• I2C to Parallel Port Expander
• Wide Power Supply Voltage Range of 1.65-V to 5-V
• Low Standby-Current Consumption of 3μAMax
• Open-Drain Active-Low Interrupt Output
• 5-V Tolerant I/O Ports
• 400-kHz Fast I2C Bus
• Polarity Inversion Register
• Address by Three Hardware Address Pins for Use of up to Eight Devices
• Latched Outputs With High-Current Drive Capability for Directly Driving LEDs
• Latch-Up Performance Exceeds 100mA Per JESD78, ClassII
• ESD Protection Exceeds JESD22
  • 2000-V Human-Body Model (A114-A)
  • 1000-V Charged-Device Model (C101)

• Servers
• Routers (Telecom Switching Equipment)
• Personal Computers
• Personal Electronics (For Example, Gaming Consoles)
• Industrial Automation
• Products With GPIO-Limited Processors

The TCA9535 is a 24-pin device that provides 16 bits of general purpose parallel input/output (I/O) expansion for the two-line bidirectional I2C bus or (SMBus) protocol. The device can operate with a power supply voltage ranging from 1.65 V to 5.5 V. I/O expanders, such as the TCA9535, provide general-purpose remote I/O expansion for most microcontroller families via the I2C interface, providing a simple solution when additional I/Os are needed for switches, sensors, push-buttons, LEDs, fans, and other similar devices.

The TCA9535 consists of two 8-bit Configuration (input or output selection), Input Port, Output Port, and Polarity Inversion (active-high or active-low operation) registers. At power on, the I/Os are configured as inputs. The system master can enable the I/Os as either inputs or outputs by writing to the I/O configuration bits.

The TCA9535 is identical to the TCA9555, except that the TCA9535 does not include the internal I/O pull-up resistor, which requires pull-ups/pull-downs on unused I/O pins when configured as an input and undriven.