1 General description
The PCA9601 is designed to isolate I2C-bus capacitance, allowing long buses to be
driven in point-to-point or multipoint applications of up to 4 000 pF. The PCA9601 is
a higher-speed version of the P82B96 and a higher drive version of the PCA9600
that allows many more Fast-mode Plus (Fm+) slaves on remote daughter cards in
applications with temperature range of 0 °C to 85 °C.
It creates a non-latching, bidirectional, logic interface between a normal I2C-bus and a
range of other higher capacitance or different voltage bus configurations. It can operate
at speeds up to at least 1 MHz, and the high drive side is compatible with the Fast-mode
Plus specifications.
The PCA9601 features temperature-stabilized logic voltage levels at its SX/SY interface
making it suitable for interfacing with buses that have non I2C-bus-compliant logic levels
such as SMBus, PMBus, or with microprocessors that use those same TTL logic levels.
15 mA drive capability over 0 °C to 85 °C at SX/SY allows driving a 5 V Fm+ bus with
470 pF loading.
The separation of the bidirectional I2C-bus signals into unidirectional TX and RX signals
enables the SDA and SCL signals to be transmitted via balanced transmission lines
(twisted pairs), or with galvanic isolation using opto or magnetic coupling. The TX and RX
signals may be connected together to provide a normal bidirectional signal.
2 Features and benefits
• Bidirectional data transfer of I2C-bus signals
• 15 mA SX/SY sink capability yields 5 V Fm+ bus rise time with 470 pF loads
• Isolates capacitance allowing > 400 pF on SX/SY side and 4000 pF on TX/TY side
• 1 MHz operation on up to 20 meters of wire (see AN10658)
• Supply voltage range of 2.5 V to 15 V with I2C-bus logic levels on SX/SY side
independent of supply voltage
• 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
• Low power supply current
• ESD protection exceeds 3500 V HBM per JESD22-A114, and 1400 V CDM per
JESD22-C101
• Latch-up testing is done to JEDEC Standard JESD78 which exceeds 100 mA
• Packages offered: SO8 and TSSOP8 (MSOP8)

3 Applications
• Interface between I2C-buses operating at different logic levels (for example, 5 V and 3
V or 15 V)
• Interface between I2C-bus and SMBus (350 μA) standard or Fm+ standard
• Simple conversion of I2C-bus SDA or SCL signals to multi-drop differential bus
hardware, for example, via compatible PCA82C250
• Interfaces with opto-couplers to provide opto-isolation between I2C-bus nodes up to 1
MHz
• Long distance point-to-point or multipoint architectures