Part Number: TPS2546
We are using this USB Charge Port Controller to manage a USB type A receptacle. The ILIM_HI setting is 1.2A for a 1A DCP.
We wish to support portable devices that look for Apple signatures on D+/D- as well as shorted D+/D- per USB BC 1.2 DCP.
When we connect a device (iPhone or static load) we observe the chip change modes from DIVIDER1 to DIVIDER2 with a 2 second pause (VBUS is discharged).
The datasheet explains that the mode change occurs if the load device draws more than 750mA.
The port DCP is configured for 1A so changing to DIVIDER2 mode (2.1A) is not desirable and may confuse the attached portable device.
Can you help us understand why the mode change is happening and why 750mA is the threshold?
Thank you!