Accessory Power & Communication Interface
The AS3442 POW:COM host is a digital power and communication chip. The device is utilizing two signal lines for data transmission and power transfer to an accessory. The device is equipped with a standard I2C interface for data exchange with its client device (AS3447), an interrupt input as well as an enable pin. Combining these features together the device is ideally suited for True Wireless (TWS) headsets applications to reduce number of interconnects between charger cradle and earbud. A user-friendly I2C communication interface is assembled on both boards. The technical documentation and the software comes conveniently in one box with the evaluation board.
AS3447 - Power & Communication Interface
The AS3442/47 allows to extend the functionality of the two wire connection to enable charging and simultaneous communication to the earpiece. The MCU inside the charger cradle can request data from the earphone while the charging process is on-going and vice versa. In order to operate the system two chips per side are necessary. The master device (AS3442), which is typically located in the charger cradle, and a client device (AS3447), which is located in the accessory. The master device features an I2C interface typically connected to a MCU inside the charger cradle to initiate the single wire connection to the client device. Furthermore it enables readout of AS3442 register and I2C sensors which are connected to the AS3442 I2C master interface. An interrupt signal line is available to detect status changes on GPIOs or if communication is interrupted. The client device features besides the I2C master interface up to 5 GPIOs which can be controlled via the host MCU. An interrupt input pin is available whose status signal is
also transferred to host MCU accordingly.