problem of LPC1788 driver 7" tft lcd

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 18, 2016 by lpcware
Content originally posted in LPCWare by hujiafu on Fri Mar 18 02:41:13 MST 2016
my Environmental is LPC1788 CCLK@108MHz, PCLK@54MHz, EMCCLK@54MHz, SDRAM is 32bit width
when I driver a 4.3" TFT LCD(480*272) LCD_DCLK is 6MHz, the wave of LCD_DCLK is OK, also the LCD is display fine
but when I driver a 7" TFT LCD (800*480) LCD_DCLK is 36MHz(CCLK/3), the wave of LCD_DCLK range is so small.
follow is a pictrue of LCD_DCLK (36MHz), range from 1.8V - 2.8V,
Can any one help me,
Thank you!!!