| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a portable terminal that can continuously perform normal display during switching resolution and has a parallel-serial conversion circuit including a PLL circuit. <P>SOLUTION: An input stop circuit 17 is provided on an input side of a PLL 16 included in the serial-parallel conversion circuit 15 of a display controller 12, and an output stop circuit 18 is provided on an output side. The input stop circuit and output stop circuit stop a PLL input clock and a PLL output clock in the start timing of a front porch of a vertical synchronization signal during the resolution switching. The input stop circuit cancels the stop of the PLL input clock when the PLL stops. The output stop circuit cancels the stop of the PLL output clock when the PLL is locked again. <P>COPYRIGHT: (C)2008,JPO&INPIT |
