STMPE16M31 datasheet(59/85 Pages) STMICROELECTRONICS

59 / 85 page

STMPE16M31, STMPE24M31

Touch sensor controller

Doc ID 16174 Rev 4

59/85

13.6

Definition of data accessible through channel data register

Table 14.

Types of data accessible through the channel data register

Data name

Definition

TVR

TVR (touch variance register) is a threshold defined by system, of which, if

the sense impedance changed by a magnitude more than the associated

TVR, this channel is considered touched. The result of this comparison is

directly accessible in the TOUCH_DET register.

EVR

EVR (environmental variance register) is a threshold defined by system, of

which, if the sensed impedance changed by a magnitude less than the

associated EVR, this is considered an environmental change and the device

will calibrate the internal reference (calibrated impedance) accordingly.

Channel delay

Channel delay is used to tune the individual channel into effective

measurement range. This field is 6-bit (0-63). Each bit in this field represents

approximately 0.5 pF capacitance.

Impedance

This field is a real time reflection of impedance measured at the

corresponding channel. As capacitance is inversely proportional to

impedance, this field reduces in value when capacitance on the channel

increases.

This field is of 13-bit length. The least significant 4 bits are results of internal

processing and should not be used. The actual impedance data could be

obtained by shifting the [Impedance] 4 bits to the right.

Calibrated

Impedance

Read-only

This field contains an internal reference used by the device to decide whether

a touch has occurred. This value is adjusted regularly (calibration) by the

device automatically.

Locked impedance

Data in this field is similar to data in impedance field, except that once this

data type is chosen, the device maintains a complete set of impedance data

in this field and stop refreshing it.

This is useful for the application where it is required that all impedance data

are sampled within a very short time.

Obsolete

Product(s)

- Obsolete

Product(s)

STMPE16M31 Datenblatt(PDF) 59 Page - STMicroelectronics

STMPE16M31 Datenblatt(HTML) 59 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85

Datenblatt Download

Link URL