• Operating Power-Supply Voltage Range of 1.65 to 3.6 V
• Allows Bidirectional Voltage-Level Translation and GPIO Expansion Between 1.8-V, 2.5-V, 3.3-V GPIO Port and
  • 1.8-V SCL/SDA
  • 2.5-V SCL/SDA
  • 3.3-V SCL/SDA
  • 5-V SCL/SDA
• Standby Current Consumption of < 2 µA at 1.8 V
• Active Current Consumption of:
  • < 2 µA at 1.8-V 100-kHz Clock
  • < 5 µA at 1.8-V 400-kHz Clock
• 100-kHz, 400-kHz Fast Mode
• Internal Power-on-Reset and Watchdog Timer
• Fail Safe I2C, INT, and RESET lines
• Noise Filter on SCL/SDA and Inputs
• Active-Low Reset (RESET) Input
• Open-Drain Active-Low Interrupt (INT) Output
• Programmable Pull-up/Pull-down Resistors for GPIO Inputs
• Programmable Edge Detection for Generating Interrupts
• Interrupt Latching
• Software Reset
• Input/Output Direction Register
• Power Up With All Channels Configured as Inputs
• Latched Outputs With High-Current Drive Maximum Capability for Directly Driving LEDs
• Latch-Up Performance Exceeds 100 mA Per JESD 78, Class II
• ESD Protection Exceeds JESD 22
  • 2000-V Human-Body Model (A114-A)
  • 1000-V Charged-Device Model (C101)
• Package: µCSP 16 Ball (4 x 4), 2.0 mm x 2.0 mm, 0.5-mm pitch, 0.55-mm height

• Personal electronics (e.g. Smartphones, Gaming Consoles, Personal Computers)
• Servers, Routers (Telecom Switching Equipment), Industrial Automation
• Products with GPIO-Limited Processors

TCA7408 is an 8-bit I/O expander for the two-line bidirectional bus (I2C) and is designed to provide general-purpose remote I/O expansion through the I2C interface.

The major benefit of this device is its wide VCC range. It can operate from 1.65 V to 3.6 V on the GPIO-port side and 1.65 V to 5.5 V on the SDA/SCL side. This allows the TCA7408 to interface with next-generation microprocessors and microcontrollers on the SDA/SCL side, where supply levels are dropping down to conserve power.

The bidirectional voltage-level translation in the TCA7408 is provided through VCCI. VCCI should be connected to the VCC of the external SCL/SDA lines. The voltage level on the GPIO-port of the TCA7408 is determined by VCCP.

At power on, the I/Os are configured as inputs; however, the system master can enable the I/Os as either inputs or outputs by writing to the I/O direction bits. The data for each input or output is kept in the corresponding Input or Output register. All registers can be read by the system master.

TCA7408 has open-drain interrupt (INT) output pin that goes LOW when the input state of a GPIO-port changes from the input-state default register value. The device also has an interrupt masking feature by which the user can mask the interrupt from an individual GPIO-port.