Ublox XPLR-IOT-1, User Manual

Page: 26 / 39

XPLR-IOT-1 - User guide
UBX-21035674 - R02 Platform description Page 26 of 39
C1-Public
3.5.5 Ambient light sensor
An LTR-303ALS-01 ambient light sensor from Lite-On provides a linear response over a wide dynamic
range from 0.01 Lux to 64k Lux. An interrupt output is connected to NORA-B1. This interrupt output
can be disabled by cutting jumper NC7. On the I2C bus, it is assigned address 0x29. The LTR-303ALS-
01 data sheet is available at reference
[25] .
3.5.6 Battery gauge
A BQ27421YZFR-G1A battery gauge is included with XPLR-IOT-1 to monitor the charge state of the
internal Li-Po battery. Measurements for battery capacity (mAh), state-of-charge (%), and battery
voltage (mV) are available. A low battery indicator is connected to an interrupt input of NORA-B1. On
the I2C bus, it is assigned address 0x55. The BQ27421YZFR-G1A data sheet is available at
reference
[26] .
3.5.7 Qwiic connector
To further expand the I2C bus, J5 is compatible with the Qwiic connect system defined by SparkFun
Electronics. This allows additional I2C devices operating at 3.3 V to be connected in a daisy-chain
configuration.
Table 15 shows the Qwiic pin-out. The definition of the Qwiic connect system is
available at reference [27] .
Signal J5 pin Qwiic color assignment
GND 1 Black
3.3 VDC 2 Red
SDA 3 Blue
SCL 4 Yellow
Table 15: Qwiic connector
3.6 NFC
XPLR-IOT-1 includes NFC tag capability. A flexible circuit NFC antenna, like that shown in Figure 22,
is mounted against the battery and connected to J13. The antenna functionality is compliant with
the NFC Forum definition of an NFC-A listening device. The circuit is tuned to 13.56 MHz with a bit
rate of 106 kbps. XPLR-IOT-1 can be awakened by an NFC field.
Figure 22: NFC antenna