can modify buck3 output from 3.3 to 1.8?
Forums › Devices › OSD32MP15x › can modify buck3 output from 3.3 to 1.8?
Tagged: OSD32MP15x
- This topic has 3 replies, 2 voices, and was last updated 3 years, 7 months ago by
rishi@smufsbio.com.
- AuthorPosts
- April 3, 2021 at 9:08 am #11426
Hi there,
I am trying to make battery based design, just wondering modifying VINOK_Rise from 3.5 to 3.3V is enough. Or i should also switch Buck3 output from 3.3 to 1.8 as well.
I am confused as in the osd datasheet seems like you discourage to modify any outputs of pmic regulators.
[Section 7.6]
“.. While some of the output voltages of the regulators can be adjusted, they
should not be adjusted….”.
The regulators which i should not modify includes buck3?Thanks, Rishi
- April 3, 2021 at 6:17 pm #11427
Hi All,
I am sorry probably i posted my question as soon as it came to my mind….
Reading further clarified i think 7.6.11 table clearly shows what should NOT be modified.Thanks, Rishi
- April 5, 2021 at 10:59 am #11430
Rishi,
Based on the battery output voltage, you might have to configure VDD to be 1.8V instead of 3.3V. This is recommended if you are using a battery according to the PMIC datasheet. Please take a look at the Power System Overview for OSD32MP1: https://octavosystems.com/app_notes/osd32mp1-power-system-overview/.
Best,
Neeraj
- April 9, 2021 at 9:46 pm #11442
Hi Neeraj,
Thanks, After some load testing we decided to use our external power supply in our initial prototype.
Yes you are right we will use VDD 1.8 but we still need 5 and 3.3 lines.As our 5V load is around 400mA and our 3.3 load is USB hub and emmc chips which is around 250mA.
So after testing for like 20-30 minutes voltage was dropping a lot, 5.2 V was going down to 4.8~4.9V from BST_OUT and 3.3V was going down to 2.7~2.8V from LDO2.
So to be on safer side we decided to have our own external supply.
Thanks, Rishi
- AuthorPosts
- You must be logged in to reply to this topic.