IMX6ULL VDD_ARM_CAP VOLTAGE IS LESS IN BRING UP

[dibing]

Hi, 

we are using iMX6ULL processor in our IoT based project. At the bring up time, getting VDD_ARM_CAP and VDD_SOC_CAP about 1.175V. But the expected voltage for 800MHz chip is 1.2 - 1.26V.

Is it an iMX6 processor or other design issue? 

[Bio_TICFSL]

Hi Dibin,

Before ldo-bypass mode switch(i.mx6):   cpufreq    VDDSOC    VDDARM   400Mhz     0.975v     1.175v   800Mhz     1.175v     1.175v If system boot from 800Mhz, considering VDDARM setting with 1.175v after ldo-bypass mode switch, and the voltage drop which bring by internal regulator 125mv, we have to set VDDARM 1.175v+125mv = 1.3v before ldo-bypass mode switch, but the 1.3v beyond our max voltage for VDDARM. }

your i.MX6 is allright.