Hi,
I'm working on a custom board with an iMX6 Solo processor.
VDDARM_IN, and VDDSOC_IN are powered at 1.2V by a DCDC with less than 5% Vpp ripple.
My doubt is about the difference between bypassing LDOs or setting them with an output voltage greater than output.
As Igor said:
> but since in your case output voltage is set greater than input,
> LDO transistor is fully "closed"
in LDO turning from 0x1F to 0x1E cause i.MX6DL hang
I understand that the "power" part of LDOs work in exactly same way and the only difference is that when bypassing the control/analog part of LDO is disabled. Am I wrong?
Which LDOs configuration do you recommend us in case we want to use Arm at 972MHz and GPU as well?
Thanks in advance!
Hi joan
ldo bypass allows less processor heating, so it may be recommended
when using gpu/vpu. Linux ldo bypass configuration can be found in function
regulator_allow_bypass() in linux/drivers/regulator/core.c :
Bypass mode means that the regulator is simply passing the input directly to the output with no regulation.
also please check sect.50.7.4 Digital Regulator Core Register (PMU_REG_CORE),
i.MX6DQ RMREG_TARG description
http://cache.freescale.com/files/32bit/doc/ref_manual/IMX6DQRM.pdf
Best regards
igor
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------