i.MX 6UltraLite EVK Board Hardware User’s Guide, Rev. 1, 03/2016
Freescale Semiconductor, Inc.
17
Specifications
2. Software way to reset system using WDOG signal:
— When system assert nWDOG signal, U703 will be shutdown,and system will be power
down,and then nWDOG is released, then U703 will be power on by PMIC_ON_REQ, system
will reboot. It is important that system reset should be power down and then power on, which
will avoid boot failure caused by DVFS or DRAM (LPDDR2 if used).
2.18
Power switch (SW2001)
SW2001 is a slide switch to control the power of the i.MX 6UltraLite EVK board. The function of this
switch is listed below.
•
Sliding the switch to the ON position connects the 5V power supply to the Evaluation board main
power system.
•
Sliding the switch to OFF position immediately removes all power from the board.
2.19
Sensors
The i.MX 6UltraLite EVK board has three sensors: Accelerometer (FXLS8471Q), eCOMPASS
(MAG3110), and Gyroscope (FXAS21002CQ, unpopulated). These three sensors are connected to i.MX
6UltraLite I2C1 port.
2.19.1
Accelerometer
FXLS8471Q is a small, low-power, 3-axis, linear accelerometer in a 3 mm x 3 mm x 1 mm QFN package.
FXLS8471Q has dynamically selectable acceleration full-scale ranges of ±2 g/±4 g/±8 g and 14 bits of
resolution.
2.19.2
eCOMPASS (U1302)
MAG3110 is a small, low-power, 3-axis digital magnetometer. It works by measuring the strength of a
magnetic field, which is a combination of earth’s magnetic field and the magnetic fields of nearby objects,
including distortions. The device can be used in conjunction with a 3-axis accelerometer to produce
orientation-independent, accurate compass heading information.
2.19.3
Gyroscope (U1303)
FXAS21002CQ is a small, low-power, yaw, pitch, and roll angular rate gyroscope with 16-bit ADC
resolution. The full-scale range is adjustable from 250/s to 2000/s. It's not populated by default, so if the
developer wants to verify this feature, the chip should first be purchased and soldered.
2.20
User interface LED indicators
There are two LED status indicators located on the board. The functions of these LEDs include:
•
Main Power Supply (D2003)
— Green — DC 5V main supply (WALL_5V_DC_JACK) is normal.
— Red—WALL_5V_DC_JACK is over 5.6V.
