Telit Wireless Solutions UC864 manual Hardware Unconditional Restart

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UC864-E Hardware User Guide

1vv0300766a Rev.1 - 31/01/08

4.2.2 Hardware Unconditional Restart

To unconditionally restart UC864-E, the pad RESET# must be tied low for at least 200 milliseconds and then released.

The maximum current that can be drained from the ON# pad is 0,15 mA. A simple circuit to do it is:

RESET#

Unconditional Restart impulse

GND

NOTE: Do not use any pull up resistor on the RESET# line or any totem pole digital output. Using pull up resistor may bring to latch up problems on the UC864-E power regulator and improper functioning of the module. The line RESET# must be connected only in open collector configuration.

TIP: The unconditional hardware Restart should be always implemented on the boards and software should use it as an emergency exit procedure.

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Contents UC864 Hardware User Guide This document is relating to the following products UC864-E Hardware User GuideContents 11.2 10.310.4 11.1Disclaimer Overview Length 36.2 mm Width 30 mm Thickness 8mm Mechanical DimensionsPIN-OUT UC864-E module connectionsCmos Reserved Pin Signal Function 1 UC864-E Antenna connectorTurning on the UC864-E Hardware Commands10k Hardware shutdown Turning OFF the UC864-EHardware Unconditional Restart 10k +1.8 Power Supply Requirements Power SupplyUC864-E Hardware User Guide Electrical Design Guidelines General Design Rules1.2 + 12V input Source Power Supply Design Guidelines UC864-E Hardware User Guide Battery Source Power Supply Design Guidelines UC864-E Hardware User Guide Thermal Design Guidelines Power Supply PCB layout Guidelines Antenna Requirements AntennaAntenna Installation Guidelines Operating Range Interface levels 1.8V Cmos Logic level specificationsAbsolute Maximum Ratings -Not Functional Operating Range Interface levelsReset signal Absolute Maximum Ratings Not Functional Serial PortsSignals of the UC864-E serial port are RS232 level translation UC864-E Hardware User Guide UC864-E Hardware User Guide 5V Uart level translation UC864-E Hardware User Guide Communication ports combinations USB PortSelection Audio Section OverviewGenerality DefinitionsInput lines microphone Electrical CharacteristicsEarMT Buffers Output lines speakerNot General Purpose I/OLogic level specifications Using a Gpio Pad as Input Using a Gpio Pad as OutputUsing the Alarm Output GPIO6 Using the Buzzer Output GPIO7 LED status Device Status Indication of network service availabilityVAUX1 power output Operating Range VAUX1 power supplyRTC Bypass out Mounting UC864-E on your board USB Vbus Usbid Debug of the UC864-E in productionConformity Assessment Issues Safety Recommandations Revision Date Changes Document Change Log