Telit Wireless Solutions UC864 4 Hardware Commands

UC864-E Hardware User Guide

1vv0300766a Rev.1 - 31/01/08

4 Hardware Commands

To turn on UC864-E, the pad ON# must be tied low for at least 1 second and then released.

The maximum current that can be drained from the ON# pad is 0,1 mA.

A simple circuit to do it is:

NOTE: UC864-E turns fully on also by supplying power to the USB_VBUS pin (provided there's a battery on the

VBATT pads). Care must be taken to avoid supplying power to the USB_VBUS pin before the module turns on.

To check if the UC864-E has powered on, the hardware line PWRMON should be monitored. When PWRMON goes

high, the module has powered on.

NOTE: don't use any pull up resistor on the ON# line, it is internally pulled up. Using pull up resistor may bring to

latch up problems on the UC864-E power regulator and improper power on/off of the module. The line ON# must be

connected only in open collector configuration.

NOTE: In this document all the lines that are inverted, hence have active low signals are labeled with a name that

ends with a "#" or with a bar over the name.

NOTE: UC864-E turns fully on also by supplying power to the Charge pad (provided there's a battery on the VBATT

pads).

ON#

Power ON impulse

GND