I'm trying to configure PLL of LPC54102 to have 150MHz at its output. Datasheet says Cortex-M4 and optional Cortex-M0+ can work up to 150MHz.
I'm suing LPCOpen code and it seems the clock is configured for 100MHz in some examples and they really work on my board. When I try to speed up to 150MHz, the MCU doesn't work anymore. I changed Chip_SystemInit():
void Chip_SystemInit(void)
{
/* Initial internal clocking @150MHz (it was originally 100MHz) */
Chip_SetupIrcClocking(150000000);
}
Chip_SetupIrcClocking() is called as usual, but it doesn't return. It seems the critical instruction is:
Chip_Clock_SetMainClockSource(SYSCON_MAINCLKSRC_PLLOUT);
Why the MCU can work at 100MHz, but not at 150MHz? Could it really run at 150MHz?