User's Manual

UE866 HARDWARE USER GUIDE 1vv0301157 Rev.7 • 2015-04-17 24 of 68

4.4 RTC Bypass out

The VRTC pin brings out the Real Time Clock supply, which is separate from the rest of the digital

part, allowing having only RTC going on when all the other parts of the device are off.

To this power output a backup capacitor can be added in order to increase the RTC autonomy during

power off of the battery. NO Devices must be powered from this pin.

In order to keep the RTC active when VBATT is not supplied it is possible to back up the RTC section

connecting a backup circuit to the related VRTC signal (pad F5 on module’s Pinout).

For additional details on the Backup solutions please refer to the related application note (RTC

Backup Application Note)

4.5 VAUX Power Output

A regulated power supply output is provided in order to supply small devices from the module. The

signal is present on Pad G6 and it is in common with the PWRMON (module powered ON indication)

function.

This output is always active when the module is powered ON.

The operating range characteristics of the supply are:

Item

Min

Typical

Max

Output voltage

1.77V

1.80V

1.83V

Output current

60mA

Output bypass

capacitor

(inside the module)

22uF

NOTE:

The Output Current MUST never be exceeded; care must be taken when

designing the application section to avoid having an excessive current

consumption.

If the Current is exceeding the limits it could cause a Power Off of the module.