VL53L5CX Offset Calibration

[MFabb.1]

Hi,

I noticed that an offset calibration function is missing in the API of the VL53L5CX (like seen before on VL53L1CX). Only the xtalk calibration is available.

Is this because all the VL53L5CXs are individually factory offset-calibrated?

My assumption is also based on the following section of the vl53l5cx_init() function:

	/* Get offset NVM data and store them into the offset buffer */
	status |= WrMulti(&(p_dev->platform), 0x2fd8,
		(uint8_t*)VL53L5CX_GET_NVM_CMD, sizeof(VL53L5CX_GET_NVM_CMD));
	status |= _vl53l5cx_poll_for_answer(p_dev, 4, 0,
		VL53L5CX_UI_CMD_STATUS, 0xff, 2);
	status |= RdMulti(&(p_dev->platform), VL53L5CX_UI_CMD_START,
		p_dev->temp_buffer, VL53L5CX_NVM_DATA_SIZE);
	(void)memcpy(p_dev->offset_data, p_dev->temp_buffer,
		VL53L5CX_OFFSET_BUFFER_SIZE);
	status |= _vl53l5cx_send_offset_data(p_dev, VL53L5CX_RESOLUTION_4X4);

where offset data are readed from NVM and loaded into the offset buffer.

Offset calibration on host side must be implemented when VL53L5CX is integrated behind a clear plastic glass with low crosstalk component?

Thank you

[John E KVAM · Accepted solution]

Actually we do an offset calibration on all our parts. But it was seen that the offset changed on a lot of the single-zone parts after the parts were soldered onto boards. The solution was to recommend the offset calibration on the single zone parts.

But the multizone parts work differently. The factory calibration is holding up even after several reflow operations.

We are very pleased to be able to delete the offset calibration requirement.

And thanks for asking.

• john

[MFabb.1]

Thank you John!

This should be reported somewhere in the datasheet or in a specific application note.