Active Shield Or Driven Shield; Table 10. Active Shield Documentation; Figure 11. Active Shield Principle - ST STM32F0 Series Application Note

5.5.4

Active shield or driven shield

Active shield or driven shield. (this name is used in some application notes) drives the shield plane with the same
signal as the electrode.
There are several advantages using Active Shield instead of a grounded shield:
• The parasitic capacitance between the electrode and the shield no longer needs to be charged.
• Protect the touch electrodes from a noise source.
• Increase system stability and performance when a moving metal part is close to the electrode.

Table 10. Active shield documentation

Id
AN4299
AN4312
AN4316
OLT
AN5105 - Rev 1
Figure 11.
Touchkey
group X
Shield
group Y
gives a list of documents containing information about the active shield.
Table 10.
Title
Guidelines to improve conducted noise robustness
on STM32F0/F3/L0/L4 series touch sensing
applications
Guidelines for designing touch sensing
applications with surface sensors
Tuning a STMTouch-based application
STM32L4 Online Training
Active shield principle
Rs
key
IO1
IO2
IO3
IO4
Cs
key
IO1
IO2
IO3
IO4
Cs
shield
Active shield documentation
Active Shield
Driven shield
Shield adjustment
Touch sensing controller (TSC)
AN5105
Sensors
Rs
shield
Chapters
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