2012 Microchip Technology Inc. Advance Information DS41659A-page 1
FEATURES
• Capacitative Proximity Detection System:
- High Signal to Noise Ratio (SNR)
- Adjustable sensitivity
- Noise Rejection Filters
- Scanning method actively optimized to
attenuate strongest noise frequencies
- Automatic calibration with optional user
presets
- Dynamic threshold management adjusts
sensitivity of sensor based on the level of
environmental noise
- Constant press calibration tracks the
expected offset when the sensor is pressed
and adjusts the threshold to automatically
achieve the best press/release behavior
- User-defined "minimum shift" values specify
the lowest amount of signal change to
activate a state transition. Automatic
thresholds never decrease below these
settings.
- Automatic Environmental Compensation
• No Required External Components
• Low-Power mode: Highly Configurable
Low-Power mode
- 1ms to 4s Sleep interval between sensor
samples
• Response Time as Low as 10 mS
• Hardware Error Detection notifies if either sensors
is shorted to V
DD, VSS, or the other sensor
• Operating Voltage Range: 1.8V to 3.6V
• Operating Temperature: -40
o
C to +85
o
C
GENERAL DESCRIPTION
The Microchip mTouch™ MTCH112 Dual Channel
Proximity/Touch Controller provides an easy way to
add proximity and/or touch sensor detection to any
application. The device implements either two
capacitive sensors or one sensor and one active guard
driver. The optional device configuration through I
2
C™
allow presets to be loaded in a production environment.
Automatic calibration routines are used by default to
choose the best options, so user configuration is not
required.
The MTCH112 uses a sophisticated optimization
algorithm to actively eliminate noise from the signal.
While the noise level is being measured, the
requirements for a proximity or touch detection are
updated to reflect the degree of uncertainty in the
readings. When a press is detected for the first time,
the threshold is automatically calibrated to choose a
smart threshold for the ‘release’ and next press. This
creates a system that dynamically optimizes the signal-
to-noise ratio for its environment.
PACKAGE TYPE
The device is available in 8-lead SOIC and DFN.
FIGURE 1: 8-PIN SOIC, DFN DIAGRAM
FOR MTCH112
TABLE 1: 8-PIN DESCRIPTION
Name
8-Pin SOIC
and DFN
Description
V
DD 1 Power Supply Input
MTO/INT 2 Detect Output (Active-Low)
Notification Interrupt Pin
MTI0 3 Proximity/Touch Sensor
Input
RESET
4 Device Reset (Active-Low)
SDA 5 I
2
C™ Data
SCL 6 I
2
C™ Clock
MTI1/
MTGRD0
7 Proximity/Touch Sensor
Input and Active Guard
Shield for MTI0
V
SS 8 Ground Reference
MTI0
RESET
VDD
MTO/INT
VSS
MTI1/MTGRD0
SDA
SCL
1
2
3
4
5
6
8
7
SOIC, DFN
MTCH112
Dual Channel Proximity Touch Controller Product Brief
MTCH112
