stmpe16m31 STMicroelectronics, stmpe16m31 Datasheet - Page 8

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

Pin assignment
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Figure 4.
Table 3.
1. For small PCBs, it is possible to operate the device with CRef left unconnected. However, without a small
highest and lowest channel
capacitance at this pin, the capacitive sensing operation tends to be noisier. It is recommended that a
capacitor of 10 pF to be connected to this pin.
(Difference between
> 30 pF, < 60 pF
capacitance)
Cmax-Cmin
< 30 pF
<3 0 pF
> 60 pF
Sample application - notebook multimedia bar
Limitations on intrinsic capacitance on PCB / flexi PCB
Doc ID 16174 Rev 3
> 30 pF, < 60 pF
> 30 pF, < 60 pF
< 30 pF
> 60 pF
Cmax
Channel matching capacitance of up
STMPE16M31, STMPE24M31
Cref of up to 30 pF required
Cref of up to 30 pF required
PCB optimization required
Matching capacitors
to 25 pF required
Not required
(1)