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TI introduces the industry's smallest single-wire I/O expander

Five-channel output expander reduces required connections by up to 75 percent

Sep 7, 2011

DALLAS, Sept. 7, 2011 /PRNewswire/ -- Texas Instruments Incorporated (TI) (NYSE: TXN) today introduced the industry's smallest single-wire I/O expander with self-timed, single-wire (STSW) technology from Texas Instruments. The TCA5405 allows system designers to control and expand outputs to as many as five, using a single processor general purpose input/output (GPIO). This expander reduces the number of connections needed, thus eliminating 50 percent of the lines versus I2C, and 75 percent compared to a serial peripheral interface (SPI) bus. Download a data sheet and order your samples here: www.ti.com/tca5405-pr.  

This device can be implemented in many design configurations that require a small footprint, such as cell phones, personal digital assistants (PDAs), portable media players, and portable instrumentation devices such as blood glucose meters and insulin pumps.

TCA5405 key features and benefits

  • Easier implementation of port expansion makes it suitable for simple functions, such as chip select (CS) or enable (EN) pins, as well as complex functions like driving LEDs (<20 mA).
  • One-wire protocol-based port expansion in an eight-pin, 2.25-mm2 micro-QFN package makes it the industry's smallest five-channel expander.
  • STSW interface reduces connections by as much as 50 percent versus I2C, and 75 percent versus serial peripheral interface (SPI).
  • Standby current consumption, which is 20 percent lower than the nearest competitor, supports power-savvy, high-performance applications with 2 uA and a drive strength current of +20 mA.


Tools and support

TI offers a variety of free tools and support to speed development time:


Availability and pricing

The TCA5405 comes in an eight-pin, 2.25-mm2 RUG micro-QFN package. It is in full production now and is available from TI and authorized distributors with the suggested resale price of $0.65 in quantities of 1,000.

Learn more about TI's I2C portfolio:


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SOURCE Texas Instruments Incorporated