The DS2488 is a simple bridge device that with a single dedicated contact on each side of the bridge enables up to 512kbps pass-through communication, power delivery for battery charging, small message exchange, and state reporting between two microcontroller-based subsystems. An example application is true wireless stereo (TWS) earbuds containing a Bluetooth® Audio SoC and the microcontroller operated case that holds and charges the earbuds. In this scenario, the DS2488 would reside in earbuds alongside the SoC, and the charge case microcontroller would communicate with the DS2488 from a single dedicated pin. All of this is enabled with the flexibility of the 1-Wire® interface, which is used to operate each of the two independent I/O ports, IOA and IOB. To enable device operation between two connected controllers, each of these two DS2488 1-Wire interfaces has access to a 64-bit factory-programmed ROM ID, an 8-byte buffer to transmit small messages, and registers for device configuration, status, and control of three open-drain GPIO pins. Through a configuration setting a bidirectional, high-speed 512kbps pass-through mode is enabled, which enables large data transfers between the two connected microcontrollers.
For communication between IOA and IOB, the DS2488 has a maximum operating voltage of 3.63V. But to support a special mode of power delivery from the subsystem connected to the IOA side to the subsystem connected to the IOB side, the device is 5V tolerant and goes into the power delivery state when 4V to 5V (nom) is applied to IOA. In this mode, an additional DS2488 output pin is used to control an external transistor for power delivery to IOB-side electronics, such as a battery charger.