P82B96

The P82B96 is a bipolar IC that creates a non-latching, bi-directional, logic interface between the normal I2C-bus and a range of other bus configurations. It can interface I2C-bus logic signals to similar buses having different voltage and current levels.

For example P82B96 can interface to the 350 mA SMB bus, to 3.3 V logic devices, and to 15 V levels and/or low impedance lines to improve noise immunity on longer bus lengths.

P82B96 achieves this interface without any restrictions on the normal I2C protocols or clock speed. The IC adds minimal loading to the I2C node, and loadings of the new bus or remote I2C nodes are not transmitted or transformed to the local node. Restrictions on the number of I2C devices in a system, or the physical separation between them, are virtually eliminated. Transmitting SDA/SCL signals via balanced transmission lines (twisted pairs) or with galvanic isolation (opto-coupling) is simple because separate directional Tx and Rx signals are provided. The Tx and Rx signals may be directly connected, without causing latching, to provide an alternative bi-directional signal line with I2C properties.