BQ25895M: BQ25895M DSEL D+ D- pin configuration.

Srishtik Bhandarkar

Part Number: BQ25895M

Hi,

I am using BQ25895M with a generic 5V Vbus input source and not a USB 5V input source.

How do I connect D+ D- and DSEL pins?

I am not using any USB handshake protocol as it is not a USB charger I am plugging into Vbus. It is a regular DC-DC switching regulator set to 5V output connected to Vbus input.

Should I leave them open/floating or do I need to connect them anywhere?

Thanks,

Srishtik.

over 1 year ago

0 James Steenbock over 1 year ago

TI__Genius 17535 points

Hi Srishtik,

The D+ and D- pins can be left floating or be shorted together. If they are left floating, the input will be detected as an "Unknown adapter" and your input current limit will be set to 500mA. If the D+ and D- pins are shorted together you will detect a DCP input and the input current limit will be set to 3.25A.

The ILIM pin can be used to set a hardware-based input current limit for additional safety. The charger will use the lower of the two input current limits between the ILIM pin and the IINLIM register setting. This function can be used to protect your adapter from overloading conditions even if the input detection allows for higher currents via software settings.

Regards,

James

0 Srishtik Bhandarkar over 1 year ago in reply to James Steenbock

Prodigy 50 points

Thanks James.

I had one more doubt. What about DSEL pin? Should be left floating or connected anywhere?

Thanks,

Srishtik.

0 James Steenbock over 1 year ago in reply to Srishtik Bhandarkar

TI__Genius 17535 points

Hi Srishtik,

The DSEL pin needs to be connected to a logic rail via 10kOhm pull-up resistor. Here is the pin description from Section 6 of the datasheet as a reference:

Regards,

James

Power management

Power management forum

BQ25895M: BQ25895M DSEL D+ D- pin configuration.