DocID026571 Rev 1

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AN4545

Device settings

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Note:

{0x1c} is a 8-bit register.

Maximum value for the Max convergence time is 63ms. Minimum value should be set to a

value of 2 or higher for range measurement to be successful.

1 code = 1 ms.

6.1.2

Inter-measurement period

The SYSRANGE__INTERMEASUREMENT_PERIOD {0x1b} register sets the Inter-

measurement period between each measurement when in continuous mode. The inter-

measurement period needs to be set to a value that is above the maximum allowable full

ranging cycle period. The following equations define the minimum inter-measurement

period to ensure correct operation:

Inter-measurement period*0.9 > Full ranging cycle = Max convergence time + 5ms.

Note:

{0x1b} is a 8-bit register.

A value of 0x00 for {0x1b} equals to a inter-measurement period 10ms. Each code will add

10ms to the inter-measurement period. e.g. inter-measurement period 50ms = 0x04.

6.1.3

Readout averaging period

The READOUT__AVERAGING_SAMPLE_PERIOD {0x10a} register sets the internal

readout averaging sample period. Increasing the sampling period decreases noise but

increases max convergence time and power consumption. Each code corresponds to

around 64.5µs additional processing time and there is a fixed 1.3ms of overhead during

readout.

Sampling period = 1.3ms + 64.5µs * READOUT__AVERAGING_SAMPLE_PERIOD

By default {0x10a} is set to 0x30 which will give a sampling period of 4.4ms.

6.2

Additional error checks

VL6180X has three additional system error checks which can be enabled to help filter out

invalid range results. See the VL6180X data sheet on how to set these error checks as well

as enabling and disabling them.