| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent a through-current of a bridge output circuit. <P>SOLUTION: A low-side off detecting circuit 10 compares a gate signal SG<SB>L</SB>of a low-side transistor M2 with a predetermined first level TH<SB>L</SB>to generate a low-side off detection signal S1 indicating that the low-side transistor M2 turns off. A low-side detection transistor MS<SB>L</SB>is of the same type with the low-side transistor M2, and has a source connected to a ground terminal 108 and receives the gate signal SG<SB>L</SB>of the low-side transistor M2 at a gate of the low-side detection transistor MS<SB>L</SB>. A first resistance R11 is provided between a drain of the low-side detection transistor MS<SB>L</SB>and a power supply terminal 106. A first bypass circuit 12 is provided in parallel with the first resistance R11, and becomes conductive when a control signal S<SB>IN</SB>has a level indicating that the low-side transistor M2 turns off, and becomes nonconductive when the signal has a level indicating that the low-side transistor M2 turns on. A signal of the drain of the low-side detection transistor MS<SB>L</SB>is output as the low-side off detection signal S1. <P>COPYRIGHT: (C)2011,JPO&INPIT |
