2018 Microchip Technology Inc. Product Brief DS40002003A-page 1
Description
The mXT449T-AT/mXT449T-AB 1.0 uses a unique charge-transfer acquisition engine to implement Microchip’s patented
capacitive sensing method. Coupled with a state-of-the-art CPU, the entire touchscreen sensing solution can measure, classify
and track a number of individual finger touches with a high degree of accuracy in the shortest response time. The mXT449T-AT/
mXT449T-AB 1.0 allows for both mutual and self capacitance measurements, with the self capacitance measurements being
used to augment the mutual capacitance measurements to produce reliable touch information.
maXTouch
®
Adaptive Sensing Touchscreen
Technology
• Up to 32 X (transmit) lines and 20 Y (receive) lines
• A maximum of 448 nodes can be allocated to the
touchscreen
• Touchscreen size 7.62 inches (16:9 aspect ratio),
assuming a sensor electrode pitch of 6 mm. Other
sizes may be possible with different electrode pitches
and appropriate sensor material
• Multiple touch support with up to 16 concurrent
touches tracked in real time
Automotive Applications
• AEC-Q100 Qualified
• Developed following Automotive SPICE
®
Level 3
certified processes
• CISPR-25 compliant (for both mutual and self
capacitance measurements)
Touch Sensor Technology
• Discrete/out-cell support including glass and PET film-
based sensors
• On-cell/touch-on display support including TFT, IPS
and OLED
• Support for standard (for example, Diamond) and
proprietary sensor patterns (review of designs by
Microchip recommended)
Front Panel Material
• Works with PET or glass, including curved profiles
(configuration and stack-up to be approved by
Microchip)
• Glass 0.5 mm to 2.0 mm (dependent on screen size,
touch size, configuration and stack-up)
• Plastic 0.2 mm to 3.0 mm (dependent on screen size,
touch size, configuration and stack-up)
Touch Performance
• Moisture/Water Compensation
- No false touch with condensation or water drop up
to 22 mm diameter
- One-finger tracking with condensation or water
drop up to 22 mm diameter
• Glove Support
• Mutual capacitance and self capacitance
measurements supported for robust touch detection
• Noise suppression technology to combat ambient and
power-line noise
- Up to 240 Vpp between 1 Hz and 1 kHz
sinusoidal waveform
- Up to 20 Vpp between 1 kHz and 1 MHz
sinusoidal waveform
• Scan Speed
- Up to 190 Hz one finger reporting rate (subject to
configuration)
- Typical report rate for 10 touches 60 Hz (subject
to configuration)
- Initial touch latency <25 ms for first touch from idle
(subject to configuration)
- Configurable to allow for power and speed
optimization
On-chip Gestures
• Reports one-touch and two-touch gestures
Keys
• Up to 32 nodes can be allocated as mutual
capacitance sensor keys (subject to other
configurations)
• Adjacent Key Suppression (AKS) technology is
supported for false key touch prevention
- Multiple-finger glove touches up to 1.5 mm
thickness (subject to stack-up design)
- Single-finger glove touch up to 5 mm thickness
(subject to stack-up design)
mXT449T-AT/mXT449T-AB 1.0
maXTouch 448-node Touchscreen Controller
Product Brief