Cypress's Dhwani Vyas put it best, "Finally [we] have the part I have
been waiting for!" He was referring to the company's new Gen4 family of
touchscreen controllers that are the first to feature an ARM 32-bit
core, along with proprietary LCD noise cancellation technology called
DisplayArmor that eliminates the need for an extra shield layer of glass
and its associated air gap, thereby reducing display thickness by up to
1 mm and lowering overall cost and weight.
Other key features of the new Gen4 TrueTouch include a fast refresh
rate of 400 Hz, a 1-kHz scan frequency, and accuracy of 0.2 mm (useful
for Asian characters), a low active power consumption of 2 mW and a deep
sleep mode that pulls only 1.8 microwatts. Wake-up is provided via an
address match on the COM port.
To address charger noise, Gen4 relies upon Cypress's established 10V
S8 process technology to give a signal-to-noise ratio of 10V Tx.
While the overall performance figures rank high, one of the
interesting angles to the Gen4 is the mentality behind its derivation.
According to Vyas, who's vice president of Cypress's User Interface
Business Unit, the device display ecosystem is fraught with challenges.
OEMs want thinner displays for their systems, but thinner displays
means putting the touch sensor closer to the ITO layers of the LCD,
making the sensor more susceptible to noise. The touch sensor could ask
the LCD maker to reduce the noise, or the LCD maker could ask the
display glass maker to put in an extra shield layer, but this costs an
So, what to do? Cypress decided to cut all the back and forth and
just take noise out of the equation. "We [as an ecosystem] can't keep
complaining about display noise," said Vyas, "instead we just fixed it."
With proprietary noise cancellation algorithms, which Vyas would not
describe beyond hinting at techniques used in noise-cancelling
headphones, Cypress's Gen4 eliminates the need for a 0.5-to 0.7-mm glass
layer, as well as the associated 0.3-mm air gap to reduce the display
thickness, without compromising noise performance.
Figure: Cypress's Gen4 TrueTouch's Display Armor LCD noise
cancellation technology allows removal of a glass shield and associated
airgap, saving up to 1 mm in display thickness.
For more on display noise the associated topic of charger noise, Cypress has produced an interesting paper called, "Investigating display and charger noise: Projected capacitance evolving," that goes into more detail.
Back to the Gen4. Other key features of the new lineup include:
Small size: Up to 40 I/Os for mobile phone applications, with support
for up to four standalone CapSense button. IP-67 waterproofing support
and dynamic switching between self- and mutual-capacitance sensing
How soon can you get hold of one?
You'll have to get in line: The Gen4 controllers are available now only
to lead customers, to which Cypress expects to deliver volume production
by the end of 2011.
Packaging: The family will be available in a 44-pin 5x5 QFN with 31
sense I/Os, a 48-lead 6x6 QFN package with 35 sense I/Os, a 49-ball
WLCSP package with 36 sense I/Os, and a 60-ball WLCSP package with 40
sense I/Os. The WLCSP (Wafer-Level Chip-Scale Packages) devices have a
footprint of only 3.8 mm x 3.8 mm.
For more on the new Gen4 devices, go to touch.cypress.com.
Given that Cypress believes figures from DisplaySearch that the
touchscreen market will grow 200% to $23 billion by 2017, they think you
shouldn't mind waiting a few weeks to jump on the touchscreen bandwagon
with a really good device. I'm inclined go agree with them.
What do you think?
For the latest on sensors, see:
Modern sensors greatly enhance consumer-elecronics-system performance
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