STM8T143 STMicroelectronics, STM8T143 Datasheet - Page 13

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

STM8T143
Figure 5.
1. R
The principle of charge transfer is to charge the electrode capacitance (C
power supply. When C
C
until the voltage across the sampling capacitor C
voltage (V
absence of the human body, is detected by measuring the number of transfer cycles
composing a burst (see
Throughout this document the following naming conventions apply:
●
●
●
Figure 6.
X
to an internal sampling capacitance, referred to as C
X
The charge transfer period (
subsequent transfer of the charge to C
The burst cycle duration (t
count is the number of charge transfer periods (t
The sampling period (t
must be placed as close as possible to the device.
TRIP
STM8T143 measuring circuitry
Signal monitored on C
). The change in the electrode capacitance, caused by the presence or
X
Figure
is fully charged, part of the accumulated charge is transferred from
SAMPLING
Doc ID 18315 Rev 3
BURST
6).
t
TRANSFER
) is the acquisition rate.
) is the time required to charge C
X
pin
S
) refers to the charging of C
.
S
reaches the end of acquisition reference
TRANSFER
S
. The transfer cycle is repeated
STM8T ProxSense technology
) during one t
S
X
to V
and the
X
) using a stable
TRIP
BURST
. The burst
cycle.
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