P82B96
Dual bidirectional bus buffer
Rev. 08 — 10 November 2009
Product data sheet
1. General description
The P82B96 is a bipolar IC that creates a non-latching, bidirectional, 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, it can interface to the 350 µA SMBus, to 3.3 V logic devices, and to 15 V
levels and/or low-impedance lines to improve noise immunity on longer bus lengths.
It achieves this interface without any restrictions on the normal I2C-bus protocols or clock
speed. The IC adds minimal loading to the I2C-bus node, and loadings of the new bus or
remote I2C-bus nodes are not transmitted or transformed to the local node. Restrictions
on the number of I2C-bus devices in a system, or the physical separation between them,
are virtually eliminated. Transmitting SDA and 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 bidirectional signal line with
I2C-bus properties.
2. Features
I Bidirectional data transfer of I2C-bus signals
I Isolates capacitance allowing 400 pF on Sx/Sy side and 4000 pF on Tx/Ty side
I Tx/Ty outputs have 60 mA sink capability for driving low-impedance or high capacitive
buses
I 400 kHz operation over at least 20 meters of wire (see AN10148)
I Supply voltage range of 2 V to 15 V with I2C-bus logic levels on Sx/Sy side
independent of supply voltage
I Splits I2C-bus signal into pairs of forward/reverse Tx/Rx, Ty/Ry signals for interface
with opto-electrical isolators and similar devices that need unidirectional input and
output signal paths.
I Low power supply current
I ESD protection exceeds 3500 V HBM per JESD22-A114, 250 V DIP package, 400 V
SO package MM per JESD22-A115, and 1000 V CDM per JESD22-C101
I Latch-up free (bipolar process with no latching structures)
I Packages offered: DIP8, SO8 and TSSOP8
