BQ25672EVM: BQ25672EVM

Thanks, Jeff.

H Jeff, If I send you a pdf of my BQ25672 design would you review it?

Dan

Hi Dan,

The BQZ file must be saved in the BQSTUDIO config folder.

Regards,

Jeff

Yes.

Regards,

Jeff

BRIDGE-SCHEMATIC-REV6.pdf

Thank you.

Schematic attached.

Hi Jeff,

I tried running the BQ25672EVM with the BQ25798.bqz file using the EV2400 and I get a message saying the file is not compatible, proceed at your own risk.

So, I proceeded.

I get a screen with two tabs, nothing like what is described in the EVM datasheet.

The screen looks like this:

Can you help me figure out what to do from here??

Thanks,

Dan

Hi again,

I got things working to the point where I can R/W I2C registers.

Is that all the STUDIO does?

I have to set ALL the registers to what I need??

Dan

Hi Jeff,

I was able to communicate using the EV2400, 8-bit I2C address 0xD7 for reads (7-bit 0x6B)

I purchased a USB2ANY just to see how it works.

I cannot get any communication going.

I put a jumper on JP31

I selected BQ25672 from the cloud app.

If I goto the register map and click on the "gear" it says the device is the BQ25790??

Even though I selected the BQ25672

Any thoughts would be appreciated, I really want to get the USb2ANY working.

Thanks,

Dan

One more little piece of info.

If I put a scope probe on the I2C clock line and click "connect to EVM", nothing happens.

(USB2ANY)

When I do this with the EV2400, I see clock signals.

Dan

Hi again Jeff,

You've been a great resource, thanks!

I now have most things working on the EVM.

I have two sources, either of which can be used to power our system or charge the battery.

The one thing I am having trouble with is OTG mode.

Our goal is to have the battery drive VIN2 and power the system in the case both external supplies are down.

I tried setting the EN OTG bit in the GUI, that did not work.

I am wondering if I need to enable or set something else in order for this mode to work?

On the OTG config screen I have the voltage set to 5V, the current set to 2A and the battery discharge set to 3A

Thanks,

Dan

Hi Jeff,

So I turned off my power supplies, then enabled OTG, then tried to select EN ACDRV2, the GUI would mot allow that.

Dan

Hi Dan,

That should work.  I don't use the charger GUI often.  I will go to the lab and test shortly.

Regards,

Jeff

Thank you!

Hi Dan,

It worked me in both BQSTUDIO and ChargerGUI.  Keep in mind that when the WD timer expires, EN_OTG bit gets reset to 0.  Could that be the issue?  Are the status and flag registers reporting anything that could cause a problem?

Regards,

Jeff

Hi,

The timer is probably the reason I could not select the EN ACDRV2, however even when I restarted the timer and selected OTG, then EN ACDRV2, there was no voltage present on the VBUS.

Is there any thing else I should have to select or deselct?

Also, the AC DRV is at 0V?

The AC DRVs only turn on when my external power supplies are on

Hi Jeff,

I have a few more questions I hope you can help with. These come from my customer.

We have two sources of input power, a stepped down 28V supply (28V->7V) and USB power. These two comprise 

our 2 power inputs to the BQ25672as you've seen on the schematic I sent you.

If one supply goes down, the other will supply power to the BQ part, charger our battery and provide Vsys.

If both supplies are down the battery will provide power to Vsys and optionally power the 5V USB rail via the OTG function.

I've seen all this work on the eval board.

1) It seems some of what I described is "automatic" and other functions require control of the registers. For example, the switching from

one power supply to the other happens automatically, but switching back to a supply that had gone down and returned requires register manipulation. Can you explain automatic vs manual features in a little detail?

Here are some other requirements that may mean we need something like a TUSB320LAIR chip, I'm not sure. In my schematic I show this chip, does it look like I am using it correctly?

2) When connected to a USB host, the Bridge needs to be able to receive power from the host and act as a UFP (Upstream Facing Port) so it an appear to be a USB drive

3)\ When a USB Thumb drive or other USB accessory (acting as an USP) is attached to the Bridge, the bridge needs to be able to power the USB accessory and communicate with it such that the bridge is acting as a DFP (Downstream Facing Port)

Different cable harnesses will be used to facilitate the different USB connects that are possibly, ie USB C M/F and USB A/B.

Any guidance s appreciated,

Dan

Hi Jeff,

So given my customers need to handle UFP, DPF and DRP, is my design insufficient?

Dan

Hi Jeff,

Even with the TUSB320?

Can you suggest an architecture that would work?

Are you up for a phone call some time?

Dan

Can you connect me with an USB320 apps engineer that I can show my schematic to?

Hi Dan,

I will move this post to that group's forum.

Regards,

Jeff

Thanks Jeff.

Can you explain exactly what the USB interface on the BQ25672 does?

Jeff,

What group did you move this to?

I did not get a notification of any type.

Dan

Hi Dan,

The charger D+/D- pins only communicate with the legacy USB BC1.2 port or a few HVDCP adapters for the first 2 seconds after power up.  Then those pins go HiZ.  

I moved to the group that supports TUSB320 questions.  If you don't get a response, I suggest creating a new post with TUSB320 as the part number.

Regards,

Jeff