This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

BQ25792: I2C control of TPS25751 and EV2400

Part Number: BQ25792
Other Parts Discussed in Thread: TPS25751, , EV2400

Tool/software:

Dear Sirs and Madams,

We are considering the combination of BQ25792 and TPS25751.

We connected the EV2400 to the I2C line and tried to write to the BQ25792 from BQ studio, but the registers were not updated.

The I2C SCL and SDA also remain 'H'.

The connection configuration is as follows:

When we connect the EV2400 to the I2C line and open BQ Studio,  the screen will show “Device ACK OK.”

In this state, I changed "Update Mode" to "Manual" and pressed the "Write Register" button, but the register was not changed and the I2C SCL and SDA remained at 'H'.

Is it not possible to write to the BQ25792 from the EV2400 when connected to the TPS25751?

Regards,

Masashi

  • HI Masashi,

    EV2400 is a primary (formerly called master).  I have never tested with 2 primaries on the I2C bus.  The BQ25792 registers reset to defaults if the WD timer expires.  Also IINDPM register is clamped by the ILIM_HIZ resistor divider setting.

    Regards,

    Jeff  

  • Hi Masashi, 

    The TPS25751 does not support multi-master on the I2C lines. The TPS25751 has integrated I2C control for the BQ25792 configuring all necessary registers during sourcing, sinking, power role swaps, hard resets, and detach events. 

    To configure additional BQ registers while connected to the TPS25751, an MCU would be needed to send a 4CC command to the PD 'I2Cw'. 

    Best Regards, 

    Aya Khedr 

  • Hello Everyone,

    We understood that the BQ2579x does not support I2C multi-master.

    We will consider how to use the TPS25751 as the master using the 4CC command.

    Regards,

    Masashi