stmpe16m31 STMicroelectronics, stmpe16m31 Datasheet - Page 60

• Manufacturer Part Number: stmpe16m31
• Description: S-touch? 16/24-channel Touchkey Controller With Pwm And Ratio Engines
• Manufacturer: STMicroelectronics

Touch sensor controller
13.7
60/85
Ratiometric engine
The STMPE16M31/24M31 support ratiometric slider/wheel implementation where a very
high number of steps could be obtained from relatively few physical sensing channels. The
high number of steps is derived from the ratio of capacitance sensed between neighboring
channels.
To use the ratio engine, the system must:
Table 15.
Figure 17. Configuration of ratio
Address
0x80
0x81
0x82
0x83
0x84
0x87
–
–
–
–
–
–
Define a range of channels (must be continuous) between 3-8 channels to be
Used as slider/wheel input
Select slider/wheel configuration
Select noise filter setting
Enable ratio engine
After each set of data access, the RE bit in interrupt status register must be
cleared.
Ratiometric engine registers
RATIO_ENG1_DATA
RATIO_ENG2_DATA
RATIO_ENG1_CFG
RATIO_ENG2_CFG
RATIO_ENG_SET
RATIO_ENG_STA
Register name
Doc ID 16174 Rev 3
Reset value
0x000000
0x000000
0x00
0x00
0x00
0x00
R/W
RW
RW
RW
R
R
R
General setup of ratio engine
Configuration of ratio engine 1
Configuration of ratio engine 2
Status of ratio engine
Output data of ratio engine 1
Output data of ratio engine 2
STMPE16M31, STMPE24M31
Description