SLUSF18A October 2023 – December 2023 BQ25638
PRODUCTION DATA
Refer to the PDF data sheet for device specific package drawings
BQ25638 uses I2C compatible interface for flexible charging parameter programming and instantaneous device status reporting. I2C is a bi-directional 2-wire serial interface. Only two open-drain bus lines are required: a serial data line (SDA), and a serial clock line (SCL).
The device has 7-bit I2C address 0x6B, receiving control inputs from a host device such as a micro-controller or digital signal processor through register addresses defined in the Register Map. The host device initiates all transfers and the charger responds. Register reads outside of these adresses return 0xFF. When the bus is free, both SDA and SCL lines are HIGH.
The I2C interface supports standard mode (up to 100 kbits/s), fast mode (up to 400 kbits/s) and fast mode plus (up to 1 Mbits/s.) These lines are pulled up to a reference voltage via pull-up resistor. The device I2C detection thresholds support a communication reference voltage between 1.2V - 5V.
Due to the ultra low IQ when the device operates in low power mode, it is necessary to use an increased timing between I2C read commands on the I2C bus when operating in fast mode or fast mode plus. The recommended minimum tbuf (bus free time between a STOP and START condition) depends on the I2C mode: