2007 Volume 127 Issue 3 Pages 261-266
We developed a battery protection IC integrating a low specific on-resistance bi-directional trench lateral power MOSFET (BTLPM). In the bi-directional switches, two MOSFETs share a drain region and there is neither drain contact nor drain metal wire. The developed bi-directional switches have a breakdown voltage of 23V and a specific on-resistance of 6.8mΩmm2 per one side MOSFET. Wafer-level Chip Size Package (W-CSP) is utilized, and the chip mounting area can be reduced to 3mm2, which is less than one-third of conventional multi-chip system. Parasitic wire resistance is also reduced to 5.3mΩ, which is about one-seventh of that of conventional package without thick copper layer.