Information

• Configurable integration of each electrode capacitance measurement from 1 to 4096
times
• Programmable electrode oscillator and TSI Reference Oscillator for high sensitivity,
small scan time and low power functionality
• Only uses one pin per electrode implementation with no external hardware required
49.3 Overview
This section presents an overview of the TSI module. The following figure presents the
simplified TSI module block diagram.
External
Electrodes
Cap Switch
PAD0
PAD1
PAD15
Capacitance Measurement Unit
NSCN PS EXTCHRG
DELVOL
REFCHRG
TSICHnCNT
STPE
STM
Electrode
Scan Unit
EOSF
PEN [15:0]
OVRF
SMOD
LPSCNITV
Touch
Detection
Unit
TSICHnLTH
TSICHnHTH
EXTERF
OUTRGF
Touch Sensing Input (TSI) Module
Figure 49-1. Touch sensing input block diagram
49.3.1 Electrode capacitance measurement unit
The electrode capacitance measurement unit senses the capacitance of a TSI pin and
outputs a 16-bit result. This module is based in dual oscillator architecture. One oscillator
is connected to the external electrode array and oscillates according to the electrode
Overview
K10 Sub-Family Reference Manual, Rev. 6, Nov 2011
1532 Freescale Semiconductor, Inc.