LG U8290 Service Manual
Date: August, 2005 / Issue 1.0
Service Manual
U8290
Service Manual
Model : U8290
- 3 -
1. INTRODUCTION .............................. 6
1.1 Purpose................................................... 6
1.2 Regulatory Information............................ 6
2. PERFORMANCE.............................. 8
2.1 System Overview .................................... 8
2.2 Usable Environment................................ 9
2.3 Radio Performance ................................. 9
2.4 Current Consumption............................ 15
2.5 RSSI Bar ............................................... 15
2.6 Battery Bar ............................................ 15
2.7 Sound Pressure Level........................... 16
2.8 Charging ............................................... 17
3. TECHNICAL BRIEF ....................... 18
3.1 General Description .............................. 18
3.2 GSM Mode............................................ 21
3.2.1 GSM Receiver ................................ 21
3.2.2 GSM Transmitter............................. 24
3.3 WCDMA Mode ...................................... 25
3.3.1 Receiver.......................................... 25
3.3.2 Transmitter...................................... 28
3.4 LO Phase-locked Loop ......................... 29
3.4.1 UMTS Rx PLL (PLL2) ..................... 29
3.4.2 Transceiver PLL (PLL1).................. 30
3.5 Off-chip RF Components ...................... 31
3.5.1 Antenna switch module................... 31
3.5.2 UMTS duplexer .............................. 31
3.5.3 UMTS Power Amplifier.................... 32
3.5.4 Thermistor....................................... 33
3.5.5 UMTS transmit power detector ....... 33
3.5.6 Dual band GSM power amplifier .... 34
3.5.7 GSM transmit VCO ......................... 36
3.5.8 UMTS Rx RF filter........................... 36
3.5.9 GSM band Rx RF filter ................... 37
3.5.10 VCTCXO....................................... 37
3.5.11 UMTS Rx VCO.............................. 37
3.5.12 Bluetooth....................................... 37
3. BB Technical Description............. 39
3.6 Digital Baseband................................... 39
3.6.1 General Description ........................ 39
3.7 Hardware Architecture .......................... 40
3.7.1 Block Diagram ................................ 41
3.8 Subsystem(MSM6250) ......................... 42
3.8.1 ARM Microprocessor Subsystem.... 42
3.8.2 UMTS Subsystem........................... 42
3.8.3 GSM Subsystem............................. 42
3.8.4 RF Interface .................................... 42
3.8.5 Serial Bus Interface(SBI) ................ 42
3.8.6 Wideband CODEC.......................... 43
3.8.7 Vocoder Subsystem........................ 43
3.8.8 HKADC ........................................... 43
3.8.9 Mode Select and JTAG Interfaces.. 43
3.8.10 General-Purpose Input/Output
Interface ........................................ 43
3.8.11 UART ............................................ 44
3.8.12 USB .............................................. 44
3.9 External memory interface ................... 45
3.10 H/W Subsystem .................................. 46
3.10.1 RF Interface .................................. 46
3.10.2 MSM Subsystem........................... 48
3.10.3 Power Block.................................. 51
3.10.4 Key Pad ........................................ 56
3.10.5 Camera Interface .......................... 57
3.10.6 Folder ON/OFF Operation ............ 59
3.10.7 Camera Direction Detection.......... 60
3.10.8 Keypad Light................................. 61
3.10.9 Camera Light Flash ...................... 62
Table Of Contents
Table Of Contents
- 4 -
3.10.10 LCD Module................................ 63
3.10.11 Audio and Sound ........................ 65
4. TROUBLE SHOOTING .................. 78
4.1 RF Component...................................... 78
4.2 SIGNAL PATH ...................................... 80
4.3 Checking VCXO(19.2MHz) Block ......... 81
4.4 Checking Ant. SW Module Block .......... 83
4.5 Checking WCDMA Block ...................... 85
4.5.1 Checking VCXO Block ................... 86
4.5.2 Checking Ant. SW module.............. 86
4.5.3 Checking RF TX Level ................... 86
4.5.4 Checking PAM Block ...................... 88
4.5.5 Check RF Rx Level ........................ 89
4.6 Checking GSM Block ............................ 91
4.6.1 Checking TXVCO Block.................. 92
4.6.2 Checking Ant. SW Module ............. 94
4.6.3 Checking RF Tx level ..................... 94
4.6.4 Checking PAM Block ..................... 96
4.6.5 Checking RF Rx Block ................... 97
4.7 Bluetooth RF Block ............................... 99
4.8 LG-U8290 Main features..................... 102
4.9 LG-U8290 Main Component ............... 103
4.10 Power ON Trouble ............................ 107
4.11 USB Trouble ..................................... 109
4.12 SIM Detect Trouble ........................... 111
4.13 Key Sense Trouble ........................... 112
4.14 Camera Trouble ................................ 113
4.15 Main LCD Trouble............................. 114
4.16 Sub LCD Trouble .............................. 116
4.17 Keypad Backlight Trouble ................. 118
4.18 Folder ON/OFF Trouble .................... 119
4.19 Camera Direction Detection Trouble. 121
4.20 Camera Flash Trouble ...................... 123
4.21 Audio Trouble Shooting .................... 125
4.22 Charger Trouble Shooting................. 144
5. BLOCK DIAGRAM ....................... 150
5.1 GSM & WCDMA RF Block.................. 150
5.2 Interface Diagram ............................... 152
6. DOWNLOAD ................................ 156
6.1 Introduction ......................................... 156
6.2 Downloading Procedure...................... 156
6.3 Troubleshooting Download Errors ...... 169
6.4 Caution................................................ 174
7. CALIBRATION ............................. 175
7.1 General Description ............................ 175
7.2 Pegasus Environment......................... 175
7.2.1 H/W Environment.......................... 175
7.2.2 S/W Environment.......................... 175
7.2.3 Configuration Diagram of
Calibration Environment................ 175
7.3 Calibration Explanation ....................... 176
7.3.1 Overview....................................... 176
7.3.2 Calibration Items........................... 176
7.3.3 EGSM 900 Calibration Items ........ 177
7.3.4 DCS 1800 Calibration Items ......... 179
7.3.5 PCS 1900 Calibration Items ......... 180
7.3.6 WCDMA Calibration Items............ 182
7.4 Program Operation ............................. 187
7.4.1 Pegasus Program Overview ......... 187
7.4.2 Pegasus Function Description ...... 187
7.4.3 Calibration Procedure ................... 192
7.4.4 Calibration Result Message.......... 192
7.4.5 Pegasus Configuration File Format .. 193
8. CIRCUIT DIAGRAM ..................... 195
Table Of Contents
- 5 -
9. PCB LAYOUT............................... 203
10. EXPLODED VIEW &
REPLACEMENT PART LIST ..... 208
10.1 EXPLODED VIEW ............................ 208
10.2 Replacement Parts
<Mechanic component>.................... 209
<Main component> ........................... 214
10.3 Accessory ......................................... 232
1. INTRODUCTION
- 6 -
1.1 Purpose
This manual provides the information necessary to repair, calibration, description and download the
features of this model.
1.2 Regulatory Information
A. Security
Toll fraud, the unauthorized use of telecommunications system by an unauthorized part (for example,
persons other than your company’s employees, agents, subcontractors, or person working on your
company’s behalf) can result in substantial additional charges for your telecommunications services.
System users are responsible for the security of own system. There are may be risks of toll fraud
associated with your telecommunications system. System users are responsible for programming and
configuring the equipment to prevent unauthorized use. The manufacturer does not warrant that this
product is immune from the above case but will prevent unauthorized use of common-carrier
telecommunication service of facilities accessed through or connected to it. The manufacturer will not
be responsible for any charges that result from such unauthorized use.
B. Incidence of Harm
If a telephone company determines that the equipment provided to customer is faulty and possibly
causing harm or interruption in service to the telephone network, it should disconnect telephone
service until repair can be done. A telephone company may temporarily disconnect service as long as
repair is not done.
C. Changes in Service
A local telephone company may make changes in its communications facilities or procedure. If these
changes could reasonably be expected to affect the use of the phones or compatibility with the
network, the telephone company is required to give advanced written notice to the user, allowing the
user to take appropriate steps to maintain telephone service.
D. Maintenance Limitations
Maintenance limitations on the phones must be performed only by the manufacturer or its authorized
agent. The user may not make any changes and/or repairs expect as specifically noted in this manual.
Therefore, note that unauthorized alternations or repair may affect the regulatory status of the system
and may void any remaining warranty.
1. INTRODUCTION
1. INTRODUCTION
- 7 -
E. Notice of Radiated Emissions
This model complies with rules regarding radiation and radio frequency emission as defined by local
regulatory agencies. In accordance with these agencies, you may be required to provide information
such as the following to the end user.
F. Pictures
The pictures in this manual are for illustrative purposes only; your actual hardware may look slightly
different.
G. Interference and Attenuation
A phone may interfere with sensitive laboratory equipment, medical equipment, etc.
Interference from unsuppressed engines or electric motors may cause problems.
H. Electrostatic Sensitive Devices
ATTENTION
Boards, which contain Electrostatic Sensitive Device (ESD), are indicated by the sign.
Following information is ESD handling:
• Service personnel should ground themselves by using a wrist strap when exchange system boards.
• When repairs are made to a system board, they should spread the floor with anti-static mat which is
also grounded.
• Use a suitable, grounded soldering iron.
• Keep sensitive parts in these protective packages until these are used.
• When returning system boards or parts like EEPROM to the factory, use the protective package as
described.
2. PERFORMANCE
- 8 -
2.1 System Overview
2. PERFORMANCE
Item Specification
Shape GSM900/1800/1900 and WCDMA Folder Handset
Size 89.2 X 47.8 X 24.5 mm
Weight 115 g (with Battery)
Power 4.0V normal, 1400 mAh Li-Polymer
Talk Time
Over 170 min (WCDMA, Tx=12 dBm, Voice)
Over 220 min (GSM, Tx=Max, Voice)
Standby Time
Over 170 Hrs (WCDMA, DRX=1.28)
Over 250 Hrs (GSM, Paging period=9)
Antenna Fixed Type (Fixed Screw)
LCD Main 176 X 220 pixel (TFT) / sub 96 X 96 pixel (CSTN)
LCD Backlight White LED Back Light (2way ; main/sub common)
Camera 1.3 Mega pixel (CMOS)
Vibrator Yes (Coin Type)
LED Indicator No
C-MIC Yes
Receiver Yes
Earphone Jack Yes (12 pin)
Connectivity Bluetooth, USB
Volume Key Push Type(+, -)
External Memory Trans-Flash
I/O Connect 24 Pin
2. PERFORMANCE
- 9 -
2.2 Usable environment
1) Environment
2) Environment (Accessory)
* CLA : 12 ~ 24 V(DC)
2.3 Radio Performance
1) Transmitter - GSM Mode
* In case of DCS : [A] -> 1710, [B] -> 1785 * In case of PCS : [A] -> 1850, [B] -> 1910
Item Spec.
Voltage 4.0 V(Typ), 3.38 V(Min), [Shut Down : 3.28 V]
Operation Temp -20 ~ +60 °C
Storage Temp -30 ~ +85 °C
Humidity 85 % (Max)
Item Spec. Min Typ. Max Unit
TA Power Available power 100 220 240 Vac
No Item GSM DCS & PCS
100k~1GHz -39dBm
9k ~ 1GHz -39dBm
MS allocated 1G~[A]MHz -33dBm
Channel
1G~12.75GHz -33dBm
[A]M~[B]MHz -39dBm
Conducted [B]M~12.75GHz -33dBm
1Spurious 100k~880MHz -60dBm 100k~880MHz -60dBm
Emission 880M~915MHz -62dBm 880M~915MHz -62dBm
Idle Mode
915M~1GHz -60dBm 915M~1GHz -60dBm
1G~[A]MHz -50dBm 1G~[A]MHz -50dBm
[A]M~[B]MHz -56dBm [A]M~[B]MHz -56dBm
[B]M~12.5GHz -50dBm [B]M~12.5GHz -50dBm
2. PERFORMANCE
- 10 -
* In case of DCS : [A] -> 1710, [B] -> 1785 * In case of PCS : [A] -> 1850, [B] -> 1910
No Item GSM DCS & PCS
30M ~ 1GHz -36dBm
30M~1GHz -36dBm
MS allocated 1G~[A]MHz -30dBm
Channel
1G ~ 4GHz -30dBm
[A]M~[B]MHz -36dBm
Radiated [B]M~4GHz -30dBm
2Spurious 30M ~ 880MHz -57dBm 30M~880MHz -57dBm
Emission 880M ~ 915MHz -59dBm 880M~915MHz -59dBm
Idle Mode
915M~1GHz -57dBm 915M~1GHz -57dBm
1G~[A]MHz -47dBm 1G~[A]MHz -47dBm
[A]M~[B]MHz -53dBm [A]M~[B]MHz -53dBm
[B]M~4GHz -47dBm [B]M~4GHz -47dBm
3 Frequency Error ±0.1ppm ±0.1ppm
4 Phase Error
±5(RMS) ±5(RMS)
±20(PEAK) ±20(PEAK)
3dB below reference sensitivity 3dB below reference sensitivity
Frequency Error RA250 : ±200Hz RA250: ±250Hz
5 Under Multipath and HT100 : ±100Hz HT100: ±250Hz
Interference Condition TU50 : ±100Hz TU50: ±150Hz
TU3 : ±150Hz TU1.5: ±200Hz
0 ~ 100kHz +0.5dB 0 ~ 100kHz +0.5dB
200kHz -30dB 200kHz -30dB
250kHz -33dB 250kHz -33dB
Due to 400kHz -60dB 400kHz -60dB
Output RF
modulation 600 ~ 1800kHz -66dB 600 ~ 1800kHz -60dB
6 1800 ~ 3000kHz -69dB 1800 ~ 6000kHz -65dB
Spectrum
3000 ~ 6000kHz -71dB ≥6000kHz -73dB
≥6000kHz -77dB
Due to
400kHz -19dB 400kHz -22dB
Switching
600kHz -21dB 600kHz -24dB
transient
1200kHz -21dB 1200kHz -24dB
1800kHz -24dB 1800kHz -27dB
2. PERFORMANCE
- 11 -
No Item GSM DCS & PCS
Frequency offset 800kHz
7 Intermodulation attenuation –
Intermodulation product should
be Less than 55dB below the
level of Wanted signal
Power control
Power Tolerance
Power control
Power Tolerance
Level (dBm) (dB) Level (dBm) (dB)
533±3 030±3
631±3 128±3
729±3 226±3
827±3 324±3
925±3 422±3
10 23 ±3 5 20 ±3
8Transmitter Output Power 11 21 ±3 6 18 ±3
12 19 ±3 7 16 ±3
13 17 ±3 8 14 ±3
14 15 ±3 9 12 ±4
15 13 ±3 10 10 ±4
16 11 ±5 11 8 ±4
17 9 ±5 12 6 ±4
18 7 ±5 13 4 ±4
19 5 ±5 14 2 ±5
15 0 ±5
9 Burst timing Mask IN Mask IN
2. PERFORMANCE
- 12 -
2) Transmitter-WCDMA Mode
No Item Specification
1 Maximum Output Power
Class3: +24dBm(+1/-3dB)
Class4: +21dBm(±2dB)
2Frequency Error ±0.1ppm
3 Open Loop Power control in uplink ±9dB@normal, ±12dB@extreme
Adjust output(TPC command)
cmd 1dB 2dB 3dB
+1 +0.5/1.5 +1/3 +1.5/4.5
4 Inner Loop Power control in uplink 0 -0.5/+0.5 -0.5/+0.5 -0.5/+0.5
-1 -0.5/-1.5 -1/-3 -1.5/-4.5
group(10equal command group)
+1 +8/+12 +16/+24
5 Minimum Output Power -50dBm(3.84MHz)
Qin/Qout : PCCH quality levels
6Out-of-synchronization handling of output power Toff@DPCCH/Ior : -22 -> -28dB
Ton@DPCCH/Ior : -24 -> -18dB
7 Transmit OFF Power -56dBm(3.84MHz)
8 Transmit ON/OFF Time Mask
±25us
PRACH,CPCH,uplinlk compressed mode
±25us
9 Change of TFC
Power varies according to the data rate
DTX : DPCH off
(minimize interference between UE)
10 Power setting in uplink compressed ±3dB(after 14slots transmission gap)
11 Occupied Bandwidth(OBW) 5MHz(99%)
-35-15*(∆f-2.5)dBc@∆f=2.5~3.5MHz, 30k
12 Spectrum emission Mask
-35-1*(∆f-3.5)dBc@∆f=3.5~7.5MHz, 1M
-39-10*(∆f-7.5)dBc@∆f=7.5~8.5MHz, 1M
-49 dBc@∆f=8.5~12.5MHz, 1M
2. PERFORMANCE
- 13 -
3)Receiver - GSM Mode
No Item Specification
13 Adjacent Channel Leakage Ratio(ACLR)
33dB@5MHz, ACP>-50dBm
43dB@10MHz, ACP>-50dBm
-36dBm@f=9~150KHz, 1K BW
-36dBm@f=50KHz~30MHz, 10K BW
-36dBm@f=30MHz~1000MHz, 100K BW
14
Spurious Emissions -30dBm@f=1~12.5GHz, 1M BW
(*: additional requirement) (*)-41dBm@f=1893.5~1919.6MHz, 300K
(*)-67dBm@f=925~935MHz, 100K BW
(*)-79dBm@f=935~960MHz, 100K BW
(*)-71dBm@f=1805~1880MHz, 100K BW
15 Transmit Intermodulation
-31dBc@5MHz,Interferer -40dBc
-41dBc@10MHz, Interferer -40dBc
16 Error Vector Magnitude(EVM)
17.5%(>-20dBm)
(@12.2K, 1DPDCH+1DPCCH)
17 Transmit OFF Power
-15dB@SF=4.768Kbps, Multi-code
transmission
No Item GSM DCS & PCS
1
Sensitivity (TCH/FS Class II) -105dBm -105dBm
2
Co-Channel Rejection
C/Ic=7dB Storage -30 ~ +85
(TCH/FS Class II, RBER, TU high/FH)
3 Adjacent Channel 200kHz C/Ia1=-12dB C/Ia1=-12dB
Rejection 400kHz C/Ia2=-44dB C/Ia2=-44dB
Wanted Signal: -98dBm Wanted Signal: -96dBm
4
Intermodulation Rejection 1st interferer: -44dBm 1st interferer: -44dBm
2nd interferer: -45dBm 2nd interferer: -44dBm
5
Blocking Response Wanted Signal: -101dBm Wanted Signal: -101dBm
(TCH/FS Class II, RBER)
Unwanted : Depend on Frequency Unwanted : Depend on Frequency
2. PERFORMANCE
- 14 -
4) Receiver - WCDMA Mode
No Item Specification
1 Reference Sensivitivity Level -106.7dBm(3.84 MHz)
-25dBm(3.84MHz)
2Maximum Input Level -44dBm/3.84MHz(DPCH_Ec)
UE@+20dBm output power(Class3)
3 Adjacent Channel Selectivity(ACS)
33dB
UE@+20dBm output power(Class3)
-56dBm/3.84MHz@10MHz
4In-band Blocking UE@+20dBm output power(Class3)
-44dBm/3.84MHz@15MHz
UE@+20dBm output power(Class3)
-44dBm/3.84MHz@f=2050~2095 and
2185~2230MHz
UE@+20dBm output power(Class3)
-30dBm/3.84MHz@f=2025~2050 and
5 Out-band Blocking 2230~2255MHz
UE@+20dBm output power(Class3)
-15dBm/3.84MHz@f=1~2025 and
2255~12500MHz
UE@+20dBm output power(Class3)
6Spurious Response
-44dBm CW
UE@+20dBm output power(Class3)
-46dBm CW@10MHz
7 Intermodulation Characteristic -46dBm/3.84MHz@20MHz
UE@+20dBm output power(Class3)
-57dBm@f=9KHz~1GHz, 100K BW
8 Spurious Emissions -47dBm@f=1~12.5GHz, 1M BW
-60dBm@f=1920MHz~1980MHz, 3.84M BW
-60dBm@f=2110MHz~2170MHz, 3.84M BW
2. PERFORMANCE
- 15 -
2.4 Current Consumption
(Stand by and Voice Call Test Condition : Bluetooth off, LCD backlight Off)
(VT Test Condition : Speaker off, LCD backlight On)
2.5 RSSI Bar
2.6 Battery Bar
Stand by Voice Call VT
WCDMA
Under 8.5 mA Under 450 mA Under 640mA
(DRX=1.28) (Tx=12dBm) (Tx=12dBm)
Under 6.3 mA Under 380 mA
(Paging=9period) (Tx=Max)
GSM Under 7.0 mA
(@Bluetooth Connected,
Paging=9period)
Level Change WCDMA GSM
BAR 5 → 4 -85 ±2 dBm -85 ±2 dBm
BAR 4 → 3 -90 ±2 dBm -90 ±2 dBm
BAR 3 → 2 -95 ±2 dBm -95 ±2 dBm
BAR 2 →1 -98 ±2 dBm -100 ±2 dBm
BAR 1 → 0-101 ±2 dBm -105 ±2 dBm
Indication Standby
Bar 4 Over 3.83 ±0.05V
Bar 4 → 3 3.82 ±0.05V
Bar 3 → 2 3.74 ±0.05V
Bar 2 → 1 3.67 ±0.05V
Bar 1 → Empty 3.49 ±0.05V
Low Voltage, 3.38 ±0.05V (Stand-by) / 3.49 ±0.05V (Talk)
Warning message+ Blinking [Interval : 3min(Stand-by) / 1min(Talk)]
Power Off 3.28 ±0.05V↓
2. PERFORMANCE
- 16 -
2.7 Sound Pressure Level
No Test Item Specification
1 Sending Loudness Rating (SLR) 8 ±3 dB
2 Receiving Loudness Rating (RLR)
Nor -7 ±3 dB
Max -18 ±3 dB
3 Side Tone Masking Rating (STMR) Min 17 dB
4 Echo Loss (EL) Min 40 dB
5 Sending Distortion (SD) Refer to Table 30.3
6 Receiving Distortion (RD) Refer to Table 30.4
7 Idle Noise-Sending (INS) Max -64 dBm0p
8 Idle Noise-Receiving (INR)
Nor Under -47 dBPA
Max Under -36 dBPA
9 Sending Loudness Rating (SLR) 8±3dB
10 Receiving Loudness Rating (RLR)
Nor -1 ±3 dB
Max -12 ±3 dB
11 Side Tone Masking Rating (STMR) Min 25 dB
12 Echo Loss (EL) Min 40 dB
13 Sending Distortion (SD) Refer to Table 30.3
14 Receiving Distortion (RD) Refer to Table 30.4
15 Idle Noise-Sending (INS) Max -55 dBm0p
16 Idle Noise-Receiving (INR)
Nor Under -45 dBPA
Max Under -40 dBPA
TDMA Noise
-. GSM : Power Level : 5
DCS/PCS : Power Level : 0
17 (Cell Power : -90 ~ -105 dBm)
-,. Acoustic (Max Vol.)
MS/Headset SLR : 8
±
3dB
MS/Headset RLR : -18 ±3dB / -15dB
(SLR/RLR : Mid-value setting)
MS
Headset
MS and
Headset
Max -62 dBm
2. PERFORMANCE
- 17 -
2.8 Charging
• Charging Method : CC & CV (Constant Current and Constant Voltage)
• Maximum Charging Voltage : 4.2 V
• Maximum Charging Current : 600 mA
• Normal Battery Capacity : 1400 mAh
• Charging Time : Max 4.0 hours (except for trickle charging time)
• Full charging indication current (charging icon stop current) : 60 mA
• Cut-off voltage : 3.28 V
3. TECHNICAL BRIEF
- 18 -
3.1 General Description
The U8290 supports UMTS-2100 DS-WCDMA, EGSM-900, DCS-1800, and PCS-1900. All receivers
and the UMTS transmitter use the radioOne1Zero-IF architecture to eliminate intermediate
frequencies, directly converting signals between RF and baseband. The EGSM, DCS1800 and
PCS1900 transmitters use a baseband-to-IF upconversion followed by an offset phase-locked loop
that translates the GMSK-modulated signal to RF.
1
QUALCOMM’s branded chipset that implements a Zero-IF radio architecture.
3. TECHNICAL BRIEF
Figure 3.1-1 Block diagram of RF part
3. TECHNICAL BRIEF
- 19 -
A generic, high-level functional block diagram of U8290 is shown in Figure 1-1. One antenna collects
base station forward link signals and radiates handset reverse link signals. The antenna connects with
receive and transmit paths through a switch module (plus a duplexer for UMTS-2100 operation).
The UMTS receive signal is amplified by the RFL6200 LNA then passes through a bandpass filter
before being applied to the RFR6200 Receiver IC. On-chip circuits downconvert the received signal
directly from RF to baseband using radioOne Zero-IF techniques. Generation of the UMTS
downconverter LO is distributed between the RTR6250 (phase-locked loop), the RFR6200 (buffer
amplifiers and LO distribution circuits) and external UHF VCO and loop filter circuits. The RFR6200 IC
outputs analog baseband signals for further processing by the MSM device. This baseband interface is
shared with the RTR6250 EGSM /DCS/PCS receiver outputs.
EGSM, DCS and PCS receive signals pass through their bandpass filters then are applied to the
RTR6250 IC. Similar to the UMTS path, RTR6250 circuits downconvert the received signals directly
from RF to baseband. The EGSM/DCS/PCS downconverter LO is generated mostly within the
RTR6250 (PLL and distribution functions); the UMTS Rx CH VCO and loop filter are off-chip. The RTR
analog baseband outputs are routed to the MSM6250 IC for further processing (an interface shared
with the RFR).
The UMTS transmit path begins with analog baseband signals from the MSM device that drive the
RTR6250 IC. Integrated PLL and VCO circuits generate the Tx LO used in the quadrature upconverter
that translates baseband signals directly to RF. The RTR6250 output driver stages deliver fairly highlevel signals that are filtered and applied to the power amplifiers (PA). The PA output is routed to the
antenna through a duplexer and switch module.
The shared EGSM-900, DCS-1800, and PCS-1900 transmit path begins with the same baseband
interface from the MSM6250 IC that is used for the UMTS band. A single EGSM/DCS/PCS quadrature
upconverter translates the GMSK-modulated signal to a convenient intermediate frequency (IF) that
forms one input to an offset phase-locked loop (OPLL). OPLL functions are split between the
RTR6250 IC and off-chip loop filter and dual Tx VCO circuits, and translate the GMSK-modulated
signal to the desired EGSM-900, DCS-1800 or PCS-1900 channel frequency. This signal is applied to
a dual power amplifier (only one is active at a time). The enabled path continues with the PA, an
automated power control (APC) circuit that samples the transmit power and adjusts its level, the switch
module (which includes a band-appropriate lowpass filter), and the antenna.
U8290 power supply voltages are managed and regulated by the PM6650 Power Management IC.
This versatile device integrates all wireless handset power management, general housekeeping, and
user interface support functions into a single mixed signal IC. It monitors and controls the external
power source and coordinates battery recharging while maintaining the handset supply voltages using
low dropout, programmable regulators.
3. TECHNICAL BRIEF
- 20 -
The device’s general housekeeping functions include an ADC and analog multiplexer circuit for
monitoring on-chip voltage sources, charging status, and current flow, as well as user-defined off-chip
variables such as temperature, RF output power, and battery ID. Various oscillator, clock, and counter
circuits support IC and higher-level handset functions. Key parameters such as under-voltage lockout
and crystal oscillator signal presence are monitored to protect against detrimental conditions.
3. TECHNICAL BRIEF
- 21 -
3.2 GSM Mode
3.2.1 GSM Receiver
The Dual-mode U8290’s receiver functions are split between the three RFICs as follows:
• UMTS-2100 operation uses the RFL6200 LNA and RFR6200 Receiver ICs to implement the receive
signal path, accepting an RF input and delivering analog baseband outputs (I and Q).
• EGSM-900, DCS-1800, and PCS-1900 modes both use the RTR6250 IC only.
Each mode has independent front-end circuits and down-converters, but they share common
baseband circuits (with only one mode active at a time). All receiver control functions are beginning
with SBI2-controlled parameters.
RF Front end consists of antenna, antenna switch module(SFAY0004601), and three RX saw
filters(GSM, DCS, and PCS). The antenna switch module allows multiple operating bands and modes
to share the same antenna. In U8290, a common antenna connects to one of six paths: 1) UMTS-2100
Rx/Tx, 2) EGSM-900 Rx, 3) EGSM-900 Tx, 4) DCS-1800 Rx, and 5) DCS-1800,PCS-1900 Tx(High
Band Tx’s share the same path), 6) PCS-1900 Rx. UMTS operation requires simultaneous reception
and transmission, so the UMTS Rx/Tx connection is routed to a duplexer that separates receive and
transmit signals. EGSM, DCS, and PCS operation is time division duplexed, so only the receiver or
transmitter is active at any time and a frequency duplexer is not required.
2
The RFIC operating modes and circuit parameters are MSM-controlled through the proprietary 3-line Serial Bus Interface (SBI). The Application
Programming Interface (API) is used to implement SBI commands. The API is documented in AMSS Software - please see applicable AMSS
Software documentation for details.
ANT_SEL2 GPIO(11) ANT_SEL1 GPIO(10) ANT_SEL0 GPIO(9)
GSM 900 TX LOW LOW HIGH
GSM 900 RX/W-CDMA LOW LOW LOW
DCS 1800/PCS 1900 TX HIGH HIGH LOW
DCS 1800 RX LOW HIGH LOW
PCS 1900 RX HIGH LOW LOW
Table 3.2.1-1 Antenna Switch Module Control logic
3. TECHNICAL BRIEF
- 22 -
The EGSM, DCS, and PCS receiver inputs of RTR6250 are connected directly to the transceiver frontend circuits(filters and antenna switch module). EGSM, DCS, and PCS receiver inputs are similar to
the RFR6200 UMTS Rx input in that they also use differential configurations to improve commonmode rejection and second-order non-linearity performance. The balance between the complementary
signals is critical and must be maintained from the RF filter outputs all the way into the IC pins
Since EGSM, DCS, and PCS signals are time-division duplex (the handset can only receive or
transmit at one time), switches are used to separate Rx and Tx signals in place of frequency duplexers
- this is accomplished in the switch module.
The EGSM, DCS, and PCS receive signals are routed to the RTR6250 through band selection filters
and matching networks that transform single-ended 50-Ωsources to differential impedances optimized
for gain and noise figure. Similar to the RFR, the RTR input uses a differential configuration to improve
second-order inter-modulation and common mode rejection performance. The RTR6250 input stages
include MSM-controlled gain adjustments that maximize receiver dynamic range.
The amplifier outputs drive the RF ports of the quadrature RF-to-baseband downconverters. The
downconverted baseband outputs are multiplexed and routed to lowpass filters (one I and one Q)
having passband and stopband characteristics suitable for GMSK processing. These filter circuits
include DC offset corrections.
The filter outputs are buffered and passed on to the MSM6250 IC for further processing (an interface
shared with the RFR6200 UMTS receiver outputs).
3. TECHNICAL BRIEF
- 23 -
Figure 3.2.1-1 RTR6250 IC Functional Block Diagram
3. TECHNICAL BRIEF
- 24 -
3.2.2 GSM Transmitter
The shared GSM Low-band (EGSM900) and High-band (DCS1800, PCS1900) transmit path begins
with the baseband inputs from the MSM6250 IC. These differential analog input signals are buffered,
lowpass filtered, corrected for DC offsets then applied to the GSM quadrature upconverter. The
upconverter LO signals are generated from the transceiver VCO signal by the LO distribution and
generation circuits within RTR6250. This upconverter translates the GMSKmodulated signal to a
convenient intermediate frequency (IF) that forms one input to a frequency/phase detector circuit. This
IF signal is the reference input to an offset phase-locked loop (OPLL) circuit as shown in Figure 3.2.2-1.
The feedback path of this OPLL circuit includes a downconversion from the RF output frequency range
to the IF range. The two inputs to this downconversion mixer are formed as follows:
1. The dual Tx VCO output (operating in the desired RF output frequency range) is buffered within the
RTR6250 IC then applied to the mixer RF port.
2. The LO Generation and Distribution circuits that deliver the transmit path.s LO for the baseband-to-IF
upconversion also provides the .offset LO. signal that is applied to the feedback path.s mixer LO port.
The mixer IF port output is the offset feedback signal - the variable input to the frequency/phase
detector circuit. The detector compares its variable input to its reference input and generates an error
signal that is lowpass filtered by the loop filter and applied to the dual Tx VCO tuning port to force the
VCO output in the direction that minimizes errors. As mentioned earlier, the VCO output is connected to
the feedback path thereby creating a closed-loop control system that will force frequency and phase
errors between the variable and reference inputs to zero.
Figure 3.2.2-1 Offset phase-locked loop interfaces
3. TECHNICAL BRIEF
- 25 -
The waveform at the dual Tx VCO output is the GMSK-modulated signal centered at the desired GSM
channel frequency. A phase-locked loop circuit is used to translate the GMSK-modulated signal from IF
to RF primarily for two reasons:
1. Phase-locked loops provide a lowpass filter function from the reference input to the VCO output. This
results in a bandpass function centered at the desired channel frequency that provides steep, wellcontrolled rejection of the out-of-band spectrum.
2. The resulting output bandpass function is virtually unchanged as the transmitter is tuned over
channels spanning the GSM operating band.
The PA is a key component in any transmitter chain and must complement the rest of the transmitter
precisely. For GSM band operation, the closed-loop transmit power control functions add even more
requirements relative to the UMTS PA. In addition to gain control and switching requirements, the usual
RF parameters such as gain, output power level, several output spectrum requirements, and power
supply current are critical. The gain must be sufficient and variable to deliver the desired transmitter
output power given the VCO output level, the subsequent passive devices’ losses, and the control set
point. The maximum and minimum transmitter output power levels depend upon the operating band
class and mobile station class per the applicable standard. Transmitter timing requirements and inband
and out-of-band emissions, all dominated by the PA, are also specified by the applicable standard.
The active dual Tx VCO output is applied to the dual power amplifier to continue the transmit path, and
feedback to the RTR6250 IC to complete the frequency control loop. The PA operating band (EGSM or
DCS/PCS) is selected by the MSM device GPIO control (GSM_PA_BAND).
3.3 WCDMA Mode
3.3.1 Receiver
The UMTS duplexer receiver output is routed to LNA circuits within the RFL6200 device. These LNA
functions are removed from the RFR6200 IC to improve mixer LO to RF isolation - a critical parameter
in the Zero-IF architecture. Isolation is further improved using high reverse isolation circuits in the LNA
designs. The LNA gain is incrementally and dynamically controlled by the MSM device to maximize
receiver dynamic range.
3. TECHNICAL BRIEF
- 26 -
The UMTS LNA output is routed to the RFR6200 through a band selection filter that transforms a
single-ended 50Ωsource to a differential impedanc e that is matched to the RFR6200 IC. The RFR
input uses a differential configuration to improve second-order inter-modulation and common mode
rejection performance. The RFR6200 input stages include MSM-controlled gain adjustments that further
extend receiver dynamic range.
The RFR6200 IC (Figure 3.3.1-2) provides the UMTS Zero-IF receiver signal path, from RF to analog
baseband. The input gain stage implements MSM controlled gain adjustments to extend receiver
dynamic range. The amplifier output drives the RF port of the quadrature RF-to-baseband
downconverter then the downconverted baseband outputs are routed to lowpass filters (one I and one
Q) whose passband and stopband characteristics are suitable for DS-WCDMA signals. The filter
outputs are buffered and routed to the MSM device for further processing. This baseband interface is
shared with the RTR6250 EGSM/DCS/PCS receiver outputs.
Figure 3.3.1-1 RFL6200 IC functional block diagram
Figure 3.3.1-2 RFR6200 IC functional block diagram
S
B
I
Bias and
Control
Circuits
UMTS_IN UMTS_OUT
VDDA
R_BIAS
GND
UMTS_BIAS
VDDM
SBCK
SBST
SBDT
Ground Slug
GND
GNDGND
RX_IM
RX_IP
ground slug
GND
UMTS_INM
UMTS_INP
RX_QM
RX_QP
TCXOLO_INP LO_INM LO_OUT
Bias
Ckts
R_BIAS
LO Generation
& Distribution
S
B
I
Control
Circuits
VDDM
SBCK
SBST
SBDT
ctls
VDDA
LPF
LPF
Quadrature
Downconverter
3. TECHNICAL BRIEF
- 27 -
The RFR6200 IC includes LO generation and distribution circuitry to reduce offchip component
requirements. The UMTS Rx LO source is created using an external UMTS Rx CH VCO that is closedloop controlled by the RTR6250 PLL2 via a discrete loop filter. The external UMTS_RX_VCO signal is
processed by the LO generation and distribution circuits to create the quadrature downconverter LO
signal. The LO signal applied at the mixer ports are at a frequency different than the VCO frequency.
This assures that the VCO frequency is different than the RF frequency, an important consideration for
Zero-IF processing. QUALCOMM.s Mobile Station Modem (MSM6250) device provides status and
control signaling, employing power reduction features (such as selective circuit power-down, gain
control, and bias control) to extend handset standby time.
3. TECHNICAL BRIEF
- 28 -
3.3.2 Transmitter
The UMTS transmit path begins with analog baseband signals from the MSM device that drive the
RTR6250 IC. The RTR6250 IC provides all the UMTS transmitter active signal-path circuits except the
power amplifiers. Analog (I and Q) differential signals from the MSM device are buffered, filtered, and
applied to Baseband-to-RF quadrature upconverters. Gain control is implemented on-chip.
The RF outputs include an integrated matching inductor, reducing the off-chip matching network to a
single series capacitor.
The RTR6200 UMTS output is routed to its power amplifier through a bandpass filter, and delivers
fairly high-level signals that are filtered and applied to the PA. The PA device used in U8290 is “Load
Insensitive PA”- no need to use isolator - and routed to the duplexer Tx port directly. Transmit power is
delivered from the duplexer to the antenna through the switch module.
The RTR6250 IC integrates LO generation and distribution circuits on-chip, substantially reducing offchip requirements. Various modes and programmable features result in a highly flexible transceiver LO
output that supports not only UMTS transmissions, but all EGSM900 and DCS1800/PCS1900 Rx and
Tx modes as well.
The UMTS Tx LO (PLL1) is generated almost entirely on-chip, requiring only the loop filter off-chip
(two capacitors and two resistors); all UMTS Tx VCO and PLL circuits are on-chip. An internal
RTR6250 switch routes the internal VCO signal to the LO generation and distribution circuits to create
the necessary UMTS Tx LO signals.
3. TECHNICAL BRIEF
- 29 -
3.4 LO Phase-locked Loop
Most LO functions are fully integrated on-chip, do not require user adjustment, and need not be
considered by handset designers. QUALCOMM has established and implemented frequency plans
and LO generation schemes that support the radioOne 6250-IIseries chipset while requiring minimal
off-chip design effort. Only one area requires handset designer attention: the loop filters of each
phase-locked loop (PLL).
3.4.1 UMTS Rx PLL (PLL2)
UMTS Rx LO functional blocks are distributed between the RFR6200 IC, RTR6250 IC, and external
UMTS_RX_CH_VCO and loop filter components (Figure 3.4.1-1).
The external UMTS_RX_CH_VCO must be enabled for UMTS Rx operation and disabled otherwise; a
dedicated MSM6250 IC signal (UHF_VCO_EN ) enables the VCO.
The RFR6200 IC accommodates single-ended or differential LO inputs; if singleended, either pin can
be active. AC-couple the inactive pin to ground using an appropriately valued capacitor (12 pF is used
in U8290). The 27 pF capacitor should be used to AC-couple the active pin to the VCO signal. Using
only the selected VCO signal, the RFR6200 IC LO generation and distribution circuits create the
necessary LO signals for the active quadrature downconverter.
A sample of the downconverter LO is buffered and routed from RFR6200 IC pin 19 to RTR6250 IC pin
32 (RX_VCO_IN). This signal requires a terminating resistor near the RTR6250 IC input pin and an AC
coupling capacitor that assures the internal RTR6250 IC biasing is not disrupted in the example. Good
microstrip or stripline controlled-impedance techniques must be used
Figure 3.4.1-1 UMTS Rx PLL functional block diagram
3. TECHNICAL BRIEF
- 30 -
Most UMTS Rx PLL circuits are included within the RTR6250 IC: reference divider, phase detector,
charge pump, feedback divider, and digital logic that generate LOCK status. The buffered 19.2 MHz
TCXO signal provides the synthesizer input (REF), the frequency reference to which the PLL is phase
and frequency locked.
The reference is divided by the R-Counter to create a fixed frequency input to the phase detector, FR.
The other phase detector input (FV) varies as the loop acquires lock, and is generated by dividing the
RX_VCO_IN frequency using the feedback path.s N-Counter. The closed loop will force FV to equal
FR when locked. If the loop is not locked the error between FV and FR will create an error signal at the
output of the charge pump. This error signal is filtered by the loop filter and applied to the VCO, tuning
the output frequency such that the error is decreased. Ultimately the loop forces the error to approach
zero and the PLL is phase and frequency locked.
Many key PLL performance characteristics are largely determined by the loop filter design - stability,
transitory response, settling time, and phase noise.
3.4.2 Transceiver PLL (PLL1)
All LO functional blocks for the other handset modes(UMTS Tx, EGSM Tx/Rx, DCS Tx/Rx, PCS
Tx/Rx) are integrated into the RTR6250 IC except the loop filter components (Figure 3.4.2-1). On-chip
circuits include reference divider, phase detector, charge pump, VCO, feedback divider, and digital
logic status. The functional description given in Section 3.4.1 for the UMTS Rx PLL applies to the
Transceiver PLL as well.
Figure 3.4.2-1 Transceiver PLL functional block diagram
3. TECHNICAL BRIEF
- 31 -
The off-chip loop filter allows optimization of key PLL performance characteristics (stability, transitory
response, settling time, and phase noise) for different applications. Guidelines are provided in the next
subsection for proper implementation of this critical circuit.
3.5 Off-chip RF Components
3.5.1 Antenna switch module (U207 : LMSP43MA-288)
The antenna switch module allows multiple operating bands and modes to share the same antenna. In
the U8290 design, a common antenna connects to one of six paths: 1) UMTS-2100 Rx/Tx, 2) EGSM
Rx, 3) DCS-1800 Rx, 4) PCS-1900 Rx, 5)EGSM Tx Tx, and 6) DCS-1800, PCS-1900 Tx. UMTS
operation requires simultaneous reception and transmission, so the UMTS Rx/Tx connection is routed
to a duplexer that separates receive and transmit signals. GSM band of operation is time division
duplexed, so only the receiver or transmitter is active at any time and a frequency duplexer is not
required. The module includes lowpass filters for the GSM bands transmit paths to reduce out-of-band
emissions, PA harmonics in particular.
3.5.2 UMTS duplexer (U202 : DMF1950IHC)
A UMTS duplexer splits a single operating band into receive and transmit paths. Important
performance requirements include:
-. Insertion loss . this component is also in the receive and transmit paths; In the U8290 typical losses:
UMTS Tx = 1.2 dB, UMTS Rx = 1.5 dB.
-. Out-of-band rejection or attenuation . the duplexer provides input selectivity for the receiver, output
filtering for the transmitter, and isolation between the two. Rejection levels for both paths are
specified over a number of frequency ranges. Two Tx-to-Rx isolation levels are critical to receiver
performance:
-. Rx-band isolation . the transmitter is specified for out-of-band noise falling into the Rx band. This
noise leaks from the transmit path into the receive path, and must be limited to avoid degrading
receiver sensitivity. The required Rx-band isolation depends on the PA out of-band noise levels and
Rx-band losses between the PA and LNA. Typical duplexer Rx band isolation value is 45 dB.
-. Tx-band isolation . the transmit channel power also leaks into the receiver. In this case, the leakage
is outside the receiver passband but at a relatively high level. It combines with Rx band jammers to
create cross-modulation products that fall inband to desensitize the receiver. The required Tx-band
isolation depends on the PA channel power and Tx-band losses between the PA and LNA. Typical
duplexer Tx-band isolation value is 50 dB.
-. Passband ripple . the loss of this fairly narrowband device is not flat across its passband. Passband
ripple increases the receive or transmit insertion loss at specific frequencies, creating performance
variations across the band.s channels, and should be controlled.
Loading...