| 摘要 |
PURPOSE:To reduce a noise at the time of the switching an output circuit by lowering the current drive performance of a drive circuit to control the output circuit. CONSTITUTION:The channel length and the channel width of each transistor are adjusted so that each mutual inductance gm1, gm2 of a P-channel MOS transistor M1 and an N-channel MOS transistor M2 becomes small down to one thirtieth or less of the mutual inductance gm5 of the P-channel MOS transistor M5. Namely, the current drive performances of the MOS transistors M1, M2 become small down to one thirtieth or less of that of the MOS transistor M5. Thus, di/dt to be the cause of the noise can be reduced down about to one half. Similar design can be applied to the P-channel MOS transistor M3 and the N-channel MOS transistor M4 as well. |
