1 Features

. I2C to Parallel port expander

. Operating power-supply voltage range of 1.65 V to

5.5 V

. Allows bidirectional voltage-level translation and

gpio expansion between 1.8-V, 2.5-V, 3.3-V, and

5-V I2C bus and P-ports

. Low standby current consumption of 1 μA

. 5-V Tolerant I/O ports

. 400-kHz Fast I2C bus

. Hardware address pin allows two TCA6408A

Devices on the same I2C/SMBus bus

. Active-low reset ( RESET) input

. Open-drain active-low interrupt ( INT) output

. Input and output configuration register

. Polarity inversion register

. Internal power-on reset

. Power up with all channels configured as inputs

. No glitch on power up

. Noise filter on SCL and SDA inputs

. Latched outputs with high-current drive maximum

capability for directly driving LEDs

. Latch-up performance exceeds 100 mA Per JESD

78, class II

. Schmitt-trigger action allows slow input transition

and better switching noise immunity at the SCL

and SDA inputs

. ESD Protection exceeds JESD 22

. 2000-V Human body model (A114-A)

. 1000-V Charged-device model (C101)

2 Applications

. Servers

. Routers (telecom switching equipment)

. Personal computers

. Personal electronics (gaming consoles)

. Industrial automation

. Products with GPIO-limited processors

3 Description

The TCA6408A is a 16-pin device that provides 8-

bits of general purpose parallel input/output (I/O)

expansion for the two-line bidirectional I2C bus (or

SMBus) protocol. This device can operate with a

power supply voltage ranging from 1.65 V to 5.5 V

on both the I2C bus side (VCCI) and on the P-port side

(VCCP). This allows the TCA6408A to interface with

next-generation microprocessors and microcontrollers

on the SDA/SCL side, where supply levels are

dropping down to conserve power. In contrast to

the dropping power supplies of microprocessors and

microcontrollers, some PCB components such as

LEDs remain at a 5-V power supply.

The device supports both 100-kHz (Standard-mode)

and 400-kHz (Fast-mode) clock frequencies. I/O

expanders such as the TCA6408A provide a simple

solution when additional I/Os are needed for switches,

sensors, push-buttons, LEDs, fans, and so forth.