The ancient Egyptians, Greeks, and Indians were known for
attempting to recreate the “Midas touch,” whereby they
would practice alchemy in their ongoing quest to find the
perfect catalyst to turn lead to gold. Yet they forgot one important
aspect of Midas’ legend. King Midas came to hate wealth and
splendor and started worshipping Pan, the Greek god of nature. Thus,
you could say that Midas came to love all things green.
Catalyst Semiconductor had Pan in mind when it developed its
latest 8-bit general-purpose I/O (GPIO) expander IC for I2C and
SMBus-based applications (see the figure). The CAT9534 is pin- and
function-compatible with the industry-standard CAT9554. Yet while
the chip may have a black case, at one-hundredth the standby power
of the previous generation, your customers will be saving green while
keeping the planet green.
Let’s look at the planet part first. The device provides a standby
mode that sips a mere 1-µA maximum supply current. This translates
to 2.3 to 5.5 µW over the device’s 2.3- to 5.5-V operating range. Pan
would be proud. As for the green savings, the CAT9534 costs $0.83
each in 10,000-piece quantities. I don’t know how many ancient
Greek obols that would equate to, but it’s safe to say not many.
So what does $0.83 buy these days besides less than a quarter of
a gallon of gas? The I/O pins can operate at 2.5, 3.3, and 5 V and up
to 400 kHz. They also can sink up to 25 mA and source up to 10 mA,
and they may be individually configured via configuration registers.
Furthermore, the CAT9534 includes a polarity inversion register, an
interrupt output, and internal power-on reset. It promises to remain
glitch-free during power-up. And, it operates in the industrial temperature
range (–40°C to 85°C).
Applications include white goods like dishwashers and other major
appliances; handheld devices such as cell phones, PDAs, and digital
cameras; data communication devices, such as routers, hubs, and
servers; and other applications using sensors, power switches, LEDs,
pushbuttons, and fans.
The CAT9534 is available in 16-pin small-outline IC (SOIC), thinshrink
small-outline (TSSO), and thin quad flat no-lead (TQFN)
packages that comply with the European Union’s Restrictions on
Hazardous Substances. Samples are available now, with production
quantities available soon.