VL6180 datasheet(28/73 Pages) STMICROELECTRONICS

28 / 73 page

Functional description

VL6180

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DocID024986 Rev 14

2.15

Other system considerations

This section describes part-to-part range offset and system cross-talk. In addition, a

procedure for cross-talk calibration is given.

2.15.1

Part-to-part range offset

The VL6180 is factory calibrated to produce an absolute linear range output as shown in

Figure 18. The part-to-part range offset is calibrated during manufacture and stored in NVM.

Use VL6180x_GetOffsetCalibrationData() to read offset from NVM (after

VL6180x_InitData()). The API always returns the range with the part-to-part offset already

applied.

Figure 18. Part-to-part range offset

2.15.2

Cross-talk

Cross-talk is defined as the signal return from the cover glass. The magnitude of the cross-

talk depends on the type of glass, air gap and filter material. Cross-talk results in a range

error (see Figure 19) which is proportional to the ratio of the cross-talk to the signal return

from the target. The true range is recovered by applying automatic cross-talk compensation.

Figure 19. Cross-talk compensation

Cross-talk compensation is enabled by using VL6180x_SetXTalkCompensationRate(). A

cross-talk calibration procedure is described in Section 2.15.4.

VL6180 Datasheet(PDF) 28 Page - STMicroelectronics