Project

General

Profile

Issue #2011

Find a public version of the MAX77693 datasheet / reference manual

Added by Denis 'GNUtoo' Carikli 3 months ago. Updated about 2 months ago.

Status:
New
Priority:
Normal
Assignee:
-
Category:
-
Target version:
-
Start date:
02/24/2020
Due date:
% Done:

0%

Estimated time:
Resolution:
Device:

History

#1

Updated by Denis 'GNUtoo' Carikli 3 months ago

This is needed to at least understand better the USB OTG current limits

#2

Updated by Denis 'GNUtoo' Carikli 3 months ago

  • Subject changed from Find a public versin of the MAX77693 datasheet / reference manual to Find a public version of the MAX77693 datasheet / reference manual
#3

Updated by Fil Lupin 2 months ago

Denis 'GNUtoo' Carikli wrote:

This is needed to at least understand better the USB OTG current limits

In addition to the Kurtis suggestion (https://datasheets.maximintegrated.com/en/ds/MAX774-MAX776.pdf), this doc https://datasheets.maximintegrated.com/en/ds/MAX77818.pdf does seems more complete and has perhaps similarities with what you search for?

#4

Updated by Denis 'GNUtoo' Carikli 2 months ago

This looks like a power management IC that can be used on smartphones.

It also has battery gauge functionalities.

I've looked quickly at the datasheet and that chip has the limit documented through OTG_ILIM in the REVERSE BOOST section of page 14. It also emmits an interrupt when the current limit is attained.

What we could also do is try to find where is the OTG_ILIM register on that chip, and try to understand if the MAX77693 could possibly have something like that, and find its location.

What makes it tricky is that the bootloader could also potentially setup some of the registers, which means that if we ignore that some register that can change the current limit may exit, the information we could gain would specific to a set of devices only and might not always be applicable to all the devices having that chip.

Though if any bootloader has a command to change the limits, we could probably very easily find which register it changed.

If we manage to find such potential register, then we could try to find the over current interrupt as well and go to some hackerspace that has a current sink (and if it's supported by Sigrok we could even script it) in order to find the values. As we only need to do that once for that chip, it makes more sense to try to use one at a hackerspace.

#5

Updated by Denis 'GNUtoo' Carikli 2 months ago

Page 68 (CHG_CNFG_02 Register Bit Description (0xB9)) we have the OTG_ILIM register for the MAX77818.

We now need to try to diff the 2 chips through all the infos we have.

I've not found any (upstream) drivers for the max77818 yet though. So maybe I missed it or maybe there are some in downstream kernels.

#7

Updated by Kurtis Hanna 2 months ago

Found someone mention that they had access to the datasheet and asked them if they could provide us with a copy: https://github.com/freedesktop/drm-misc/commit/e8614292cd41971b54e60188d4e99abdc8695073#commitcomment-38213384

#8

Updated by Fil Lupin 2 months ago

Seems not possible anymore :(

#9

Updated by Jessica Fowlkes about 2 months ago

  • File IMG_1586228913373.jpg added
#10

Updated by Denis 'GNUtoo' Carikli about 2 months ago

  • File deleted (IMG_1586228913373.jpg)
#11

Updated by Denis 'GNUtoo' Carikli about 2 months ago

For the record, I've deleted the image as it looked like a picture of a text message (about some life wounds) on a smartphone. The text had nothing to do with this bugreport. I also locked the associated account. The picture had very few metadata.

Also available in: Atom PDF