Motorola A1000 Service Manual
3G A1000 TRAINING AID
1
Introduction:
It is the intent of this document to be used as a supplemental guide with the 3G training classes.
The information contained within this document is based on initial designs and theory of
functionality of 3G A1000 transceivers. It is also important to note that circuit designs are expected
to change in the future and certain information within this document will no longer be valid. All
information here in is subject to change and subsequent revisions of this document will be updated
as new design changes occur.
Future revisions of this document will elaborate further on efficient troubleshooting techniques.
Any questions, comments about this guide can be emailed to:
jerrypainter@motorola.com
June 3, 2004
Revision 1.0
MOTOROLA CONFIDENTIAL PROPRIETARY
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WCDMA Rx
Ceramic
Bandpass Filter
1
2
3
4
EGSM Rx
1805-1880
MHz
925-960
MHz
DCS Rx
1930-1990
MHz
PCS Rx
Antenna Switch
Diplexing
Networks
Balun/Matching
Networks
Harmonic
Filters
V1
ANT
RF
Gnd
WCDMA Tx
Ceramic
Bandpass
Filter
WCDMA Rx
Notch Filter
WCDMA Tx DCS/PCS Tx
EGSM Tx
EGSM Tx
DCS/PCS Tx
WCDMA Tx
GSM Rx
SAW Filters
DCS Rx
PCS Rx
EGSM Rx
TL3 TL4
TL5
TL1
TL2
FL6
FL1
FL7
FL2
FL3
FL4
FL8
FL9
FL10
FL11
FL12
FL13
FL14
V2
V3
V4
UMTS
WCDMA
LNA
GSM 1800
LNA
GSM 1900
LNA
GSM 900
LNA
GSM 900
PA
GSM 1800 /
GSM 1900
PA
WCDMA
2100
PA
TL6
TL7
TL0
WCDMA RX
The WCDMA Rx (downlink) frequency band is 2.11 - 2.17GHz and sensitivity @ ~106dBm.
FL1 Front End Module Part # 4889729N01
Overview:
The A1000 Front End Module (FEM) integrates a four position antenna switch controlled by
Harmony (U100), logic decoding and level shifting, diplexers, transmit harmonic filters, SAW
(Surface Acoustic Waveform) filters and matching components on a multi-layer ceramic module.
The module provides band selection and filtering between the EGSM, DCS, PCS and WCDMA
receive and transmit bands- to a single antenna port. The diplexing arrangement permits reception
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3G A1000 TRAINING AID
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of WCDMA signals in any switch position. This allows the phone, while in a GSM call in any band,
to detect signals from a WCDMA base station. The decision may then be made to hand over to the
WCDMA system. Similarly, EGSM base station signals can be detected while the phone is in a
WCDMA call to permit a handover decision from WCDMA to EGSM (This is not possible for base
station signals in the DCS and PCS bands.).
WCDMA Rx:
Signals received at the antenna between 2110 – 2170 MHz will see any path through the RF
switch as an open circuit due to the characteristics of FL1 through FL4. Consequently WCDMA Rx
signals will go through WCDMA Rx band-pass filter FL6 to the WCDMA receiver. Due to the outof-band impedance of FL6 and the phase rotation provided by TL2 and impedances inside the
Front End Module, signals in the other bands will see FL6 as an open circuit, preventing them from
reaching the WCDMA receiver.
WCDMA Tx:
Signals from the WCDMA transmitter pass through WCDMA Tx Band-pass Filter FL7, then through
diplexing network FL1, which isolates them from the EGSM Rx SAW filter while allowing them to
pass to the antenna when the switch is in position 1.
EGSM Rx:
With the switch in position 1, signals arriving at the antenna in the EGSM Rx band pass through
diplexing network FL1 to EGSM Rx SAW FL11. FL1 also provides attenuation at WCDMA Tx
frequencies to protect the SAW from transmit power. To a lesser degree, it also provides isolation
from transmit power when the switch is in position 3 (DCS/PCS Tx) and position 4 (EGSM Tx), as
the switch isolation alone may be insufficient to protect the SAW filter
PCS Rx:
With the switch in position 2, signals arriving at the antenna in the PCS Rx band pass through FL3
to PCS Rx SAW FL10. This position of the switch is not diplexed with a transmit path, so the
network may be simpler than the others. Like the other GSM receive paths, however, sufficient
attenuation at the other transmit frequencies is needed to protect the SAW from transmit power
unless the switch isolation is adequate.
DCS / PCS Tx:
When the switch is in position 3, signals from the DCS/PCS transmitter pass through Notch Filter
FL8 and diplexing network FL2 to the antenna port. The Tx harmonic filter is shown separately for
clarity, but the required harmonic attenuation would typically be provided by the stopband
characteristic of FL2. Notch filter FL8 attenuates thermal noise in the WCDMA Rx band coming
from the DCS/PCS transmitter, and forms a part of the overall diplexing network along with the
phase shift provided by TL4.
EGSM Tx:
Signals from the EGSM transmitter pass through diplexer FL4, which protects the DCS Rx SAW
filter from transmit power while allowing the EGSM Tx signal to pass to the antenna when the
switch is in position 4. The EGSM Tx harmonic filter is shown separately for clarity, but this
MOTOROLA CONFIDENTIAL PROPRIETARY
3G A1000 TRAINING AID
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function would typically be provided by the stopband characteristic of FL4. TL5 represents the
transmission line length between the EGSM transmit coupler/detector and the EGSM Tx pin on the
Front End Module.
DCS Rx:
With the switch in position 4, signals arriving at the antenna in the DCS receive band pass through
diplexer FL4 to DCS Rx SAW FL9. FL4 also provides attenuation to protect the SAW from EGSM
transmit power, which shares the same switch position.
WCDMA RX
(Freq 2110-2170MHz)
U30 LNA Part # 5109944C61
The first IC in the WCDMA Rx line up is U30 (MC13820), which is a Low Noise Amplifier. The RX
frequency will be amplified and passed on to OneLife WB through FL300. The LNA is conrolled by
Harmony (U100) through two enable lines. MBC_EN1 enables gain for the LNA while MBC_EN2
enables the IC. Both lines can be probed at testpoints located near Harmony (TP120 and TP121).
U30 operates from the PCAP supply voltage VRF_RX_2_775.
U300 ONELife WB Part # 5109923D59
The ONElife WB is combination down converter/mixer and demodulator. VCO frequencies are
provided by PRIMSYN IC by control from Harmony. Control and programming are done through a
SPI interface from Harmony. Two supplies are required to power the IC, VRF_DIG_1.875V for SPI
lines and VRF_2.775V for RF portions.
Programming checks of the IC can be done by probing VCC_SF on C301 and C306. If this voltage
is not present ONELife is not operating. Testpoints are also available for AGC stages located near
Harmony (U100). These are TP 122-126.
MOTOROLA CONFIDENTIAL PROPRIETARY
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OneLife
WCDMA
WCD
LN
Mix
Mix1-IFIF1-PMOutp
Buff
Bi-2-Bi-
2-
C_mo
BB
Tracking
Mix
Tracking
PM
AGC
Trk_C
(15.36M
AG
VC
/
/
Syn_F
Syn_F
VCO_Tu
Jon
Jan 13,
Analog
Analog
Analog
Analog
DCOC_
DCOC_
DCOC_
DCOC_
I2+Q2-Compar
SOS
SOS
RF
2110-
SOS
90de
MOTOROLA CONFIDENTIAL PROPRIETARY
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