ADuM1252/3 Ultra-Low Power I²C Isolators

ADI's ADuM1252 offers two bidirectional, open-drain channels for applications, such as I²C, that require data to be transmitted in both directions on the same line. In comparison, the ADuM1253 offers two open-drain channels, one unidirectional and one bidirectional, for applications, such as I²C, that require data to be transmitted in both directions on the same line but have a unidirectional clock. On both devices, side one outputs prevent latch-up action with special buffers that regulate the logic-low voltage at 0.64 V, and the input logic-low threshold is at least 50 mV lower than the output logic-low voltage. Side two features conventional buffers that do not regulate logic-low output voltage.

The ADuM1252 and ADuM1253 feature independent 1.71 V to 5.5 V supplies on both sides one and two of the isolator. The devices operate up to 2 MHz. The ultra-low standby current of 21 μA per side is ideal for battery-operated systems.

The devices provide a disturbance-free bus connection for hot-plug connections on side two by pre-charging the bus pins and monitoring the bus state for an idle bus or an I²C stop condition before connecting sides one and two.

The ADUM1252SEVKIT# (EV kit) is a fully assembled and tested circuit board that demonstrates the features of the ADuM1252. The kit can be used to evaluate the functionality and electrical performance of the ADuM1252. Two independent power supplies power the EV kit. The ADuM1252S EV kit can also be used to evaluate the ADuM1253.