Single package 30-V battery disconnect switch facilitates battery multiplexing in notebook computers

A 30-V bidirectionally blocking battery disconnect switch (BDS) for use in multiplexed-battery multimedia-notebook computers is described and demonstrated, comprising a multichip SO-16 packaged combination of a BiC/DMOS control IC and two back-to-back configured 32 Mcell/in/sup 2/ P-channel TrenchFETs. The control IC combines ground-referenced 3- to 5-V logic inputs with 2 kV ESD protection, level shifting to a 30 V supply rail, a 4 /spl mu/sec typical turn-on delay, multichannel 1.5 /spl mu/sec guaranteed break-before-make (BBM) operation, and 20 V voltage clamping protecting the gates of the highside TrenchFET switches. Total series BDS on-resistance is measured at 30 to 50 m/spl Omega/ over the 7 to 20 V specified input range consistent with 3 and 4-cell Li ion battery pack design, having 10 nA off-state and 2 /spl mu/A on-state supply currents, well below the currents required by charge-pumped highside N-channel solutions.