Changes

AXELULite AXEL ULite adapter is a board that DAVE Embedded Systems has made available to make initial development on AXELULiteAXEL ULite-based systems easier.

In principle it can be used with any carrier board designed to host 3.3V-powered AXELULite AXEL ULite SOM. These SOMs have the ordering code in one of the [[Power_Power (AXELULiteAXEL ULite)|following forms]]:

AXELULite AXEL ULite adapter has to be interposed between the carrier board and AXELULite AXEL ULite SOM as shown by the following picture.

As described [[Boot_process_and_bootstrap_configuration_(AXELULiteAXEL ULite)|here]], ''GPIO ovverride'' mode is extremely helpful when it comes to select different boot configuration options. AXELULite AXEL ULite adapter provides a bank of switches that allows to change both <code>BOOT_MODE</code> and <code>LCD1_DATAx</code> signals affecting boot configurations. When the switch is in ON position, "0" logic level is selected.

From the point of view of power status, AXELULite AXEL ULite SOM can operate in [[Power consumption (AXELULiteAXEL ULite)|different modes]]. When operating in SNVS mode, power comnsumption may be relatively high if:

AXELULite AXEL ULite adapter integrates such an RTC (ST M41T83) that allows the user to compare this solution with respect to the one based on iMX6UL native RTC.

This circuit is based on [http://www.ti.com/product/INA226 Texas Instruments INA226] and it is used to measure power consumption of AXELULite AXEL ULite SOM. This device is accessible via I2C bus either by iMX6UL itself [1] or by an external host connected to test points TP3 and TP4.

[1] Clearly this is not possible for all of the [[Power_consumption_Power consumption (AXELULiteAXEL ULite)|iMX6UL operating modes]].

AXELULite AXEL ULite SOM is powered by VIN_3V3 that, in turn, originates at carrier board level. VIN_3V3 is connected to the net VIN_SOM through a shunt resistor (R12) that is used by power measurement circuit.

The rest of the circuitry is powered by 3.3V rail that is turned on via U70 switch. This switch - enabled by the SOM_PGOOD signal - is used to implement proper power up sequence, as described [[Power_Power (AXELULiteAXEL ULite)|here]].

A tiny microcontroller (U68) is used to implement a voltage monitoring circuit to verify that the difference between native AXELULite AXEL ULite I/O voltage (SOM_3V3_IO) and 3.3V does not exceed 300mV, as per [[Power_Power (AXELULiteAXEL ULite)#Introduction|design requirement]]. In case this condition is not met, the microcontroller triggers a full power up cycle via PMIC_PWRON.