STM8T143 STMicroelectronics, STM8T143 Datasheet - Page 15

• Manufacturer Part Number: STM8T143
• Description: Single-channel capacitive sensor for touch and proximity detection
• Manufacturer: STMicroelectronics

STM8T143
5
5.1
STM8T143 processing
The STM8T143 device is designed to ensure reliable operation whatever the environment
and operating conditions. To achieve this high level of robustness, dedicated processing
have been implemented:
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Automatic electrode tuning (AET)
AET is a sophisticated technology implemented in the STM8T143 device. It optimizes the
performance of the device in a wide range of applications and environmental conditions.
AET algorithm automatically adjusts the internal C
optimise system performance. Please refer to:
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The principle is to select an internal C
predefined range of AET target value ± 256 burst counts.
At device startup, C
target value". Then, the EPCC hardware subtracts an increasing capacitance value until a
"AET target value" is reached. During normal device operation, the EPCC hardware
subtracts from the electrode capacitance (C
determined during the calibration phase.
This automatic system adaptation allows the same burst count number to be reached
regardless of the application electrode and surrounding.
The AET gain can be adjusted by selecting the gain target value through the “Gain target”
option bits.
The AET algorithm is executed whenever the device starts-up and during device operation
when the reference exits burst count range.
During the AET processing (t
refer to
reported and the internal C
streaming
Automatic electrode tuning (AET)
Signal and reference calibration
Detection and release thresholds
Dynamic calibration (DYCAL)
Environment control system (ECS)
Debounce filter
Host control input
Table 18: Internal CS value
capacitance
Table 19: Implemented EPCC values (pF)
Table 7: Data streaming
mode).
S
is selected to reach the nearest signal burst count value to a "gain
S
AET
and EPCC values can be monitored (see
Doc ID 18315 Rev 3
frame). In Data streaming mode, the AET activity is
for possible resulting values of this internal sampling
), proximity and touch events cannot be detected (please
S
capacitor and EPCC to obtain a burst count in a
X
), the compensation capacitance value
for possible values of the EPCC capacitance.
S
capacitor and EPCC parameters to
STM8T143 processing
Section 6.2.3: Data
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