LG MG200 User manual

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M MG200
Service Manual
MG200
P/N : MMBD0047701 (1.0) Date : April 2005
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The information in this manual is subject to change without notice and should not be construed as a
commitment by LGE Inc. Furthermore, LGE Inc. reserves the right, without notice, to make changes to
equipment design as advances in engineering and manufacturing methods warrant.
This manual provides the information necessary to install, program, operate and maintain the MG200.
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Table Of Contents
1. Introduction ....................................... 4
1.1 Purpose ................................................... 4
1.2 Regulatory Information ............................ 4
1.3 Abbreviation .............................................6
2. General Performance ....................... 7
2.1 Product Name ....................................…..7
2.2 Supporting Standard ................................7
2.3 Main Parts ............................................... 7
2.4 H/W Feature ............................................ 8
2.5 S/W Features .........................................10
3. H/W Circuit Description ..................13
3.1 General Description ...............................13
3.2 Receiver Part .........................................13
3.3 Transmiter Part ...................................... 16
3.4 Digital Baseband(DBB)
Processor .............................................. 20
3.5 Analog Baseband(ABB)
Processor .............................................. 24
3.6 Camera Circuit .......................................42
4. TROUBLE SHOOTING .................... 46
4.1 Main Components Placement
(MG200) ................................................ 46
4.2 FPCB Components Placcement ............47
4.3 Baseband Components .........................47
4.4 Main Components ................................. 47
4.5 Power On Trouble ................................. 49
4.6 Charging Trouble ...................................50
4.7 LCD Display Trouble ............................. 52
4.8 Receiver Trouble ................................... 54
4.9 Microphone Trouble ...............................59
4.10 Vibrator Trouble ................................... 62
4.11 Keypad Backlight Trouble .................... 64
4.12 Folder Open/Close Trouble ................. 66
4.13 SIM Detect Trouble ..............................68
4.14 Earphone Trouble ................................ 70
4.15 Camera Trouble ...................................75
5. DOWNLOAD .................................... 91
5.1 Download Setup .................................... 91
5.2 Download Procedure .............................92
6. SERVICE AND CALIBRATION ........99
6.1 Service S/W ...........................................99
6.2 Calibration ........................................... 102
7. CIRCUIT DAIGRAM ....................... 107
7.1 BB ........................................................107
7.2 AUDIO/MIDI ....................................... 108
7.3 MMI ......................................................109
7.4 CAMERA/SIM/VIB ............................... 110
7.5 LCD I/F .................................................111
7.6 RE RITA............................................... 112
8. PCB LAYOUT ................................. 113
9. ENGINEERING MODE ................... 115
10. STANDALONE TEST ................... 116
10.1 Setting Method ...................................116
11. EXPLODED VIEW &
REPLACEMENT PART LIST ........117
11.1 EXPLODED VIEW ............................. 117
11.2 REPLACEMENT PARTS
<Mechanic component> ................... 119
11.2 REPLACEMENT PARTS
<Main component> ................... 122
11.3 ACCESSORY ................... 133
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1. INTRODUCTION
- 4 -
1. INTRODUCTION
1.1 Purpose
This manual provides the information necessary to repair, calibration, description and download the
features of the MG200
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 you’re 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 config uring the equipment to prevent unauthorized use. LGE
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.
LGE 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
ca using 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 MG200 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 MG200 must be performed only by the LGE 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.
E. Notice of Radiated Emissions
The MG200 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.
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1. INTRODUCTION
- 5 -
F. Pictures
The pictures in this manual are for illustrative purposes only; your actual hardware may look slightly
different.
G. Interference and Attenuation
An MG200 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
systemboards.
•When repairs are made to a system board, they should spread thefloor 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.
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1. INTRODUCTION
- 6 -
1.3 Abbreviations
For the purposes of this manual, following abbreviations apply:
APC Automatic Power Control
BB Baseband
BER Bit Error Ratio
CC-CV Cons tant Current – Constant Voltage
DAC Digital to AnalogConverter
DCS Digital Communication System
dBm dB relative to 1 milliwat t
DSP Digital Signal Processing
EEPROM Electrical Erasable Programmable Read-Only Memory
EL Electroluminescence
ESD Electrostatic Discharge
FPCB Flex ible Printed Circuit Board
GMSK Gaussian Minimum Shift Keying
GPIB General Purpose Interface Bus
GSM Global System for Mobile Communications
IPUI International Portable User Identity
IF Intermediate Frequency
LCD Liquid Crystal Display
LDO Low Drop Output
LED LightEmitting Diode
OPLL Offset Phase Locked Loop
PAM Power Amplifier Module
PCB Printed Circuit Board
PGA Programmable GainAmpli
fi er
PLL Phase Locked Loop
PSTN Public Switched Telephone Net work
RF Radio Frequency
RLR Receiving Loudness Rating
RMS Root Mean Square
RTC Real Time Clock
SAW Surface Acoustic Wave
SIM Subscriber Identity Module
SLR Sending Loudness Rating
SRAM Static RandomAccess Memory
STMR Side Tone Masking Rating
TA Travel Adapter
TDD Time Division Duplex
TDMA Time Division Multiple Access
UART Universal Asynchronous Receiver/Transmitter
VCO Voltage Controlled Oscillator
VCTCXO Voltage Control Temperature Compensated Crystal Oscillator
WAP Wireless Application Protocol
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2. GENERAL PERFORMANCE
- 7 -
2. General Performance
2.1 Supporting Standard
MG200 : Support GPRS (Class 10)
2.2 Supporting Standard
Supporting Standard GSM 850/PCS 1900 Dual-Band
with seamless handover
Phase 2+ (include AMR)
SIM Toolkit : Class 1, 2, 3, A~E
GSM 850 TX : 824 - 849 MHz
GSM 850 RX : 824 - 849 MHz
PCS1900 TX : 824 - 849 MHz
PCS 1900 RX : 824 - 849 MHz
WAP 2.0
JAVA 2.0
MMS
IM : WV 1.1
Frequency Range
ItemFeatureComment
Application Standard
Calypso - AMR C035(PD751992GHH)
IOTA(TWL3025)
RITA / TRF6151C PG2.4
Digital Baseband
Analog Baseband
RF Chip
2.3 Main Parts : GSM Solution
For the purposes of this manual, following abbreviations apply:
Supporting Standard GSM 850/PCS 1900 Dual-Band
with seamless handover
Phase 2+ (include AMR)
SIM Toolkit : Class 1, 2, 3, A~E
GSM 850 TX : 824 - 849 MHz
GSM 850 RX : 824 - 849 MHz
PCS1900 TX : 824 - 849 MHz
PCS 1900 RX : 824 - 849 MHz
WAP 2.0
JAVA 2.0
MMS
IM : WV 1.1
Frequency Range
ItemFeatureComment
Application Standard
Calypso - AMR C035(PD751992GHH)
IOTA(TWL3025)
RITA / TRF6151C PG2.4
Digital Baseband
Analog Baseband
RF Chip
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2. GENERAL PERFORMANCE
- 8 -
One button access
Item
Form Factor
Battery
Size
2) Packing Type :Inner Pack
1) Capacity Standard :
Li-lon, Min 1000mAh (SANYO)
Dual Folder
Sub LCD Icon
Alphanumeric Key
Function Key
Side Key
Total # of Keys
: 12
: 12
: 3
: 27
Function Key :
4 Key Navigation, OK,
F1, F2, SND, END/PWR,
CLR, Camera, Gallery
Weight
Volume
PCB
Status Indicator
Keypad
Stand by time
Charging time
Talk time
RX sensitivity
TX output power
GPRS compatibility
SIMcardtype
Display
Built -in Camera
Feature Comment
Standard :
88.8 x 46 x 24.3mm
96.5g
DRX6
At GSM 850MHz PL 5
Class4 (GSM)
Class1 (PCS)
Size :
34.15 (W) x 53.55(H) x 5.7(T) [mm]
One PCB : 8 Layers, 1t
82.8cc
3 hr.
Min : 3.3 hr.
GSM 850 : -105 dBm
PCS 1900 : -105 dBm
GSM 850 : 33 dBm
PCS 1900 : 30 dBm
GPRS Class 10
Plug-In SIM
3V
Main LCD
128*160, 65K Color STN(1.77”)
Backlight : White LED
Sub LCD
96 x 64 Mono
330K CMOS Camera (VGA)
More than 200 hr.
2.4 H/W Features
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2. GENERAL PERFORMANCE
- 9 -
Item
ANT
System connector
PC synchronization
3 Pole (2.5mm)
24 Pin
Fixed Type
Memory
Speech coding
Data & Fax
Ear Phone Jack
Vibrator
IrDA
MIDI (for Buzzer
Function)
Voice Recording
Speaker Phone
Travel Adapter
CDROM
Options
Feature Comment
Yes
Flash : 128Mbit
SRAM : 64Mbit
Buzzer Function By Using Speaker
Phone & MIDI IC
Built in Data & Fax support
FR, EFR, HR, AMR
NO
YAMAHA 40 Poly
Yes
Yes
Yes
TBD
Ear-Microphone
Handsfree Car Kit
Simple Handsfree Kit
Cigarette Lighter Adapter
Data Cable
Built in Vibrator
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2. GENERAL PERFORMANCE
- 10 -
Item
RSSI
Battery Charging
Key Volume
0 ~ 5 Levels
0 ~ 4 Levels
0 ~ 5 Level
1 ~ 5 Level
Audio Volume
Time / Data Display
Multi-Language
Service Dial
Number
Own Number
Voice Memo
Quick Access
Mode
Speed Dial
CLIP / CLIR
Phone Book
Last Dial Number
Last Missed
Number
Last Received
Number
Search by Number
/ Name
Group
Fixed Dial Number
FeatureComment
Yes
Yes
Phone Book / Web Access /
Sound / Message / IM / Camera /
Gallery / Voice Dial
English / Spanish / France
Voice mail center - > 1 key
Tot al 255 Member
Possible Rename
NITZ
Yes (Different Melody)
Yes (2~9)
Yes (20)
Yes (20)
Yes (10)
Yes
Yes
Yes
Yes
Name only
7
3 Number + 1 Memo + 1 E-mail
+ Group Select + Picture
2.5 S/W Features
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2. GENERAL PERFORMANCE
- 11 -
Over WAP
Item
Call Reminder
Network Selection
Mute
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
WAP 2.0
Operator Dependent
Call Divert
Call Barring
Call Charge (AoC)
Fax & Data
Wall Paper
Call Duration
SMS (EMS)
E - Mail
SMS Over GPRS
Game
Calendar
Memo
World Clock
Unit Convert
Download Melody /
Wallpaper
SIM Lock
WAP Browser
FeatureComment
Automat IC / Manual
EMS : Release 4 (Except Text Align)
Over SMS
Open wave 6.2
Default 4ea
Yes
Yes
1
Yes
Yes
20
Length / Surface / Volume / Weight
100
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2. GENERAL PERFORMANCE
- 12 -
Item
SIM Toolkit
MMS
EONS
Class 1, 2, 3, A - E
Yes
Yes
Yes
Yes
Yes
Yes
CPHS
Camera
JAVA
Voice Dial
IrDA
GPRS
Hold / Retrieve
Conference Call
DTMF
Memo pad
TTY
AMR
Feature Comment
Open wave MMS Client
V4.2
Internal / 300 KB
CLDC V1. 1 / MIDP V 2.0
Download Over WAP
10
Class 10
Max. 6
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
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3. H/W CIRCUIT DESCRIPTION
- 13 -
3. H/W Circuit Description
3.1 General Description
The RF part consists of a transmitter, a receiver, a synthesizer, a voltage supply and a VCTCXO part.
And the main RF Chipset TRF6151C [U607] is a single-chip triple-band transceiver for the extended
global system for mobile communication [GSM850MHz] /Digital communication system [PCS1900MHz]
voice and data transfer applications. This device integrated direct conversion receive architecture, a
transmitter based on a modulation loop architecture and fractional-N synthesizer part with built in
TXVCO and Local-VCO.
3.2 Receiver Part
The Receiver part in TRF6151C [U607] contains all active circuits completely, full receiver chain with
the exception of discrete front-end RF SAW filters. The filtered and amplified signal is down converted
in the RF-mixer to the base-band output. The receive path is supported by inter nal channel filtering.
Figure 1. RF Receiver Block
FL601
Antenna Switch
GSM850
U607/TRF6151C
LNA
D
I
P
PCS
PCS
DCS
GSM
PGA
Q
I
:2 / :4
N div.
R div.
X601
VC-TCXO
26MHz
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3. H/W CIRCUIT DESCRIPTION
- 14 -
3.2.1 RF Front End
Antenna switch and dual saw filters are integrated in FEM (FL601). The Received RF signals
(GSM 869MHz ~ 894MHz, PCS 1930MHz ~ 1990MHz) are fed into the antenna and Mobile switch.
An antenna matching circuit is between the antenna and the mobile switch. The Antenna Switch in
FEM (FL601) is used to control the Rx and Tx paths. And, the input signals VC1, VC2 and VC3 of
FEM are directly connected to base-band controller to switch either Tx or Rx path on. FEM (FL601)
supports for dualFEM control logics given below Table 2.1 The receiver part uses a direct
conversion receiver architecture that allows for the on-chip integration of the DC offset
compensation system, eliminating DC offset from the demodulated signal.
Switch Mode VC1
H
HH
H
LL
L
L
LL
L
L
VC2 VC3
GSM850 Tx
PCS1900 Tx
GSM850 Rx
PCS1900 Rx
Table 3-1. The Logic and Current
The TRF6151C integrates dual differential input LNAs that are matched to the 100 ohm in GSM850
and 100 ohm in PCS balanced-output SAW filters through external LC matching networks.
3.2.2 Demodulator and Baseband Processing
In direct conversion receiver there is only one mixer down-converting received RF signal to BB
signal directly. TRF6151C has 4 Gain steps. Front end and VGA high gain mode is 66dB, Front-
end intermediate Gain and VGA high gain mode is 60dB, Front-end low gain and VGA high gain
mode is 46dB, Front-end and VGA low gain mode is 20dB. The Rx gain setting is done in the AGC
algorithm. The nominal gain of the receiver is set as a function of the expected signal strength at
the antenna input so that a desired level is reached at the Rx I/Q. The receiver chain in TRF6151C
has variable gain parts, LNA, Mixer, LPF, VGA, VGA Filter, Auxiliary gain control and VGA. The
gain settings can be adjustable via 3-wire bus control lines. The base-band signals pass via
integrated low-pass filters to the base-band A/D converters. The remainder of the channel filtering
is performed by the baseband chipset. The demodulator contains switches to maintain the sense
of the baseband I/Q outputs with respect to the incoming RF signal on GSM850 and PCS1900.
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3. H/W CIRCUIT DESCRIPTION
- 15 -
3.2.3 Synthesizer
The RF main chipset includes a fully integrated VCO with an on-chip LC tank. A fractional-N
synthesizer can phase lock the local oscillator used in both transmit and receive path to a precision
frequency reference input. The fractional-N operation offers low phase noise and fast setting times,
allowing for multiple slot applications such as GPRS. The counter and mode settings of the
synthesizer are also programmed via 3-wire interface.
Figure 2. Block diagram of Synthesizer Part
90o
M
divider
R
divider
26 MHz
MAIN PLL
PFD
N (=B*P + A)
divider
Programmable
MAIN loop filter
MAIN VCO 2
@ 3.80 GHz
MAIN VCO 1
@ 3.37 GHz
PFD
PAD
toward RX mixers
TX LB VCO
= TX GSM 850 / TX GSM 900
TX HB VCO
= TX DCS 1800 / TX PCS 1900
LO
L
divider
TX GSM 850 [824.2~837.0 MHz]===> MAINVCO2, L=4, M=26, R=55, N=8242~8370, TXLBVCO
TX GSM 850 [837.2~848.8 MHz]===> MAINVCO2, L=4, M=52, R=30, N=4186~4244, TXLBVCO
TX GSM 900 [880.2~914.8 MHz]===> MAINVCO1, L=4, M=52, R=35, N=4401~4574, TXLBVCO
TX DCS 1800 [1710.2~1784.8 MHz]===> MAINVCO1, L=2, M=26, R=70, N=8551~8924, TXHBVCO
TX PCS 1900 [1850.2~1909.8 MHz]===> MAINVCO1, L=2, M=26, R=70, N=9251~9549, TXHBVCO
TX GSM 850 [869.2~893.8 MHz]===> MAINVCO1, L=4, R=65, N=8692~8938
TX GSM 900 [925.2~959.8 MHz]===> MAINVCO2, L=4, R=65, N=9252~9598
TX DCS 1800 [1805.2~1879.8 MHz]===> MAINVCO2, L=2, R=65, N=9026~9399
TX PCS 1900 [1930.2~1989.8 MHz]===> MAINVCO2, L=2, R=65, N=9651~9949
toward PAs
I
O
IF Programmable IF filter
(62.8 MHz ~ 152.2 MHz)
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3. H/W CIRCUIT DESCRIPTION
- 16 -
3.3 Transmitter Part
The Transmitter part contains OPLL parts of RF Main Chipset [TRF6151, U607], Power Amplifier
Module [SKY77325, U604] and Front-End Module [ESHS-L080SF, FL601]. The transmit section of RF
Main Chipset [TRF6151C, U607] consists of an I/Q base-band up-converter, an offset phase-locked
loop [OPLL]. The RF GMSK outputs from the transmit VCO are fed directly to the RF power amplifier
modules.The peak output power and the profile of the transmitted burst are controlled by means of
incorporated power control circuits inside of PA and DAC output from the Baseband Controller. The PA
outputs pass to the antenna connector via Front-End Module [ESHS-L080SF, FL601].
Figure 3. FEM Block diagram
XTAL
Tank
Serial
Interface
M DIV
R DIV
Phase
Comp.
Phase
Comp.
N DIVIDER :2/:4
3.6 GHz
PAD
GSM850 / GSM900 Quad Band PA
GSM1800 / GSM1900
I
Q
I
Q
26 MHz
90
PAD
Voltage
Regulators
PA
Controller
LNA850
/ LNA900
LNA1800
LNA1900
Quad Band
FEM
3.3.1 IF Modulator
The Baseband Converter (BBC) within the Analog Baseband Chipset [TWL3014, U101] generates
I/Q baseband signals for the transmit vector modulator. The Tx-modulator implements a
quadrature modulator. A quadrature mixer up-converts the differential baseband I/Q signals with
the IFLO to generate a IF signal, which signal is filtered and used as the reference input to the
OPLL. The IFLO is divided by two to generate the quadrature LO signals for the quadrature
modulator.
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3. H/W CIRCUIT DESCRIPTION
- 17 -
Figure 4. Block diagram of if Modulator
26 MHz
Serial
Interface
XTAL
I
Q
M DIV
90
3.3.2 OPLL
The OPLL consists of a feedback mixer, a phase detector, a loop filter, and a fully integrated
TXVCO.
The TXVCO is centered between the DCS 1800 and PCS 1900 bands, and its output is divided by
2 for the GSM 850 and E-GSM 900 bands. The RFLO frequency is generated between 1272 and
1483 MHz. To allow a single VCO to be used for the RFLO, high-side injection is used for the GSM
850 and E-GSM 900 bands, and low-side injection is used for the DCS 1800 and PCS 1900
bands. Low-pass filters before the OPLL phase detector reduce the harmonic content of the
quadrature modulator and feedback mixer outputs. The cutoff frequency of the filters is
programmable with the FIF[3:0] bits in register 04h. The OPLL requires no external duplexer to
attenuate transmitter noise and spurious signals in the receive band. Additionally, the output of the
transmit VCO (TXVCO) is a constant-envelope signal which reduces the problem of spectral
spreading caused by non-linearity in the PA.
Figure 5. Block diagram of OPLL
XTAL
Serial
Interface
M DIV
R DIV
Phase
Comp.
Phase
Comp.
N DIVIDER :2/:4
3.6 GHz
PAD
GSM850/ GSM900
GSM1800 / GSM1900
I
Q
26 MHz
90
PAD
Voltage
Regulators
PA
Controller
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3. H/W CIRCUIT DESCRIPTION
- 18 -
3.3.3 Power Amplifier
The Power Amplifier Module [SKY77325, U604] is a dual-band GSM/PCS power amplifier module
that incorporates an indirect closed loop method of power control. The indirect closed loop is fully
self-contained and it does not require loop optimization. It can be driven directly from the DAC
output in the baseband circuit. On-board power control provides over 37 dB of control range with
an analog voltage input [VAPC]. Efficiency is about 49% at GSM850 and about 53% at PCS.
V BATT
I reg OUT Vcc1 Vcc2
DCS/PCS IN
47 pF CMOS Power
Controller IC
DCS/PCS
Output
Match DCS / PCS OUT
GSM OUT
Output
Match
iPAC
Module
GSM
GaSa
Power
Amplifier
50 k
PAC Enable
Band Select
GSM IN
V
APC
75 m
50 k
Figure 6. Internal Functional Block diagram
m
B
d5
.3
:T
T
A
mBd
5.3
:T
T
A
01
6C
u
33
p
9
3
5
16C
22 VAPC 20 VBATT
3VCC1A
VCC1B
8
VSENSE
19
T
U
O
_
S
C
P
_SCD
7
1
7
GND1 9 GND2 GND3 10
11
GND4 GND5 13
14
GND6 16 GND7 18 GND8 GND9 21
N
I
_
MS
G621 TU
O_
MS
G
NC
1
2
E
LB
A
N
E
_C
A
P
PGND23
D
V
SR
51
5
23
7
7
YKS
4
0
6
U
S
B4
5
N
I_
S
C
P
_
S
C
D
p21
4
1
6C 8
06C
p33
5
06C
A
N50
6R
0
22
21
6
C
H
n
8
1
u
1
0.0
0
16
L4
0
6
C
A
N
A
N
1
1
6C
6
06
C
u10.0
2
6
6
C
p21
2
0
6
R
022
30
6R
0
22
406
R
81
3
1
6C
u
10
.0
606R
0
2
2
1
06R
8
1
2
0
6C
p9.3
3
6
6
C
p
74
DNA
B
_
A
P
C
PA
N
O_AP
Figure 7. Schematic of PAM circuit
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3. H/W CIRCUIT DESCRIPTION
- 19 -
3.3.4 26MHz Clock
Figure 8. Schematic of VCTCXO circuit
APC
X601
26MHz
RF2.85V
TCXO
VCC ONG
C667
1000p
R617
15K
OUT VCONT 1
2
3
4
C656
2.2u
C654
1000p
APC
RF2.85V
C660
1000p
C655
0.01u
U605
MIC5255-2.85BM5
C559
1u
(1608)
C658
1u
(1608)
VBAT
IN
GNO
EN
OUT
BYP
1
2
3
4
5
3.3.5 Power Supplies and Control Signals
An external LDO [U605] is used to provide DC power to VCTCXO [X601], Buffer [U605] which is
used for buffering FEM control signals from DBB and the RF Main Chip [TRF6151C, U607].
Figure 8. Schematic of VCTCXO circuit
APC
X601
26MHz
RF2.85V
TCXO
VCC ONG
C667
1000p
R617
15K
OUT VCONT 1
2
3
4
C656
2.2u
C654
1000p
APC
RF2.85V
C660
1000p
C655
0.01u
U605
MIC5255-2.85BM5
C559
1u
(1608)
C658
1u
(1608)
VBAT
IN
GNO
EN
OUT
BYP
1
2
3
4
5
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