Panasonic EB-GD90 Quick start guide

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Order Number: MCUK990801G8
Issue 1
Revision 0
Technical Guide
GD90 Personal Cellular Telephone
Handheld Portable
EB-GD90
Specification
Unless stated these specifications are with Battery Pack (EB-BSD90) fitted.
Battery life figures are dependent on network conditions.
900 MHz 1800 MHz
Frequency range Tx: 890 - 915 MHz
Rx: 935 - 960 MHz
Tx: 1710 - 1785 MHz
Rx: 1805 - 1880 MHz
Tx/Rx frequency separation 45 MHz 95 MHz
RF channel bandwidth 200 kHz
Number of RF channels 124 374
Speech coding Full rate/Half rate/Enhanced
Full rate
Full rate/Half rate
Operating temperature -10°C to +55°C
Type Class 4 Handheld Class 1 Handheld
RF Output Power 2 W maximum 1 W maximum
Modulation GMSK (BT = 0.3)
Connection 8 ch/TDMA
Voice digitizing 13 kbps RPE-LTP / 13 kps ACLEP / 5.6 kps CELP / VSLEP
Transmission speed 270.3 kbps
Diversity Frequency hopping
Signal Reception Double superheterodyne
Intermediate Frequency 282MHz and 45MHz
Antenna Terminal Impedance 50 Ω
Antenna VSWR <2.1 : 1
Dimensions Height: 118 mm
Width: 42 mm
Depth: 16.5 mm
Volume 84.5 cc
Weight 88 g
Display Graphical chip on glass liquid crystal, Alphanumeric 16 x 3
characters, 5 icons and 6 x 1 characters
Illumination Green:
4 LEDs for the LCD
8 LEDs for the keyboards
1 LED Incoming call
Red:
1 LED Charging indicator
Keypad 17 keys, Navigation key
SIM Plug-in type only
External DC Supply Voltage 3.6 V
Battery 3.6 V
Standby Battery Life
DRX 9
95 hrs maximum
Conversation Battery Life
PL 7, DTX 50%
200 minutes
WARNING
This service information is designed for experienced repair technicians only and is not designed for use by the general public. It does not contain warnings or
cautions to advise non-technical individuals of potential dangers in attempting to service a product.
Products powered by electricity should be serviced or repaired only by experienced professional technicians. Any attempt to service or repair the product or
products dealt with in this service manual by anyone else could result in serious injury or death.

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Issue 1 – ii – MCUK990801G8
Revision 0 Technical Guide
This Technical Guide is copyright and issued on the strict understanding that it is not to be reproduced, copied, or disclosed to
any third party, either in whole or part, without the prior written consent of Matsushita Communication Industrial UK Ltd.
Every care has been taken to ensure that the contents of this publication give an accurate representation of the equipment.
However, Matsushita Communication Industrial UK Ltd. accepts no responsibility for inaccuracies which may occur and
reserves the right to make changes to the specification or design without prior notice.
The information contained in this manual and all rights in any designs disclosed therein, are and remain the exclusive property
of Matsushita Communication Industrial UK Ltd.
Other patents applying to material contained in this publication:
BULL CP8 PATENTS
Comments or correspondence concerning this manual should be addressed to:
Customer Support Department,
Matsushita Communication Industrial UK Ltd.,
Colthrop,Thatcham,
Berkshire. RG19 4ZD.
ENGLAND
© 1999 Matsushita Communication Industrial UK Ltd.

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MCUK990801G8 Section Issue 1
Technical Guide – iii – Revision 0
CONTENTS
1 INTRODUCTION
1.1 Purpose of this Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Structure of the Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2 INTERFACES AND TEST POINTS
2.1 Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3 RF OVERVIEW
3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.2 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.3 RF & Accessory Connector . . . . . . . . . . . . . . . . . . . . . . 10
4 TRANSMITTER
4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.2 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . 12
5 RECEIVER
5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.2 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . 16
6 BASEBAND OVERVIEW
6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
6.2 Functional Description of the PCB . . . . . . . . . . . . . . . . 19
7 GEMINI
7.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
7.2 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . 25
8 VEGA
8.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
8.2 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . 29
9 POWER SUPPLIES
9.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
9.2 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
9.3 Power-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
9.4 Power-down . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
9.5 Power Management . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

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INTRODUCTION
MCUK990801G8 Section 1 Issue 1
Technical Guide – 1 – Revision 0
1 INTRODUCTION
1.1 Purpose of this Guide
This guide contains technical information for the Panasonic GD90 personal cellular telephone system operating on the GSM
network. Procedures for installing, operating and servicing (e.g. disassembly and testing) the telephone system are provided
in the associated Service Manual.
1.2 Structure of the Guide
The guide is structured to provide service-engineering personnel with the following technical information on the GSM mobile
telephone:
1. Interface details and relevant test points.
2. Functional description of each section of the mobile telephone.
3. Detailed description of each section of the mobile telephone.

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INTERFACES AND TEST POINTS
MCUK990801G8 Section 2 Issue A
Technical Guide – 9 – Revision 0
2 INTERFACES AND TEST POINTS
2.1 Interfaces
2.1.1 Main and Keypad PCBs
The interface between Main and Keypad PCBs is made via a 34-way connector as follows:
Figure 2.1: GD90 Interboard Connector
No. Signal Name MAIN <=> KEYPAD Function Connection
1 GROUND -
2 D28V - Power Source for LCD Module
3 KEYBKLT ==> Key Backlight Power Source Charge IC pin 16
4 LCD_GRN ==> LCD Green Backlight Power Charge IC pin 18
5 LCD_RED ==> LCD Red Backlight Power Charge IC pin 17
6 A(1) ==> MPU Address bus (1) GEMINI pin 25
7 RnW ==> MPU Read/nWrite signal GEMINI pin 20
8 KBC(4) ==> Key Column 4 signal for Key scan GEMINI pin 128
9 KBC(3) ==> Key Column 3 signal for Key scan GEMINI pin 129
10 KBC(2) ==> Key Column 2 signal for Key scan GEMINI pin 130
11 KBC(0) ==> Key Column 0 signal for Key scan GEMINI pin 132
12 KBC(1) ==> Key Column 1signal for Key scan GEMINI pin 133
13 D(4) <==> MPU Data bus (4)
14 D(3) <==> MPU Data bus (3)
15 D(2) <==> MPU Data bus (2)
16 D(1) <==> MPU Data bus (1)
17 D(0) <==> MPU Data bus (0)
18 GROUND - l
19 D28V - Power Source for LCD Module
20 nPOWKEY <== Power Key sense signal
21 PAGING_LED ==> Paging LED control signal SIM_PWR IC pin 22
22 CHARGE_LED ==> Charge LED control signal GEMINI pin 105
23 nRESET ==> MPU nRESET signal
24 CS_LCD ==> LCD chip select signal GEMINI pin 55
25 KBR(3) <== Key Row 3 signal for Key scan GEMINI pin 123
26 KBR(2) <== Key Row 2 signal for Key scan GEMINI pin 124
27 KBR(4) <== Key Row 4 signal for Key scan GEMINI pin 122
28 KBR(1) <== Key Row 1 signal for Key scan GEMINI pin 125
29 KBR(0) <== Key Row 0 signal for Key scan GEMINI pin 126
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
GND
D28V
KEYBKLT
LCD_GRN
LCD_RED
A(1)
RnV
KBC(4)
KBC(3)
KBC(2)
KBC(0)
KBC(1)
D(4)
D(3)
D(2)
D(1)
D(0)
GND
D28V
nPOWKEY
PAGING_LED
CHARGING_LED
nRESET
KBR(3)
KBR(2)
KBR(4)
KBR(1)
KBR(0)
D(5)
D(6)
D(7)
REC_P
REC_N
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
CS_LCD
10075-1

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INTERFACES AND TEST POINTS
Issue A Section 2 MCUK990801G8
Revision 0 – 10 – Technical Guide
GD90 has two external connectors:
1. a multi-way connector for use with a handsfree data;
2. additional contacts for charging the battery pack while in the desktop charger;
All interfaces are electrically and mechanically compatible with GD90.
Main Unit <==> External I/O
30 D(5) <==> MPU Data bus (5)
31 D(6) <==> MPU Data bus (6)
32 D(7) <==> MPU Data bus (7)
33 REC_P ==> Receiver Positive Output
34 REC_N ==> Receiver Negative Output
No. Name H/H <=> EXT Total Function H/H Circuit
1 GND ==> 6 Ground
2 PA_ON ==> 1 Gating of spectrum analyser for Transmitter
performance testing
L: Off, Hi - Z: On)
3 nLOGIC_PWR ==> 1 Accessory Power Control signal.
In the handsfree this is logical OR’ed with
IGNITION in order that the software can
maintain the Handsfree power-on state if the
user is in a call and that the IGNITION is
switched off. L: Power-on, Hi-Z: Power-off
4 IGNITION <== 1 IGNITION is used in two cases.
1) Determine the mode of operation of the H/H
when the Handsfree accessory is attached.
L: At a suitable time enter dummy sleep mode
and therefore minimise the drain on the car
battery (nLOGIC_POWER = Hi - Z)
H: Normal mode
2) Satisfy 2nd of 2 conditions for sending
initialise Testset command and entering Testset
mode. (see nADP_SENSE for 1st condition)
L: Condition 2 satisfied
H: Enter Testset mode not satisfied
5 VBAT <=> 1 The pin is either an input or an output
depending upon the battery connection.
1) Battery/Dummy battery connected: Output
supply terminal for attached accessories.
2) No connection: Low current input supply
terminal for non-RF performance checking in
Testset Mode or Flash programming.
6 nH/F_SENSE <== 1 Handsfree sense line
L: connected
H (internal pull-up): disconnected
7 nRADIO_MUTE ==> 1 Radio Mute
L: mute, Hi-Z: unmute)
8 RX_AUDIO ==> 1 Accessory Receiving Audio
-16 dBm0 = 76.7m Vrms
9 GND ==> Ground Refer to pin 1
No. Signal Name MAIN <=> KEYPAD Function Connection
10095-1
10k
330p
10096-1
330
10097-1
330
50k
200
k
10098-1
10099-1
330
100k
10100-1
330
50k
200
k
10101-1
560
1F
10102-1

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INTERFACES AND TEST POINTS
MCUK990801G8 Section 2 Issue A
Technical Guide – 11 – Revision 0
10 EXT-PWR <== 2 Power supply for battery charging, Power ON/
Off control and accessory control circuits.
Voltage: 5.8 ± 0.2 V
Current: 650 ± 50 mA
11 NON_HOOK <== 1 Indicates if the optional second handset is on or
off hook. In handsfree operation, if the optional
handset is not fitted this signal defaults to on
hook. (Low.)
12 SERIAL_OUT ==> 1 Downlink Serial Data
(Baud rate is same as SERIAL_IN)
13 SERIAL_IN <== 1 Uplink Serial Data
The baud rate is dependant upon the attached
accessory, whether operating in Testset Mode
or Flash Downloading.
SMS cable: 9600 bps
RS232 Direct cable: 38.4 kbps
Data adapter: 33.8 kbps
Testset: 9600 bps
Flash Download: 56 kbps
14 nADP_SENSE <== 1 NADP_SENSE has 5 possible states. The state
is determined by the value of the pull-down
resistor in the attached accessory / test set.
NADP_SENSE has 2 purposes as follows:
1) To identify an attached accessory.
Open (H): No attached accessory
82 kΩ=± 1% (MH): Headset Adapter
56 kΩ=± 1% (M): SMS Cable
33 kΩ=± 1% (ML): RS232C Direct Cable
GND (L): Data Adapter
2) Determine whether the 1st of 2 conditions
are satisfied for sending the initialise Testset
command on SERIAL_OUT, and entering
Testset mode (see IGNITION for 2nd condition).
H/MH: Condition 1 satisfied
M/ML/L: Enter Testset Mode not satisfied
15 NH/F_ON ==> 1 Accessory Sending & Receiving Audio paths
unmute
L: unmute, Hi-Z: mute
16 GND ==> 6 Refer to pin 1 Refer to pin 1
17 TX_AUDIO <== 1 Accessory Sending Audio
-16 dBm0 = 40.4 m Vrms
18 GND ==> 6 Ground connection of Dual Charger Refer to pin 1
No. Name H/H <=> EXT Total Function H/H Circuit
10103-1
Trickle Charge Circuit
Power On/Off Control Circuit
Rapid Charge Circuit
Accessory Control Circuit
330
100k
10100-1
330
2.2k
47k
10104-1
330
4.7 k
10105-1
330
100k
10100-1
330
50k
200
k
10101-1
11 10k
3k3
10106-1

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INTERFACES AND TEST POINTS
Issue A Section 2 MCUK990801G8
Revision 0 – 12 – Technical Guide
Battery Connector
SIM Interface
19 GND ==> 6 Ground connection of Dual Charger Refer to pin 1
20 GND ==> 6 Ground connection of Dual Charger Refer to pin 1
21 GND ==> 6 Ground connection of Dual Charger Refer to pin 1
22 CHARGE_ON <=> 1 The Dual Charger shall hold CHARGE_ON to
the middle level unit a H/H is inserted into the
front slot.
H: 2.0<=V<=3.0 volts; Dual Charger detects
connection of H/H
M: 1.0<=V<2.0 volts; Unconnected
L: 0.0<=V<1.0 volts; Dual Charger detects
connection of H/H
23 EXT_PWR <== 2 The Dual Charger shall control switching of the
power supply to the front slot (corresponds to
EXT_PWR) based on the state of the
CHARGE_ON signal.
H: EXT_PWR supplied
L: When the H/H can determine whether or not
to set CHARGE_ON. After the insertion of the
H/H, EXT_PWR shall be subsequently supplied
withinTBA hours
Refer to pin 8
No. Name H/H <=> EXT Total Function H/H Circuit
1 VBAT <== 1 Positive battery terminal.
Li+ (2 cells in parallel): 3.6 V nom.
NiMH (3 cells in series): 3.6 V nom.
2 BAT_TEMP <== 1 BAT_TEMP has 2 purposes.
1) Determine whether a battery is attached to
the H/H.
2) Monitor battery temperature for the purposes
of charging.
H: Abnormal battery
M: Li+ or NiMH charging
L: No battery or abnormal battery
3 GND <== 1 Negative battery terminal
4 BAT_ID <== 1 BAT_ID is used to identify the type of attached
battery.
H: Li+ or no battery
L: NiMH
Pin Signal
1GND
25V
3 Not connected
4 Reset
5 Serial input/output
6 Clock
7 Not connected
8 Not connected
No. Name H/H <=> EXT Total Function H/H Circuit
10k
330
CHARGE_ON
0.1µ
10107-1
10108-1
ChargerIC VREFOUT
ESD
Vega_ADIN2
ESD
Protection
10109-1
10110-1

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RF OVERVIEW
MCUK990801G8 Section 3 Issue 1
Technical Guide – 7 – Revision 0
3 RF OVERVIEW
3.1 Introduction
3.1.1 General Specifications
GD90 is a Dual Band product incorporating two switchable transceivers, one for the GSM900 band and another for the
GSM1800 (DCS1800) band. The transmit and receive bands for the mobile are given in the table below:
Other salient technical features are as follows:
3.1.2 Description of Main PCB
All components required for the RF and Logic circuits, excluding the LCD module and backlight LEDs, are contained on the
Main PCB. The Main PCB has six layers made from FR4 material (Epoxide woven glass fabric copper-clad laminate as
specified in BS4584 Part 102 and prepeg as specified in BS4584 Part 103). Top and bottom layer tracks are gold-plated to
prevent oxidisation and enable better soldering. The board thickness is 0.9 mm (± 0.1 mm).
The RF components are located on both sides of the upper area of the Main PCB. To provide RF shielding, most of one side
of the Keypad PCB comprises a printed circuit groundplane. The Main board is connected to the Keypad PCB via a 34-way
dual in-line connector. A metallised plastic chassis is used to separate the Main and the Keypad PCB’s. When the chassis is
sandwiched between the Main and the Keypad PCB’s, the groundplane of the Main board together with the chassis forms an
effective shielded enclosure which prevents spurious emissions. The chassis has also been designed to provide smaller walled
sections which are used to isolate sensitive RF areas such as the VCTCXO and the VCO from high level interferers such as
the PA output.
3.2 Functional Description
3.2.1 Frequency Plan
The GD90 frequency plan is shown below
.
Tx Rx
GSM900 890-915 MHz 935-960 MHz
GSM1800 1710-1785 MHz 1805-1880 MHz
GSM900 GSM1800 Units
Rx Bandwidth 25 75 MHz
Tx Bandwidth 25 75 MHz
Duplex Spacing 45 95 MHz
Number of Channels 124 374
ARFCN (Channel Numbers) 1-124 512-885
1st Tx Channel 890.2 1710.2 MHz
Last Tx Channel 914.8 1784.8 MHz
1st Rx Channel 935.2 1805.2 MHz
Last Rx Channel 959.8 1879.8 MHz
Maximum Tx Power 33.0
(Class 4) (PL5)
30.0
(Class 1) (PL0)
dBm
Minimum Tx Power 5.0
(PL19)
0.0
(PL15)
dBm
Tx Tx IF RFLO Tx IFLO Tx Unit
GSM900 890-915 270 1160-1185 540 MHz
GSM1800 1710-1785 130 1580-1655 520 MHz
Rx Rx 1st IF Rx 2nd IF RFLO Rx IFLO Rx Unit
GSM900 935-960 225 45 1160-1185 540 MHz
GSM1800 1805-1880 225 45 1580-1655 540 MHz

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RF OVERVIEW
Issue A Section 3 MCUK990801G8
Revision 0 – 14 – Technical Guide
Figure 3.1: RF Block Diagram
V_PAON
DATA
I
Q
RAMP DATA
IF SAW
Demod
PGC
(225MHz)
PHASE
DETECTOR
To
PLL IC
Ref.
Clock
AFC
I
Q
TX DUAL VCO
UY76044
LOOP
FILTER
LOOP
FILTER
1/2
1/2 1/6
13MHz
1/2
PCNnGSM
CLOCK
STROBE
PCNnGSM
PCNnGSM
V_PAON
DATA
CLOCK
STROBE
PCNnGSM
GSM:540MHz
DCS TX:520MHz RX:540MHz
GSM:1160~1185MHz
DCS:1580~1655MHz
45MHz
GSM:890~915MHz
DCS:1710~1785MHz
ANT
GSM
LNA
DCS
LNA
(DCS)
EFCH225MDQP2
(MACO)
PLL
IC
PCNnGSM
PGC Gain
PCNnGSM
TXON1 RXON1 RXON2
2nd LOCAL VCO
(MACO)
10076-1
PLL IC
MB15F03SL
[SSOP Package]
(Fujitsu)
Diplexer + 2
SW
LMC36-07A0503A
(MURATA)
(GSM)
DUAL LOCAL VCO
UY76043A
(MACO)
DUAL RX SAW
Filter 3.8*3.8mm
(MACO)
DUAL LNA IC
GN01073B
(MEC)
DUAL RX SAW
3.8*3.8mm
(MACO)
DCS
Mixer
2nd
Mixer
GSM Mixer
HITACHI
BRIGHT-2
HD155123F
13MHz VCXO
7.0*5.0mm
(NDK)
3 wire bus control
1st, 2nd Mixer Gain
I&Q
MODULATOR
LOOP
FILTER
PCNnGSM
DC
MIXER
DUAL TX SAW
Filter
3.8*3.8mm
(MACO)
Exciter
MGA-81563
(HP)
LPF Coupler
(GSM)
LDC15H200J0897
(MURATA)
Dual PA
PF08103B
(HITACHI)
LPF Coupler
(DCS)
LDC15H200J0897
(MURATA)
DUAL APC IC
HD155171T
(HITACHI)

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RF OVERVIEW
MCUK990801G8 Section 3 Issue A
Technical Guide – 15 – Revision 0
Figure 3.2: GSM 900 Frequency Plan
Figure 3.3: GSM 1800 Frequency Plan
3.2.2 General
The major building blocks for the RF design are the Hitachi transmit (Tx) and receive (Rx) IC, Fujitsu RF-IF dual PLL and the
antenna subsystem.
In either receiver band, GSM900 or GSM1800, the Rx 1st IF is fixed at 225 MHz and 2nd IF at 45 MHz. Therefore, the 2nd
local oscillator is fixed at 540 MHz for receive mode.
In GSM900 transmit mode, the 2nd LO is reprogrammed to 540 MHz, the same for receive mode.
In GSM1800 mode, the 2nd local oscillator is re-programmed to 520 MHz. For this choice of IF, no transmitter in-band spurious
is believed to occur due to harmonics of the 1st LO.
The Tx VCO will be on-channel in either GSM900 or GSM1800 modes of operation.
935-960MHz
RF LO
1160-1185MHz
TX VCO
890-915MHz Fcomparison
270MHz
Fdiff
270MHz
Rx 1st IF
225MHz
IF LO
VCO
540MHz
Rx 2nd IF
45MHz
÷2
45MHz
270MHz
I
Q
I
Q
÷2 ÷6
90MHz
÷2
270MHz
10077-1
1805-1880MHz
RF LO
1580-1655MHz
TX VCO
1710-1785MHz Fcomparison
130MHz
Fdiff
130MHz
Rx 1st IF
225MHz
IF LO VCO
Rx: 540MHz
Tx: 520MHz
Rx 2nd IF
45MHz
÷2
45MHz
270MHz
I
Q
I
Q
÷2 ÷6
90MHz
÷2
260MHz
10078-1

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RF OVERVIEW
Issue 1 Section 3 MCUK990801G8
Revision 0 – 10 – Technical Guide
3.2.3 Antenna
The antenna is a fixed helical type.
A mechanical RF switch is used to route the RF signal from the external antenna for handsfree operation and test purposes.
3.2.4 Transmit and Receive
The transmit and receive paths of GD90 are covered in their own specific chapters later in this manual.
3.3 RF & Accessory Connector
In previous models the RF signal is routed to the accessory connector which contains a micro-switch. If the switch is open, the
RF signal is routed to the hands free unit. If it closed, the signal is routed back via the Main PCB to the antenna. This routing
of the RF signal up and down the Main PCB invariably has a finite power loss associated with it.
In addition, the GD90 has a limited PCB area and the routing of the RF signal in this way reduces further the available PCB
area required for the Dual Band circuit.
To alleviate these problems the RF connector is located close to the PA module. This reduces the loss and hence the PAs do
not have to be driven so hard. This allows the power supply voltage to be lower, thus improving battery performance.

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TRANSMITTER
MCUK990801G8 Section 4 Issue 1
Technical Guide – 11 – Revision 0
4 TRANSMITTER
4.1 Introduction
This section provides a technical description of the transmitter circuit of the RF circuit. A circuit diagram of the whole system is
provided in the Service Manual.
The uplink frequencies for the GSM 900 and GSM 1800 can be calculated as follows:
4.1.1 Uplink Frequencies GSM 900
Uplink frequency = 890 MHz + (ARFCN x 0.2 MHz)
e.g. for CH55
890 MHz + (55 x 0.2 MHz)
= 890 MHz + (11 MHz)
= 901 MHz
4.1.2 Uplink Frequencies GSM 1800
Uplink frequency = 1710 MHz + ((ARFCN - 511) x 0.2 MHz)
e.g. for CH512
1710 MHz + ((512 - 511) x 0.2 MHz)
= 1710 MHz + (0.2 MHz)
= 1710.2 MHz
CHANNEL
NUMBERS UPLINK FREQUENCIES (MHz)
1-5
6-10
11-15
16-20
21-25
890.200
891.200
892.200
893.200
894.200
890.400
891.400
892.400
893.400
894.400
890.600
891.600
892.600
893.600
894.600
890.800
891.800
892.800
893.800
894.800
891.000
892.000
893.000
894.000
895.000
26-30
31-35
36-40
41-45
46-50
895.200
896.200
897.200
898.200
899.200
895.400
896.400
897.400
898.400
899.400
895.600
896.600
897.600
898.600
899.600
895.800
896.800
897.800
898.800
899.800
896.000
897.000
898.000
899.000
900.000
51-55
56-60
61-65
66-70
71-75
900.200
901.200
902.200
903.200
904.200
900.400
901.400
902.400
903.400
904.400
900.600
901.600
902.600
903.600
904.600
900.800
901.800
902.800
903.800
904.800
901.000
902.000
903.000
904.000
905.000
76-80
81-85
86-90
91-95
96-100
905.200
906.200
907.200
908.200
909.200
905.400
906.400
907.400
908.400
909.400
905.600
906.600
907.600
908.600
909.600
905.800
906.800
907.800
908.800
909.800
906.000
907.000
908.000
909.000
910.000
101-105
106-110
111-115
116-120
121-124
910.200
911.200
912.200
913.200
914.200
910.400
911.400
912.400
913.400
914.400
910.600
911.600
912.600
913.600
914.600
910.800
911.800
912.800
913.800
914.800
911.000
912.000
913.000
914.000

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TRANSMITTER
Issue A Section 4 MCUK990801G8
Revision 0 – 18 – Technical Guide
4.2 Functional Description
Figure 4.1: Transmitter
The transmitter design is based on an IQ Modulator and operates at Class 4 (2W) in the GSM 900 band and at Class 1 (1W)
in the GSM 1800 band. The architecture has been carefully chosen to enable the GSM transmitter noise in receiver band
requirements to be met without the need for a duplexer.
The RF IC Bright2 provides the following transmitter functions:
I, Q Quadrature modulator
Down conversion mixer for modulated signal to intermediate frequency
Phase detector for the PLL modulation loop.
The IF LO signal generated by the IF VCO is modulated by the baseband I,Q signals in the quadrature modulator. Output from
the quadrature modulator is fed into the phase detector for the PLL modulation loop.
The output from the Tx VCO is fed into the down conversion mixer and is converted with the 1st LO signal which is generated
by the 1st VCO to IF frequency. The output signal from the down conversion mixer is fed into the phase detector for the PLL
modulation loop.
The charge pump output signal produced by the phase detector is fed back to the Tx VCO to generate modulated RF output.
The output from the Tx VCO is filtered before it is applied to the PA driver. This ensures that spurious emissions are well within
GSM specifications.
Output from the PA driver is amplified by the PA to any required level up to PL5 (33 dBm at the antenna) for GSM 900 and PL0
(30 dBm) for GSM 1800. PA output is applied to the antenna via a low-pass filter to remove unwanted harmonics.
A discrete diplexer is used after the PA buffer which provides low pass filtering for the 900 MHz band and high pass filtering
for the 1800 MHz band. The switching between the receiver and the transmitter for any band is achieved by means of pin diode
switches. The antenna ports of these switches are connected to the antenna or the handsfree RF connector. The hands free
connector incorporates a mechanical switch which enables the signal to be routed either to the antenna or to the hands free
connector depending on the operation required.
The RF LO is also a modular VCO which contains two VCOs, one for the 900 MHz band and the other for the 1800 MHz band.
The operation is similar to the Tx VCO in that the required RF VCO is switched by two control lines.
The IF VCO is a discrete design. Both the RF and IF LOs are designed around a dual PLL with the IF frequency range up to
600 MHz and the RF frequency range up to 2 GHz.
IQ
Modulator
Loop
Filter
Phase
Detector
Dual Tx SAW
Filter
FL101
Diplexer
S101
Coupler
E101
900
1800
900
1800
Dual Band
Tx VCO
U102 Coupler
E102
Dual Band PA
U104
Exciter
U103
Antenna
+ Sw.
DC
Mixer
Dual Band Receiver (PART)
U101
10086-1

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TRANSMITTER
MCUK990801G8 Section 4 Issue A
Technical Guide – 19 – Revision 0
4.2.1 GSM 900 Signal Levels
Figure 2.2: GSM 900 Transmitter Signal Levels
4.2.2 GSM 1800 Signal Levels
Figure 2.3: GSM 1800 Transmitter Signal Levels
-15
-10
-5
0
5
10
15
20
25
30
35
40
Dual TX
VCO
Power
sprit
ATTN BPF Excitor ATT PA Coupler SW-
Diplexer
ANT
(dBm)
Typical case
Worst case
10083-1
-15
-10
-5
0
5
10
15
20
25
30
35
Dual TX
VCO
Power
sprit
ATTN BPF Excitor ATT PA Coupler SW-
Diplexer
ANT
(dBm)
Typical case
Worst case
10084-1

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RECEIVER
MCUK990801G8 Section 5 Issue 1
Technical Guide – 15 – Revision 0
5 RECEIVER
5.1 Introduction
This Section provides a technical description of the receiver section of the RF circuit. A complete circuit diagram is provided in
the Service Manual.
The downlink frequencies for the GSM 900 and GSM 1800 bands can be calculated as follows:
5.1.1 Downlink Frequencies GSM 900
Downlink frequency = 935 MHz + (ARFCN x 0.2 MHz)
e.g. for CH55
935 MHz + (55 x 0.2 MHz)
= 935 MHz + (11 MHz)
= 946 MHz
5.1.2 Downlink Frequencies GSM 1800
Downlink frequency = 1805 MHz + ((ARFCN - 511) x 0.2 MHz)
e.g. for CH512
1805 MHz + ((512 - 511) x 0.2 MHz)
= 1805 MHz + (0.2 MHz)
= 1805.2 MHz
CHANNEL
NUMBERS DOWNLINK FREQUENCIES (MHz)
1-5
6-10
11-15
16-20
21-25
935.200
936.200
937.200
938.200
939.200
935.400
936.400
937.400
938.400
939.400
935.600
936.600
937.600
938.600
939.600
935.800
936.800
937.800
938.800
939.800
936.000
937.000
938.000
939.000
940.000
26-30
31-35
36-40
41-45
46-50
940.200
941.200
942.200
943.200
944.200
940.400
941.400
942.400
943.400
944.400
940.600
941.600
942.600
943.600
944.600
940.800
941.800
942.800
943.800
944.800
941.000
942.000
943.000
944.000
945.000
51-55
56-60
61-65
66-70
71-75
945.200
946.200
947.200
948.200
949.200
945.400
946.400
947.400
948.400
949.400
945.600
946.600
947.600
948.600
949.600
945.800
946.800
947.800
948.800
949.800
946.000
947.000
948.000
949.000
950.000
76-80
81-85
86-90
91-95
96-100
950.200
951.200
952.200
953.200
954.200
950.400
951.400
952.400
953.400
954.400
950.600
951.600
952.600
953.600
954.600
950.800
951.800
952.800
953.800
954.800
951.000
952.000
953.000
954.000
955.000
101-105
106-110
111-115
116-120
121-124
955.200
956.200
957.200
958.200
959.200
955.400
956.400
957.400
958.400
959.400
955.600
956.600
957.600
958.600
959.600
955.800
956.800
957.800
958.800
959.800
956.000
957.000
958.000
959.000

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RECEIVER
Issue A Section 5 MCUK990801G8
Revision 0 – 22 – Technical Guide
5.2 Functional Description
The main building block for the Dual Band Receiver is the Hitachi Bright2 IC. The receiver is a double superhet type with the
1st IF at 225 MHz and 2nd IF at 45 MHz. The intermediate frequencies are common to both frequency bands.
The Rx IC contains the following stages:
1. Gain controlled 1st mixer for GSM 900 band.
2. Gain controlled 1st mixer for GSM 1800 band.
3. Gain controlled 2nd mixer.
4. Gain controlled IF amplifier
5. I,Q quadrature down converter.
6. Baseband Op Amps for further amplification and some filtering of the baseband I,Q signals.
5.2.1 Dual Band Receiver
Figure 5.1: Dual Band Receiver
RF input to the receiver is either via the antenna or via the H/F RF connector for test purposes. The input signal from the
antenna or the H/F RF connector is fed into the GSM 900/GSM 1800 dual band LNA MMIC via the Diplexer port, Tx/Rx
switches to the dual band Rx SAW filter. The diplexer band splits the two GSM frequency bands whilst the pin switches route
the signal flow from the receiver and the transmitter as required. The receiver 1st SAW filter provides the roofing filter for the
Rx front end.
The dual band LNA gain is constant, typically 18 dB for GSM 900 and 17dB for GSM 1800. Noise factor is typically 1.5dB for
both bands. Operation of the dual band LNA is controlled directly by the PCNnGSM band switch signal.
The output from the LNA passes through a dual BP SAW filter and is then fed into the 1st mixer for each band. Both mixers
are controlled by a 3-wire bus, typically providing between +9.5dB and -2dB gain for GSM900, and between +8.5dB and -3.5dB
for GSM 1800.
The IF output at 225 MHz from the 1st mixer is filtered by the differential IF SAW filter before it is fed into the 2nd mixer. The
use of differential filters eliminates the need for baluns and provides some cost and space advantage. The 2nd mixer is also
gain controlled from a 3-wire bus, typically between +13dB and -3.0dB. Gain switching is synchronised with the 1st mixer.
Output from the 2nd mixer at 45 MHz is filtered by an L-C network before it is fed to the gain controlled IF amplifiers.The IF
amplifier is gain controlled by a three-wire bus from -29 to +69 dB in 2 dB steps. This function is used for AGC purposes.
The output from IF amplifiers is fed into two quadrature mixers where it is converted down to baseband. The IF LO is generated
at 540 MHz by an external discrete VCO module. An on-chip divider on the Rx IC divides this six and then by two. It also
produces two outputs in quadrature to generate the baseband I and Q signals. The outputs from the mixers are connected to
external pins through a pair of buffers. Two on-chip Op Amps are used to amplify the AC signal from the mixers to meet the
overall signal performance requirements.
The DC level at the output of the Op Amps is 1.35 V with a 200 mV p-p single ended AC swing controlled by the AGC loop to
maintain optimum receiver performance.
GSM 900
DUAL
LNA
U203
PGC
GSM 1800 1800
DUAL RX
SAW
FL203
DUAL BAND RECEIVER (PART)
U101
FL200
IF
SAW
1st
Mixer 2nd Mixer
900
1800
900
LPF Rx
Tx
Rx
Tx
Ext
Ant.
HPF
10085-1
S101
DUAL Rx
SAW
FL201
DIPLEXER
I
Q
Demodulator

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RECEIVER
MCUK990801G8 Section 5 Issue A
Technical Guide – 23 – Revision 0
5.2.2 GSM 900 Signal Levels
The signal levels through the receiver IC for the GSM 900 band are given below.
Figure 5.2: GSM 900 Nominal and Worst Case Signal Levels
5.2.3 GSM 1800 Signal Levels
The signal levels through the receiver IC for the GSM 1800 are given below.
Figure 5.3: GSM 1800 Nominal and Worst Case Signal Levels
-120.0
-110.0
-100.0
-90.0
-80.0
-70.0
-60.0
-50.0
-40.0
-30.0
-20.0
-10.0
0.0
10.0
ANT DIPLEX +
SW
RX
BPF
LNA RX
BPF
MIX IF
SAW
2nd
MIX
2nd
IF FL
IF
AGC
I/Q
Demod
(dBm)
Typical Case
Worst Case
Large Signal
10081-1
DCS RX Level Diagram
-120.0
-110.0
-100.0
-90.0
-80.0
-70.0
-60.0
-50.0
-40.0
-30.0
-20.0
-10.0
0.0
10.0
ANT DIPLEX +
SW
RX
BPF
LNA RX
BPF
MIX IF
SAW
2nd
MIX
2nd
IF FL
IF
AGC
I/Q
Demod
(dBm)
Typical Case
Worst Case
Large Signal
10082-1

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BASEBAND OVERVIEW
MCUK990801G8 Section 6 Issue A
Technical Guide – 25 – Revision 0
6 BASEBAND OVERVIEW
6.1 Introduction
The main Baseband circuitry is located with the RF circuits on the Main PCB, while the baseband sub-circuits, comprising keys
and LCD backlights, are located on the Keypad PCB.
A metallised plastic chassis is used to separate the Main and the Keypad PCBs. The continuous chassis design is important
for EMC purposes. When the chassis is sandwiched between the two PCB assemblies, the groundplane of the Keypad PCB
together with the chassis forms an effective shielded enclosure, preventing spurious emissions.
6.2 Functional Description of the PCB
The GD90 baseband is based around a two-chip GSM chipset developed by Texas Instruments. One chip (GEMINI) carries
out signal processing with DSP and CPU, and the other chip (VEGA3) contains the analogue interface chip. The highly
integrated nature of these components means each contain a large number of functions.
Figure 6.1: Baseband Block Diagram
TEST &
EMULATION
TEST &
EMULATION
CPU
CORE
BURST
STORE
ANTIALIASING
FILTER
GMSK
MOD
8-Bit
I DAC
8-Bit
Q DAC
DIFF
ENCODE
XIO
INTH
nLVA_INT
DAI RST
T
S
P
A
C
T
APIF
ARM
CORE
MICROWIRE
I/F
SYSTEM
SIMULATOR
DATA
ADAPTER
TESTSET
TEST
MOBILE
SIM
CARD
VIBRATOR MEMORY
I/F
TDM
TIME-
BASE
TPU
TIMER
BUZZER
BACK-
LIGHT
KEYPAD
CLKM SLICER
VOICE
MEMO FLASH 1M*16 SRAM 256K*8 LCD EXTENDED OUTPUT
13MHz
POWER ON/OFF
CONTROL &
POWER SOURCE
FAILURE CIRCUIT
RAPID CHARGE
& BATTERY
MONITORING
CIRCUIT
TRICKLE
CHARGE
CIRCUIT
JTAG
EEPROM
2K*8
XIO
ROM
&
RAM
JTAG PLL &
CLOCKS
IRQ API SPI
LEAD Megamodule
GEMINI VEGA
UART
SIM
I/F
5V
DC/DC
CONVERTER
+ LEVEL
SHIFTER
I/O
INTER PCB CONNECTOR
BATTERY
INTER PCB CONNECTOR ACCESSORY
CONNECTOR
ACCESSORY
CONNECTOR
IGNITION nHF_SENSE nLOGIC_PWR EXT_PWR BAT_ID
BAT_VOLT CURRENT
VSET
BAT_TEMP VBAT
LPF
LPF
FILTER
DSP SERIAL I/F
INTER PCB CONNECTOR
SIGMA-DELTA
ANTIALIASING
FILTER
FILTER
MCU
SERIAL I/F
VOICEBAND
SERIAL I/F
SIGMA-DELTA
SIGMA-DELTA
APC
(D/A)
AFC
(D/A)
DAI SYSTEM
SIMULATOR
AGC
(D/A) TEST
INTERNAL REGISTERS
BPF LPF
SIGMA-DELTA
BPF
SLICER 5 INPUT
10-BIT A/D
TX_AUDIO RX_AUDIO
ULI
ULQ
DLI
DLQ
PARAMP
AFC
10075-1

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BASEBAND OVERVIEW
Issue A Section 6 MCUK990801G8
Revision 0 – 26 – Technical Guide
6.2.1 Keypad
The Keypad has a 5 x 5 matrix in rows and columns, allowing 25 keys to be scanned. Each row has a built-in pull-up resistor
and the column line outputs are selected low. On a key press, the row input is pulled low by the corresponding column
generating a keypad interrupt. To ascertain which key has been pressed, the software asserts all columns high then takes each
one low. While each column is held low the rows are polled to see which one has been pulled low.
As the END key doubles as ON / OFF key, it is allocated an entire row of the keyboard scan.
To eliminate false key presses, i.e. key bounce, the key has to remain pressed for a minimum of 20 ms.
Keyboard scanning is software controlled. Key pressed is indicated by an interrupt, but key release is controlled by software.
Figure 6.2: Keypad Matrix
6.2.2 Subscriber Identity Module (SIM)
The SIM interface is designed to support 3 V and 5 V SIMs.
The GD90 GEMINI process is unable to support 5 V tolerant inputs. Therefore, in order to Interface GEMINI with a 2.8 V supply,
and the SIM with a 5 V supply, it is necessary to include a level shift. U505 is able to perform the required level shift. In addition
the device includes a switched capacitor charge pump DC/DC converter to generate the 5 V SIM supply from D2V8.
The SIM is initially activated by U505 with a 3 V supply and checks Status identification after receiving an ATR command. If
U505 detects a 3 V technology SIM, it operates it at 3 V. If a 5 V SIM, operation is switched to 5 V. If a faulty ATR is received
at 3 V, an error handling procedure is initiated. If the error handling does not result in an errorless ATR, the SIM is activated at
5 V. If no ATR is received at 3 V, the SIM will be deactivated and re-actived at 5 V.
43
D722 VOICE_MEMO
*
S701
7
S706
TP757
TP762 TP763 2
4
S711
TP764 10
1
S716
TP765 TP766
D729
PWR/END
0
0
S702
8
S707
TP758
5
S712
2
S417
1
#
S703
9
S708
TP759
6
S413
3
S718
2
OK
S704
<
S709
TP760
v
S714
SND
S719
3
CLR
S705
S721
nPOWKEY
>
S710
TP761
TP767
v
S715
PB
S720
43
12
4
KBC(0:4)
KBR(0:4)
10067-1