Telit Wireless Solutions GC864 Series Installation manual

GC864 Hardware User Guide
GC864-PY, GC864-QUAD
1vv0300733 Rev. 0 - 12/06/06

GC864 Hardware User Guide
1vv0300733 Rev. 0 - 12/06/06
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Right reserved page 2 of 68
Contents
1Overview ...........................................................................................................................4
2Hardware Commands ......................................................................................................5
2.1 Turning ON the GC864 ...........................................................................................................5
2.2 Turning OFF the GC864 ........................................................................................................7
2.2.1 Hardware shutdown..........................................................................................................................7
2.3 Hardware Unconditional Reboot...........................................................................................7
3Power Supply ...................................................................................................................9
3.1 Power Supply Requirements.................................................................................................9
3.2 General Design Rules ..........................................................................................................10
3.2.1 Electrical design Guidelines........................................................................................................... 10
3.2.1.1 + 5V input Source Power Supply Design Guidelines ................................................................ 10
3.2.1.2 + 12V input Source Power Supply Design Guidelines .............................................................. 12
3.2.1.3 Battery Source Power Supply Design Guidelines ..................................................................... 13
3.2.1.4 Battery Charge control Circuitry Design Guidelines .................................................................. 13
3.2.2 Thermal Design Guidelines ........................................................................................................... 15
3.2.3 Power Supply PCB layout Guidelines ........................................................................................... 16
4Antenna...........................................................................................................................17
4.1 Antenna Requirements ........................................................................................................17
4.2 GC864 Antenna Connector..................................................................................................17
4.3 Antenna installation Guidelines..........................................................................................18
5GC864 pins allocation....................................................................................................19
NOTE: RESERVED pins must not be connected..........................................................................21
6Serial Port .......................................................................................................................22
6.1 RS232 level translation ........................................................................................................24
6.2 5V UART level translation....................................................................................................26
7Audio Section Overview ................................................................................................28
7.1 Microphone paths characteristic and requirements .........................................................30
7.2 General Design Rules ..........................................................................................................33
7.3 Other considerations. ..........................................................................................................33
7.4 Microphone Biasing .............................................................................................................34
7.4.1 Balanced Microphone biasing........................................................................................................ 34
7.4.2 Unbalanced Microphone biasing ...................................................................................................35

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7.5 Microphone buffering...........................................................................................................37
7.5.1 Buffered Balanced Mic................................................................................................................... 37
7.5.2 Buffered Unbalanced (Single Ended) Microphone . ...................................................................... 39
8OUTPUT LINES (Speaker)..............................................................................................42
8.1 Short description..................................................................................................................42
8.2 Output lines characteristics . .............................................................................................43
8.3 General Design rules............................................................................................................44
8.3.1 Noise Filtering................................................................................................................................ 44
8.4 Handset earphone design....................................................................................................45
8.5 Hands-free earphone (low power) design ..........................................................................46
8.6 Car Kit speakerphone design..............................................................................................47
9External SIM Holder .......................................................................................................48
9.1 SIM DESIGN GUIDES............................................................................................................48
10 General Purpose I/O.......................................................................................................50
10.1 Using a GPIO pad as INPUT.............................................................................................50
10.2 Using a GPIO pad as OUTPUT.........................................................................................50
10.3 Using the Alarm Output GPIO_06/ALARM......................................................................51
10.4 Using the Buzzer Output GPIO_07/BUZZER...................................................................51
11 Camera ............................................................................................................................52
11.1 Camera characteristics ....................................................................................................52
11.1.1 Camera interface connectors......................................................................................................... 52
11.1.2............................................................................................................................................................. 53
11.1.3............................................................................................................................................................. 53
11.1.4............................................................................................................................................................. 53
11.1.5 EVB for Transchip camera support ............................................................................................... 54
11.1.6 Example usage script for camera .................................................................................................. 55
12 Conformity Assessment Issues....................................................................................56
13 SAFETY RECOMMANDATIONS.....................................................................................57
14 Document Change Log ..................................................................................................58
Annex A – EVK2 schematics ...............................................................................................59
Annex B - Camera EVB schematics ....................................................................................65

GC864 Hardware User Guide
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1 Overview
The aim of this document is the description of some hardware solutions useful for developing a product with the
Telit GC864 module.
In this document all the basic functions of a mobile phone will be taken into account; for each one of them a
proper hardware solution will be suggested and eventually the wrong solutions and common errors to be
avoided will be evidenced. Obviously this document can not embrace the whole hardware solutions and
products that may be designed. The wrong solutions to be avoided shall be considered as mandatory, while the
suggested hardware configurations shall not be considered mandatory, instead the information given shall be
used as a guide and a starting point for properly developing your product with the Telit GC864 module. For
further hardware details that may not be explained in this document refer to the Telit GC864 Product Description
document where all the hardware information is reported.
NOTICE
(EN) The integration of the GC864 GSM/GPRS cellular module within user application shall be
done according to the design rules described in this manual.
(IT) L’integrazione del modulo cellulare GSM/GPRS GC864 all’interno dell’applicazione
dell’utente dovrà rispettare le indicazioni progettuali descritte in questo manuale.
(DE) Die Integration des GC864 GSM/GPRS Mobilfunk-Moduls in ein Gerät muß gemäß der in
diesem Dokument beschriebenen Konstruktionsregeln erfolgen
(SL) Integracija GSM/GPRS GC864 modula v uporabniški aplikaciji bo morala upoštevati
projektna navodila, opisana v tem priročniku.
(SP) La utilización del modulo GSM/GPRS GC864 debe ser conforme a los usos para los
cuales ha sido diseñado descritos en este manual del usuario
(FR) L'intégration du module cellulaire GC864 GSM/GPRS dans l'application de l'utilisateur
sera faite selon les règles de conception décrites dans ce manuel
(HE)
The information presented in this document is believed to be accurate and reliable. However, Telit
Communication assumes no responsibility for its use, nor any infringement of patents or other rights of third
parties which may result from its use. No license is granted by implication or otherwise under any patent rights of
Telit Communication other than for circuitry embodied in Telit products. This document is subject to change
without notice.

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2 Hardware Commands
2.1 Turning ON the GC864
To turn on the GC864 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: 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 GC864 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: The GC864 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
R1
R2
Q1

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For example:
1- Let's assume you need to drive the ON# pad with a totem pole output of a +3/5 V microcontroller
(uP_OUT1):
2- Let's assume you need to drive the ON# pad directly with an ON/OFF button:

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2.2 Turning OFF the GC864
The turning off of the device can be done in three ways:
• by software command (see GC864 Software User Guide)
• by hardware shutdown
When the device is shut down by software command or by hardware shutdown, it issues to the
network a detach request that informs the network that the device will not be reachable any more.
2.2.1 Hardware shutdown
To turn OFF the GC864 the pad ON# must be tied low for at least 1 second and then released.
The same circuitry and timing for the power on shall be used.
The device shuts down after the release of the ON# pad.
TIP: To check if the device has powered off, the hardware line PWRCTL should be monitored.
When PWRCTL goes low, the device has powered off.
2.3 Hardware Unconditional Reboot
To unconditionally Reboot the GC864, 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:
NOTE: don't use any pull up resistor on the RESET# line nor any totem pole digital output.
Using pull up resistor may bring to latch up problems on the GC864 power regulator and
improper functioning of the module. The line RESET# must be connected only in open
collector configuration.
RESET#
Unconditional Reboot
impulse
GND

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TIP: The unconditional hardware reboot should be always implemented on the boards and
software should use it as an emergency exit procedure.
For example:
1- Let's assume you need to drive the RESET# pad with a totem pole output of a +3/5 V
microcontroller (uP_OUT2):

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3 Power Supply
The power supply circuitry and board layout are a very important part in the full product design and
they strongly reflect on the product overall performances, hence read carefully the requirements and
the guidelines that will follow for a proper design.
3.1 Power Supply Requirements
The GC864 power requirements are:
• Nominal Supply Voltage: 3.8 V
• Max Supply Voltage: 4.2 V
• Supply voltage range: 3.4 V - 4.2 V
• Max Peak current consumption (impulsive): 1.9 A
• Max Average current consumption during GPRS transmission (rms): 500 mA
• Max Average current consumption during VOICE/CSD transmission (rms): 270 mA
• Average current during Power Saving: ≈4 mA
• Average current during idle (Power Saving disabled) ≈19 mA
The GSM system is made in a way that the RF transmission is not continuous, else it is packed into
bursts at a base frequency of about 216 Hz, the relative current peaks can be as high as about 2A.
Therefore the power supply has to be designed in order to withstand with these current peaks without
big voltage drops; this means that both the electrical design and the board layout must be designed for
this current flow.
If the layout of the PCB is not well designed a strong noise floor is generated on the ground and the
supply; this will reflect on all the audio paths producing an audible annoying noise at 216 Hz; if the
voltage drop during the peak current absorption is too much, then the device may even shutdown as a
consequence of the supply voltage drop.
TIP: The electrical design for the Power supply should be made ensuring it will be capable of a
peak current output of at least 2 A.

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3.2 General Design Rules
The principal guidelines for the Power Supply Design embrace three different design steps:
- the electrical design
- the thermal design.
- the PCB layout.
3.2.1 Electrical design Guidelines
The electrical design of the power supply depends strongly from the power source where this power is
drained. We will distinguish them into three categories:
• +5V input (typically PC internal regulator output)
• +12V input (typically automotive)
• Battery
3.2.1.1 + 5V input Source Power Supply Design Guidelines
• The desired output for the power supply is 3.8V, hence there's not a big difference between the
input source and the desired output and a linear regulator can be used. A switching power supply
will not be suited because of the low drop out requirements.
• When using a linear regulator, a proper heat sink shall be provided in order to dissipate the power
generated.
• A Bypass low ESR capacitor of adequate capacity must be provided in order to cut the current
absorption peaks close to the GC864, a 100μF tantalum capacitor is usually suited.
• Make sure the low ESR capacitor on the power supply output (usually a tantalum one) is rated at
least 10V.
• A protection diode should be inserted close to the power input, in order to save the GC864 from
power polarity inversion.

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An example of linear regulator with 5V input is:

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3.2.1.2 + 12V input Source Power Supply Design Guidelines
• The desired output for the power supply is 3.8V, hence due to the big difference between the input
source and the desired output, a linear regulator is not suited and shall not be used. A switching
power supply will be preferable because of its better efficiency especially with the 2A peak current
load represented by the GC864.
• When using a switching regulator, a 500kHz or more switching frequency regulator is preferable
because of its smaller inductor size and its faster transient response. This allows the regulator to
respond quickly to the current peaks absorption.
• For car PB battery the input voltage can rise up to 15,8V and this should be kept in mind when
choosing components: all components in the power supply must withstand this voltage.
• A Bypass low ESR capacitor of adequate capacity must be provided in order to cut the current
absorption peaks, a 100μF tantalum capacitor is usually suited.
• Make sure the low ESR capacitor on the power supply output (usually a tantalum one) is rated at
least 10V.
• For Car applications a spike protection diode should be inserted close to the power input, in order
to clean the supply from spikes.
• A protection diode should be inserted close to the power input, in order to save the GC864 from
power polarity inversion. This can be the same diode as for spike protection.
An example of switching regulator with 12V input is:

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3.2.1.3 Battery Source Power Supply Design Guidelines
• The desired nominal output for the power supply is 3.8V and the maximum voltage allowed is
4.2V, hence a single 3.7V Li-Ion cell battery type is suited for supplying the power to the Telit
GC864 module.
The three cells Ni/Cd or Ni/MH 3,6 V Nom. battery types or 4V PB types MUST NOT BE USED
DIRECTLY since their maximum voltage can rise over the absolute maximum voltage for the
GC864 and damage it.
NOTE: DON'T USE any Ni-Cd, Ni-MH, and Pb battery types directly connected with GC864.
Their use can lead to overvoltage on the GC864 and damage it. USE ONLY Li-Ion battery types.
• A Bypass low ESR capacitor of adequate capacity must be provided in order to cut the current
absorption peaks, a 100μF tantalum capacitor is usually suited.
• Make sure the low ESR capacitor (usually a tantalum one) is rated at least 10V.
• A protection diode should be inserted close to the power input, in order to save the GC864 from
power polarity inversion. Otherwise the battery connector should be done in a way to avoid polarity
inversions when connecting the battery.
• The battery capacity must be at least 500mAh in order to withstand the current peaks of 2A; the
suggested capacity is from 500mAh to 1000mAh.
3.2.1.4 Battery Charge control Circuitry Design Guidelines
The charging process for Li-Ion Batteries can be divided into 4 phases:
• Qualification and trickle charging
• Fast charge 1 - constant current
• Final charge - constant voltage or pulsed charging
• Maintenance charge
The qualification process consists in a battery voltage measure, indicating roughly its charge status. If
the battery is deeply discharged, that means its voltage is lower than the trickle charging threshold,
then the charge must start slowly possibly with a current limited pre-charging process where the
current is kept very low with respect to the fast charge value: the trickle charging.
During the trickle charging the voltage across the battery terminals rises; when it reaches the fast
charge threshold level the charging process goes into fast charge phase.
During the fast charge phase the process proceeds with a current limited charging; this current limit
depends on the required time for the complete charge and from the battery pack capacity. During this
phase the voltage across the battery terminals still raises but at a lower rate.
Once the battery voltage reaches its maximum voltage then the process goes into its third state: Final
charging. The voltage measure to change the process status into final charge is very important. It
must be ensured that the maximum battery voltage is never exceeded, otherwise the battery may be
damaged and even explode. Moreover for the constant voltage final chargers, the constant voltage
phase (final charge) must not start before the battery voltage has reached its maximum value,
otherwise the battery capacity will be highly reduced.
The final charge can be of two different types: constant voltage or pulsed. GC864 uses constant
voltage.
The constant voltage charge proceeds with a fixed voltage regulator (very accurately set to the
maximum battery voltage) and hence the current will decrease while the battery is becoming charged.

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When the charging current falls below a certain fraction of the fast charge current value, then the
battery is considered fully charged, the final charge stops and eventually starts the maintenance.
The pulsed charge process has no voltage regulation, instead the charge continues with pulses.
Usually the pulse charge works in the following manner: the charge is stopped for some time, let's say
few hundreds of ms, then the battery voltage will be measured and when it drops below its maximum
value a fixed time length charging pulse is issued. As the battery approaches its full charge the off
time will become longer, hence the duty-cycle of the pulses will decrease. The battery is considered
fully charged when the pulse duty-cycle is less than a threshold value, typically 10%, the pulse charge
stops and eventually the maintenance starts.
The last phase is not properly a charging phase, since the battery at this point is fully charged and the
process may stop after the final charge. The maintenance charge provides an additional charging
process to compensate for the charge leak typical of a Li-Ion battery. It is done by issuing pulses with
a fixed time length, again few hundreds of ms, and a duty-cycle around 5% or less.
This last phase is not implemented in the GC864 internal charging algorithm, so that the battery once
charged is left discharging down to a certain threshold so that it is cycled from full charge to slight
discharge even if the battery charger is always inserted. This guarantees that anyway the remaining
charge in the battery is a good percentage and that the battery is not damaged by keeping it always
fully charged (Li-Ion rechargeable battery usually deteriorate when kept fully charged).
Last but not least, in some applications it is highly desired that the charging process restarts when the
battery is discharged and its voltage drops below a certain threshold, GC864 internal charger does it.
As you can see, the charging process is not a trivial task to be done; moreover all these operations
should start only if battery temperature is inside a charging range, usually 5°C - 45°C.
The GC864 measures the temperature of its internal component, in order to satisfy this last
requirement, it's not exactly the same as the battery temperature but in common application the two
temperature should not differ too much and the charging temperature range should be guaranteed.
NOTE: For all the threshold voltages, inside the GC864 all threshold are fixed in order to
maximize Li-Ion battery performances and do not need to be changed.
NOTE: In this application the battery charger input current must be limited to less than 400mA.
This can be done by using a current limited wall adapter as the power source.

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3.2.2 Thermal Design Guidelines
The thermal design for the power supply heat sink should be done with the following specifications:
• Average current consumption during transmission @PWR level max (rms): 500mA
• Average current consumption during transmission @ PWR level min (rms): 100mA
• Average current during Power Saving: 4mA
• Average current during idle (Power Saving disabled) 19mA
NOTE: The average consumption during transmissions depends on the power level at which
the device is requested to transmit by the network. The average current consumption hence
varies significantly.
TIP: The thermal design for the Power supply should be made keeping a average consumption
at the max transmitting level during calls of 500mA rms.
Considering the very low current during idle, especially if Power Saving function is enabled, it is
possible to consider from the thermal point of view that the device absorbs current significantly only
during calls.
If we assume that the device stays into transmission for short periods of time (let's say few minutes)
and then remains for a quite long time in idle (let's say one hour), then the power supply has always
the time to cool down between the calls and the heat sink could be smaller than the calculated one for
500mA maximum RMS current, or even could be the simple chip package (no heat sink).
Moreover in the average network conditions the device is requested to transmit at a lower power level
than the maximum and hence the current consumption will be less than the 500mA, being usually
around 150mA.
For these reasons the thermal design is rarely a concern and the simple ground plane where the
power supply chip is placed can be enough to ensure a good thermal condition and avoid overheating.
For the heat generated by the GC864, you can consider it to be during transmission 1W max during
CSD/VOICE calls and 2W max during class10 GPRS upload.
This generated heat will be mostly conducted to the ground plane under the GC864, you must ensure
that your application can dissipate it.

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3.2.3 Power Supply PCB layout Guidelines
As seen on the electrical design guidelines the power supply shall have a low ESR capacitor on the
output to cut the current peaks and a protection diode on the input to protect the supply from spikes
and polarity inversion. The placement of these components is crucial for the correct working of the
circuitry. A misplaced component can be useless or can even decrease the power supply
performances.
• The Bypass low ESR capacitor must be placed close to the Telit GC864 power input pads or in the
case the power supply is a switching type it can be placed close to the inductor to cut the ripple
provided the PCB trace from the capacitor to the GC864 is wide enough to ensure a dropless
connection even during the 2A current peaks.
• The protection diode must be placed close to the input connector where the power source is
drained.
• The PCB traces from the input connector to the power regulator IC must be wide enough to ensure
no voltage drops occur when the 2A current peaks are absorbed. Note that this is not made in
order to save power loss but especially to avoid the voltage drops on the power line at the current
peaks frequency of 216 Hz that will reflect on all the components connected to that supply,
introducing the noise floor at the burst base frequency. For this reason while a voltage drop of 300-
400 mV may be acceptable from the power loss point of view, the same voltage drop may not be
acceptable from the noise point of view. If your application doesn't have audio interface but only
uses the data feature of the Telit GC864, then this noise is not so disturbing and power supply
layout design can be more forgiving.
• The PCB traces to the GC864 and the Bypass capacitor must be wide enough to ensure no
significant voltage drops occur when the 2A current peaks are absorbed. This is for the same
reason as previous point. Try to keep this trace as short as possible.
• The PCB traces connecting the Switching output to the inductor and the switching diode must be
kept as short as possible by placing the inductor and the diode very close to the power switching
IC (only for switching power supply). This is done in order to reduce the radiated field (noise) at the
switching frequency (100-500 kHz usually).
• The use of a good common ground plane is suggested.
• The placement of the power supply on the board should be done in such a way to guarantee that
the high current return paths in the ground plane are not overlapped to any noise sensitive circuitry
as the microphone amplifier/buffer or earphone amplifier.
• The power supply input cables should be kept separate from noise sensitive lines such as
microphone/earphone cables.

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4 Antenna
The antenna connection and board layout design are the most important part in the full product design
and they strongly reflect on the product overall performances, hence read carefully and follow the
requirements and the guidelines for a proper design.
4.1 Antenna Requirements
As suggested on the Product Description the antenna for a Telit GC864 device shall fulfill the following
requirements:
ANTENNA REQUIREMENTS
Frequency range Standard Dual Band GSM/DCS frequency
range or
Standard Tri Band GSM/DCS/PCS
frequency range if used for all three bands
Bandwidth 136 MHz in GSM 850 and 900 & 170 MHz in
DCS & 140 MHz PCS band
Gain Gain < 3dBi
Impedance 50 ohm
Input power > 2 W peak power
VSWR absolute
max
<= 10:1
VSWR
recommended
<= 2:1
4.2 GC864 Antenna Connector
The GC864 module is equipped with a 50 Ohm RF connector from Murata,
GSC type P/N MM9329-2700B.
The counterpart suitable is Murata MXTK92 Type or MXTK88 Type.
Moreover, the GC864 has the antenna pads on the backside of the PCB. This allows the manual
soldering of the coaxial cable directly on the back side of the PCB. However, the soldering is not an
advisable solution for a reliable connection of the antenna.

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4.3 Antenna installation Guidelines
• Install the antenna in a place covered by the GSM signal.
• The Antenna must be installed to provide a separation distance of at least 20 cm from all persons
and must not be co-located or operating in conjunction with any other antenna or transmitter;
• Antenna shall not be installed inside metal cases
• Antenna shall be installed also according Antenna manufacturer instructions.

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5 GC864 pins allocation
The GC864 uses an 80 pin Molex p.n. 53949-0878 male connector for the connections with the external
applications. This connector matches the 54150-0878 model.
Pin Signal I/O Function Internal
Pull up
Type
Power Supply
1 VBATT - Main power supply Power
2 VBATT - Main power supply Power
3 VBATT - Main power supply Power
4 VBATT - Main power supply Power
5 GND - Ground Power
6 GND - Ground Power
7 GND - Ground Power
Audio
8 AXE I Handsfree switching 100K
Ω CMOS 2.8V
9 EAR_HF+ AO Handsfree ear output, phase + Audio
10 EAR_HF- AO Handsfree ear output, phase - Audio
11 EAR_MT+ AO Handset earphone signal output, phase + Audio
12 EAR_MT- AO Handset earphone signal output, phase - Audio
13 MIC_HF+ AI Handsfree microphone input; phase +, nominal level 3mVrms Audio
14 MIC_HF- AI Handsfree microphone input; phase -, nominal level 3mVrms Audio
15 MIC_MT+ AI Handset microphone signal input; phase+, nominal level 50mVrms Audio
16 MIC_MT- AI Handset microphone signal input; phase-, nominal level 50mVrms Audio
SIM Card Interface
18 SIMVCC - External SIM signal – Power supply for the SIM 1.8/3V
19 SIMRST O External SIM signal – Reset 1.8/3V
20 SIMIO I/O External SIM signal - Data I/O 1.8/3V
21 SIMIN I External SIM signal - Presence (active low) 47K
Ω 1.8/3V
22 SIMCLK O External SIM signal – Clock 1.8/3V
Trace
23 RX_TRACE I RX Data for debug monitor CMOS 2.8V
24 TX_TRACE O TX Data for debug monitor CMOS 2.8V
Prog. / Data + Hw Flow Control
25 C103/TXD I Serial data input (TXD) from DTE CMOS 2.8V
26 C104/RXD O Serial data output to DTE CMOS 2.8V

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Pin Signal I/O Function Internal
Pull up
Type
27 C107/DSR O Output for Data set ready signal (DSR) to DTE CMOS 2.8V
28 C106/CTS O Output for Clear to send signal (CTS) to DTE CMOS 2.8V
29 C108/DTR I Input for Data terminal ready signal (DTR) from DTE CMOS 2.8V
30 C125/RING O Output for Ring indicator signal (RI) to DTE CMOS 2.8V
31 C105/RTS I Input for Request to send signal (RTS) from DTE CMOS 2.8V
32 C109/DCD O Output for Data carrier detect signal (DCD) to DTE CMOS 2.8V
IIC
35 CAM_SCL /
IIC_SCL
I/O Camera IIC interface / Configurable GPIO CMOS 2.8V
36 CAM_SDA /
IIC_SDA
I/O Camera IIC interface / Configurable GPIO CMOS 2.8V
DAC and ADC
37 ADC_IN1 AI Analog/Digital converter input A/D
38 ADC_IN2 AI Analog/Digital converter input A/D
39 ADC_IN3 AI Analog/Digital converter input A/D
40 DAC_OUT AO Digital/Analog converter output D/A
Miscellaneous Functions
44 MON1_CAM I/O MON1 / Camera interface CMOS 2.8V
45 STAT_LED O Status indicator led CMOS 1.8V
46 GND - Ground Ground
49 PWRMON I Power ON Monitor CMOS 2.8V
50 VAUX1 - Power output for external accessories -
51 CHARGE AI Charger input (*) Power
52 CHARGE AI Charger input (*) Power
53 ON/OFF* I Input command for switching power ON or OFF (toggle command).
The pulse to be sent to the GC864 must be equal or greater than 1
second.
47K
Ω Pull up to VBATT
54 RESET* I Reset input
55 VRTC AO VRTC Backup capacitor Power
Telit GPIO
56 TGPIO_19 I/O Telit GPIO19 Configurable GPIO CMOS 2.8V
57 TGPIO_11 I/O Telit GPIO11 Configurable GPIO CMOS 2.8V
58 TGPIO_20 I/O Telit GPIO20 Configurable GPIO CMOS 2.8V
59 TGPIO_04 I/O Telit GPIO4 Configurable GPIO CMOS 2.8V
60 TGPIO_14 I/O Telit GPIO14 Configurable GPIO CMOS 2.8V
61 TGPIO_15 I/O Telit GPIO15 GPIO pin CMOS 2.8V
62 TGPIO_12 I/O Telit GPIO12 Configurable GPIO CMOS 2.8V
63 TGPIO_10 I/O Telit GPIO10 I/O pin CMOS 2.8V
64 TGPIO_22 I/O Telit GPIO22 Configurable GPIO CMOS 1.8V
65 TGPIO_18 I/O Telit GPIO18 I/O pin CMOS 2.8V
66 TGPIO_03 I/O Telit GPIO3 Configurable GPIO CMOS 2.8V