QST102 STMicroelectronics, QST102 Datasheet - Page 11

• Manufacturer Part Number: QST102
• Description: Capacitive Touch Sensor Device 2 Keys With Individual Key State Outputs
• Manufacturer: STMicroelectronics

QST102
4.4
4.5
4.6
Adjacent key suppression (AKS™)
The adjacent key suppression (AKS™) function is enabled using the AKS option resistor
(pin KOUT1/AKS) as described in
Table 3.
Max on-duration
The Max On-Duration time is set to 30 seconds. This means that a continuous “touched”
detection for 30 seconds on a key triggers a recalibration. When such an event occurs, only
the “stuck” key is recalibrated.
Serial validation interface (SVI)
The serial validation interface (SVI) acts as an SPI master device. It provides access to the
following internal device information:
●
●
This data access facilitates system tuning an can be used as a debug interface.
To enter SVI mode, before power-up connect resistor R
input 1 pins as shown in
resistor R
After this 10-second delay, the device operates normally with SVI data and clock signals
being output on pins KOUT1 and KOUT2, respectively.
Please refer to RM0014: QST serial validation interface reference manual for more
information about the SVI operating mode.
device identifier string sent once after the Reset phase
internal system parameters sent after each acquisition
–
–
–
KOUT1/AKS
V
V
key states
key references
key signals
SVI
DD
SS
AKS truth table
in order to not modify Key 1 electrode calibration and operation.
Disabled
Global locking AKS on all available keys
Figure
5. Then, within 10 seconds following power-up disconnect
Table
3.
Description
SVI
between SVI input 0 and SVI
Device operating mode
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