFuse product for sub-power rails in server applications. The new devices integrate a high-performance IC with protective features and our latest high SOA Trench MOSFET using AOS' superior co-packaging technology. When the eFuse is turned off, the new devices have low RDS(ON) back-to-back MOSFETs to separate the burden from the input bus.

The AOZ18101DI series is a 5A eFuse in a small DFN 3mm x 3mm. True Reverse Current Blocking (TRCB) is included in the AOZ18101DI-01 and AOZ18101DI-02 for defect scenarios where the voltage rail at VOUT is higher than the main bus at VIN, preventing reverse current. Furthermore, control for external blocking FET is also present for designs already in production by providing a drop-in replacement to current eFuse products requiring external FETs to implement the TRCB feature.

Additionally, the company confirmed that all-important power rails are regulated and secured by an eFuse device to safeguard the main power bus from disruption characterized by the abnormal load during fault situations, which is required for server products. The current flowing through the power switch is continuously monitored by the eFuse.

Moreover, the switch will restrict the current to the maximum allowable if the current exceeds the stated limit. If the high current demand continues, the switch will finally shut down, safeguarding downstream loads by acting as a fuse. The AOZ18101DI-03 and AOZ18101DI-04 have this TRCB feature deactivated for loads with strong inductive kickback, such as hard disc drives and server fans, to prevent the input power bus from being shut down due to a reverse current.