Data Sheet

DocID029104 Rev 2 15/40

VL53L0X Functional description

2.6.1 Initialization and load calibration data phase

Initialization and calibration phase is performed before the first ranging or after a device

reset, see

Figure 9.

The user may then have to repeat the temperature calibration phase in a periodic way,

depending on the use case.

For more details on the calibration functions please refer to the VL53L0X API User Manual.

2.6.2 Ranging phase

The ranging phase consists of a range setup then range measurement.

During the ranging operation, several VCSEL infrared pulses are emitted, then reflected

back by the target object, and detected by the receiving array. The photo detector used

inside VL53L0X is using advanced ultra-fast SPAD technology (Single Photon Avalanche

Diodes), protected by several patents.

The typical timing budget for a range is 33ms (init/ranging/housekeeping), see Figure 12,

with the actual range measurement taking 23ms, see Figure 9. The minimum range

measurement period is 8ms.

2.6.3 Digital housekeeping

Digital processing (housekeeping) is the last operation inside the ranging sequence that

computes, validates or rejects a ranging measurement. Part of this processing is performed

internally while the other part is executed on the Host by the API.

At the end of the digital processing, the ranging distance is computed by VL53L0X itself. If

the distance could not be measured (weak signal, no target…), a corresponding error code

is provided.

The following functions are performed on the device itself:

• Signal value check (weak signal)

• Offset correction

• Cross-talk correction (in case of cover glass)

• Final ranging value computation

While the API performs the following:

• Return Ignore Threshold RIT check (Signal check versus cross talk)

• Sigma check (accuracy condition)

• Final ranging state computation

If the user wants to enhance the ranging accuracy, some extra processing (not part of the

API) can be carried out by the host, for example, rolling average, hysteresis or any kind of

filtering.