Data Sheet

DocID031478 Rev 1 5/28
UM2356 Ranging API function descriptions
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2 Ranging API function descriptions
This section give a functional description of the ranging and describes the API call flow that
should be followed to perform a ranging measurement using the VL53L1X.
2.1 Autonomous ranging description
The sensor performs the ranging continuously and autonomously with a programmable
inter-measurement period.
Ranging is done without involvement from the host which allows the host to be in a low-
power state. The host is only woken up upon measurement interrupts when a ranging is
available.
It is possible to set a threshold of distance and/or signal detection criteria, then an interrupt
is raised when the criteria is met.
2.2 Timing considerations
The timing budget is defined as the programmed time needed by the sensor to perform and
report ranging measurement data. During this time, the VCSEL is pulsed. An interrupt is
raised or the date ready register is updated at the end of the timing budget.
The inter-measurement period is defined as the programmed time between two consecutive
measurements.
Figure 3 shows the timing budget and inter-measurement period.
The host can change the default timing budget and inter-measurement period by using a
dedicated driver function described in
Section 2.5.2: Timing budget and inter-measurement
period.
The host can decide to change the timing budget to improve ranging accuracy or maximum
distance limits.
Figure 3. VL53L1X autonomous ranging sequence and timings
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