| 摘要 |
PURPOSE:To select driving characteristics most suitable for respective wide- range uses by controlling the number of transistors TRs to be actually driven out of plural driving TRs connected in parallel to an output terminal. CONSTITUTION:When an external load connected to an output terminal T1 is heavy or quick switching is requested, a driving capability control register R1 is so set that buffers B12 and B13 are driven together with a buffer B11, and thereby, the performance requested to a buffer circuit is satisfied. Meanwhile, when the driving capability of the external load is not relatively requested but reduction of the power consumption is requested, the driving capability control register R1 is so set that buffers B12 and B13 are not driven, and thereby, the through current in buffers B12 and B13 is eliminated, and the power consumption in the buffer circuit is reduced to a required value. Consequently, driving characteristics most suitable for respective wide-range uses are selected. |
