Motorola V100 Service Manual
Level 3 Service Manual
Product Family 38C
Personal Communicator
Model V100
by Toko (toko@gsm-free.org)
3
38C
Level 3 Service Manual Table of Contents
6881036B20
3Table of Contents
Table of Contents
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Product Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Product Names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Product Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Regulatory Agency Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Computer Software Copyrights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
About This Service Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Warranty Service Policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
General Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Operating Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Nonvolatile Memory/Memory Retention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Circuit Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Transceiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Tools and Test Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
GSM Test Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Programming - Software Upgrade and Flexing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Troubleshooting Charts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Part Number Charts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Model Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Identity and Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Related Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Exploded View Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Exploded View Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Index-1
MOTOROLA CONFIDENTIAL - PROPRIETARY
6881036B20 November 20, 2000 i
Table of Contents Product Family 38C
MOTOROLA CONFIDENTIAL - PROPRIETARY
ii November 20, 2000 6881036B20
3
38C
Level 3 Service Manual Introduction
6881036B20
Introduction
Motorola® Inc. maintains a worldwide organization that is dedicated to provide
responsive, full-service customer support. Motorola products are serviced by an
international network of company-operated product care centers as well as authorized independent service firms.
Available on a contract basis, Motorola Inc. offers comprehensive maintenance and
installation programs which enable customers to meet requirements for reliable,
continuous communications. S
Product Identification
Motorola products are identified by the model number on the housing. Use the entire
model number when inquiring about the product. Numbers are also assigned to
chassis and kits. Use these numbers when requesting information or ordering
replacement parts.
Product Names
Product names included in Product Family 38C Personal Communicators are listed
on the front cover. Product names are subject to change without notice. Some
product names, as well as some frequency bands, are available only in certain
markets.
Product Changes
When electrical, mechanical or production changes are incorporated into Motorola
paging products, a revision letter is assigned to the chassis or kit affected, for
example; -A, -B, or -C, and so on.
The chassis or kit number, complete with revision number is imprinted during
production. The revision letter is an integral part of the chassis or kit number and
is also listed on schematic diagrams and printed circuit board layouts.
Regulatory Agency Compliance
This device complies with Part 15 of the FCC Rules. Operation is subject to the
following conditions:
1. This device may not cause any harmful interference, and
2. this device must accept interference received, including interference that may
cause undesired operation.
This class B device also complies with all requirements of the Canadian Interference-Causing Equipment Regulations (ICES-003).
Cet appareil numérique de la classe B respecte toutes les exigences du Règlement
sur le matériel brouilleur du Canada.
MOTOROLA CONFIDENTIAL - PROPRIETARY
6881036B20 November 20, 2000 1
Introduction Product Family 38C
Computer Software Copyrights
The Motorola products described in this manual might include copyrighted Motorola computer software stored in semiconductor memories and other media. Laws in
the United States and other countries preserve for Motorola, Inc. certain exclusive
rights for copyrighted computer programs, including the exclusive right to copy or
reproduce in any form the copyrighted computer software.
Accordingly, any copyrighted Motorola computer software contained in the Motorola products described in this manual cannot be copied or reproduced in any manner
without the express written permission of Motorola, Inc..
Furthermore, neither the purchase of Motorola products nor your receipt of this
manual (whether in connection with a purchase or otherwise) grants, either directly
or by implication, estoppel, or otherwise, any license under the copyrights, patents
or patent applications of Motorola, Inc., except for the normal, nonexclusive,
royalty-free license to use that arises by operation of law in the sale of a product.
Additionally, use of the information in this manual other than in connection with
an associated product purchased from Motorola Inc. requires express written
permission of Motorola, Inc. In this regard, you may not use the information in this
manual to create a software application for separate sale or license to others not in
connection with the associated product purchased from Motorola, Inc.
About This Service Manual
Using this service manual and the many suggestions contained in it assures proper
installation, operation, and maintenance of Product Family 38C Personal
Communicators. Refer any questions about this manual to the nearest Customer
Service Manager.
Audience
This document provides assistance to service personnel in testing and repairing
Product Family 38C Communicators. Service personnel should be familiar with
electronic assembly, testing, and troubleshooting methods, and with the operation
and use of associated test equipment.
Use of this document assures proper installation, operation, and maintenance of
Motorola products and equipment. It contains all service information required for
the equipment described and is current as of the printing date.
Scope
The scope of this document is to provide the reader with basic information relating
to Product Family 38C Personal Communicators, and also to provide procedures
and processes for repairing the units at Level 3 service centers including:
• Unit swap out
• Repairing of mechanical faults
• Basic modular troubleshooting
• Component-level troubleshooting
• Limited PCB component repair requiring unsoldering and soldering
• Testing and verification of unit functionality
• Initiate warranty claims and send faulty modules to Level 4 repair centers.
MOTOROLA CONFIDENTIAL - PROPRIETARY
2 November 20, 2000 6881036B20
Level 3 Service Manual Introduction
Finding Information
A product family is identified by the first three digits of the serial number, unless
covered by an extended warranty. Extended warranty products have two alphabetic
characters in place of the first two digits of the family code. The first digit following
the alphabetic code indicates the number of years the warranty period is in effect.
Conventions
Special characters and typefaces, listed and described below, are used in this
publication to emphasize certain types of information.
➧
G
E
E
Revisions
Any changes that occur after manuals are printed are described in publication
revision bulletins (PMRs). These bulletins provide change information that can
include new parts listing data, schematic diagrams, and printed board layouts.
Warranty Service Policy
Note: Emphasizes additional information pertinent to the subject matter.
Caution: Emphasizes information about actions w hic h may result in equipment
damage.
Warning: Emphasizes information about actions which may result in personal
injury.
Key s to be pressed are represen ted gra phically. For e xample , instead of “Press
the Enter Key”, you will see “Press
Information from a screen is shown in text as similar as possible to what
appears in the display. For example,
Information that you need to type is printed in boldface type
E”.
ALERTS or ALERTS or ALERTS.
The product will be sold with the standard 12 months warranty terms and conditions. Accidental damage, misuse, and extended warranties offered by retailers are
not supported under warranty. Non warranty repairs are available at agreed fixed
repair prices.
Out of Box Failure Policy
The standard out of box failure criteria applies. Customer units that fail very early
on, after the date of sale, are to be returned to Manufacturing for root cause analysis,
to guard against epidemic criteria. Manufacturing to bear the costs of early life
failure.
MOTOROLA CONFIDENTIAL - PROPRIETARY
6881036B20 November 20, 2000 3
Introduction Product Family 38C
Product Support
Customer’s original units will be repaired but not refurbished as standard. Appointed Motorola Service Hubs will perform warranty and non-warranty field service for
level 2 (assemblies) and level 3 (limited PCB component). The Motorola Hi-Tech
Centers will perform level 4 (full component) repairs.
Customer Support
Customer support is available through dedicated Call Centers and in-country help
desks. Product Service training should be arranged through the local Motorola
Support Center.
Ordering Replacement Parts
Only centers authorized to carry out repairs can purchase spare parts. Orders for
spare parts from hubs and Hi-Tech Centers should be placed with the regional
Motorola Parts Distribution Center.
MOTOROLA CONFIDENTIAL - PROPRIETARY
4 November 20, 2000 6881036B20
6881036B20
3
Level 3 Service Manual General Operation
38C
General Operati on
The Product Family 38C Personal Communicator consists of a transceiver and a
microcomputer-controlled decoder, referred to as the controller (see Figure 1).
Messages and calls are received by way of an RF carrier that is frequency modulated
by a coded binary sequence. The circuits in the transceiver board section, through
a triple-conversion process, convert the RF signal to a low frequency signal that is
passed on to the controller. The controller processes the coded data using digital
techniques, and controls messages memory, Liquid Crystal Display (LCD), and alert
tones.
The controller processes coded messages, and forwards the messages to the transmitter. The transmitter section generates a modulated RF carrier signal, amplifies
the signal, then radiates the signal through the antenna.
The following describes the general theory of operation for the Product Family 38C
Personal Communicator. See Figure 1 for a simplified, high-level functional block
diagram. Circuit descriptions are provided. Detailed functional block diagrams and
schematics for the transceiver board and controller are provided in the Supplements
listed in Related Publications.
Antenna
Board
3.6V Li Ion
Battery
Keyboard
RX/TX
Switch
Transceiver
Controller
MAGIC
Whitecap
G CAP
Vibrator
Motor
Display
Backlight
Alert
Transducer
Headset
000700-A
Figure 1. Simplified Functional Block Diagram
MOTOROLA CONFIDENTIAL - PROPRIETARY
6881036B20 November 20, 2000 5
General Operation Product Family 38C
Operating Power
The transceiver board and controller circuit boards obtain power from a 3.6V
rechargable Lithium Ion battery pack which provides initial power to the communicator and charges the internal power source.
There is a danger of explosion if the Lithium Ion battery pack is replaced incorrectly.
Replace only with the same type of battery or equivalent as recommended by the
E
battery manufacturer. Dispose of used batteries according to the manufacturer’s
instructions.
Nonvolatile Memory/Memory Retention
All messages, device status, and setup information stored in FLASH memory are
➧
maintained after removing the primary battery from the device.
To ensure proper memory retention, turn OFF the communicator before removing
the battery. Immediately replace the old battery with a fresh battery.
➧
If the battery is removed while receiving a message, the message will be lost.
MOTOROLA CONFIDENTIAL - PROPRIETARY
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3
38C
Level 3 Service Manual Circuit Description
6881036B20
Circuit Description
Overview
The PF38C Personal Communicator’s hardware is capable of operating in the GSM,
DCS, and PCS bands. One or more bands may be disabled in the software depending
on the country of sale.
Component count has been reduced by use of custom LSI ICs Magic, Whitecap, and
G-Cap II. The Magic IC provides the interface between logic and RF sections. During
receive it drives the RX VCO, demodulates the IF signal and produces base-band
digital data for processing by the logic section. In transmit, it modulates the
transmit data using an internal look up ROM and selects the correct band as well
as controlling the transmit frequency and power level requirements. Whitecap
contains the CPU and interfaces for memory, keypad, display, battery charger,
alarms, and SIM (subscriber identity module) card. The G-Cap II IC provides
voltage regulation, audio, real-time clock, and logic control functionality.
Receive
The RF signal passes from the antenna to an RF switch. The switch is operated by
control voltages that route the signal, depending on whether the receive signal is
GSM or DCS / PCS.
If the signal is GSM, it is routed to a bandpass filter that allows only EGSM signals
through. The filtered input signal is routed to a low noise amplifier having a fixed
gain. The amplified signal is then passed through a second filter that provides
additional selectivity before being fed to the Mixer.
A received PCS signal initially follows the same path as GSM. The output from the
RF switch is filtered to allow only PCS signals to pass, then fed to the PCS switch.
The switch routes the PCS signal to a low noise amplifier. A second provides
additional selectivity before passing to the mixer.
The dual transistor mixer is split between GSM and PCS. Output from the RX VCO
is mixed with the incoming receive signal, resulting in a mixer output consisting of
the sum frequency, difference frequency, and harmonics of the input signal and the
RX VCO. The mixer output passes through a SAW filter which passes only the 400
MHz difference signal.
The RX VCO is a single module Colpitts oscillator capable of operating over three
bands. It is tuned by the charge pump output from the Magic IC. The charge pump
is a steering voltage used to make the oscillator operate at the required frequency.
An isolation amplifier is finely tuned to 400 MHz to amplify the IF and filter
spurious signals from the mixer that passed through the SAW filter. The IF signal
is then passed into the Magic IC for demodulation and generation of the digital
base-band signal.
The 800 MHz local oscillator is the same for all three bands and is controlled by the
Magic IC. It is divided by 2 internally in the Magic IC and used to generate baseband
I and Q signals. These baseband signals are filtered and amplified to provide RxI
and Q. The RxI and Q signals are converted into digital outputs and sent over a
serial bus. The chip will provide for AGC control through the SPI bus.
MOTOROLA CONFIDENTIAL - PROPRIETARY
6881036B20 November 20, 2000 7
Circuit Description Product Family 38C
Transmit
Serial transmit Data is fed into the Magic IC. On the rising edge of DMCS, Magic
IC samples a TX data bit from the SDTX line. An additional TX data bit is sampled
from the SDTX line on every bit clock interval until DMCS goes low. A gated bit
clock is provided at TX_CLK. This clock is inverted from the internal bit clock. Thus,
when TX_CLK transitions from low to high, a new SDTX bit is sent. The Magic IC
reads SDTX on the high to low transition of TX_CLK.
Magic IC contains a look-up ROM to trace out frequency versus time corresponding
to GMSK modulation. The modulator will use the present data bit and the previous
three data bits to set up one of 16 possible waveforms based on the sum of Gaussian
pulses stored in a look up ROM. The resulting signal will then be clocked out at a
16X oversample rate. This data pattern will be input to a four-accumulator fractional N synthesizer with 24-bit resolution.
The charge pump signal is an error voltage supplied from the phase detector
internal to the Magic IC. It is an error voltage and is used to tune the TX VCO to
the transmit frequency. It first passes through the Tx loop Filter. The circuit is
designed to charge a capacitor when TX_EN is initiated to hold the value for the
TX VCO during the burst. Data appears on the TX_CP at the same time DM_CS
occurs. The circuit, is basically a sample and hold circuit, which takes a sample of
the charge pump amplitude voltages and adjusts the charge pump voltage. This
corrected voltage is used to tune the TX VCO to the transmit frequency.
Controller
During power-up, the controller checks for battery presence and measures its
temperature and voltage. Charger presence and type are also sensed, the keypad
and display backlights are turned on, and the 13 MHz clock is started.
The SIM (subscriber identity module) interface is part of the Whitecap IC and
supports both synchronous (prepay card) and asynchronous serial data transmission, as well as both 3V and 5V cards.
The charger is capable of supplying the 400mA of current required to support the
Personal Communicator in standby while, at the same time, charging its internal
battery. Charging current is monitored by the GCAP II. In transmit, the Personal
Communicator requires up to 1.5A to be supplied during each burst. During a TX
pulse the full 400mA from the charger supports B+ in addition to approximately
1.1A from the battery.
Deep sleep mode saves battery life by intermittently shutting off part of the PCB.
Deep sleep mode shutdown is only for a fraction of a second and, during that time,
the GCAP Clock supports the logic side of the unit. This clock, output from GCAP
and fed directly to Whitecap IC, is monitored by Whitecap IC and, should it fail, the
unit is prevented from going into deep sleep mode.
The keypad interface consists of five row and five column pins. The rows are inputs
and the columns can be configured either as inputs or outputs. When operating with
columns as inputs, any active row or column signal will result in an interrupt. The
front keys on the PCB use a three contact design, one of which is tied to ground,
while the other two are pulled high and connected to the row and column inputs.
When a key is pressed all three of its pads are shorted and grounded. Since each
key is uniquely distinguished by the two lines pulled low, no strobing of the keypad
is necessary.
The display is a [64 X 126] pixel graphics display and is connected to the PCB via
a heat seal connector. The antenna PCB is connected to the controller via a flex
MOTOROLA CONFIDENTIAL - PROPRIETARY
8 November 20, 2000 6881036B20
Level 3 Service Manual Circuit Description
connector. The display is made up of glass with polarizers, a display driver and
transflector.
Transceiver
Receive
The RF signal from the base station is received through antenna A1 on the antenna
board to J3 on the transceiver board or from the RF phasing connector TP1. The
signal is fed to Pin 10 or to Pin 3 respectively of RF switch U150. The switch acts
as an isolation between TX and RX. RF switch control is provided by U151 which
determines whether the switch is opened for TX or RX, and if RF is passed to the
Aux RF port or the antenna. RF switching is managed by the following signals:
Table 1. RF Switching Signals
TX_EN RX_EN SW_RF (50W Load) Result
H L Loaded TX through TP1
L H Loaded RX through TP1
H L Not Loaded TX through Antenna
L H Not Loaded RX through Antenna
TX_EN and RX_EN are produced by Whitecap IC U800, Pin C1 and Pin E3
respectively. U151 is supported by the voltages FILTERED -5V (From -5V (U903))
and RF_V1(Q201).
If a receive signal is present (using GSM 900, for example) in the RF switch, and
providing RX275_GSM_PCS (Q2101) is high, the receive signal will be passed to
band pass filter FL400 which will pass the GSM 900 receive frequency.
RX275_GSM_PCS also selects the PCS 1900 frequency passed through FL2400.
The DCS 1800 frequency is selected by RX275_DCS (Q110) and passed through
FL1400
The PCS 1900 and DCS 1800 signals are fed to DCS/PCS select switch U400.
RVCO_PCS and RVCO_DCS (Q1100) then selects the appropriate signal, with
output tuning provided by L1411 and C1411 for DCS and C2411 for PCS.
The selected signal is fed to a low-noise amplifier circuit. Since this circuit is critical
for achieving a very low signal-to-noise ratio, a large amount of external frequency
matching and noise reduction circuitry is employed around the actual amplifiers
Q400 for GSM (supported by RX275_GSM (Q110)) and Q1400 for DCS / PCS
(supported by RX275_DPCS (Q2102)).
The signal is then fed to FL1401 (For GSM 1800 / 1900) or FL401 (For GSM 900)
where harmonics and other unwanted frequencies are removed.
The amplified signal is injected into the base of dual transistor mixer Q450. Both
mixers are supported by RX275 (Q112). The tuned-emitter biasing voltage is
provided by RX275_GSM (Q110) and RX275_DPCS (Q2102).
RX VCO U250 is driven by the Magic IC U200 Pin A1 CP_RX, which is programmed
by the Whitecap IC MQSPI bus. Power is supplied by RVCO_275 (SF_OUT + GPO4
through Q1102).
The generated RX VCO signal is split, with part going back to the Magic IC U200
Pin A3 to serve as the feedback for the RX VCO phase-locked loop. The other part
MOTOROLA CONFIDENTIAL - PROPRIETARY
6881036B20 November 20, 2000 9
Circuit Description Product Family 38C
is amplified through tuned transistor amplifier Q252 before be ing used to mix with
the received frequencies through the emitters of the dual mixer transistor Q450.
The mixer produces sum and difference signals consisting of RX frequency plus RX
VCO frequency and RX frequency minus RX VCO frequency. The difference signal
is fed to SAW (surface acoustic wave) filter FL457. The purpose of the SAW filter
is to provide comprehensive removal of harmonics created during the mixing
process.
The resulting 400 MHz IF signal is passed to isolation amplifier Q480. The isolation
amplifier couples the analog IF signal to the following circuit which has a different
ground and also protects the base-band signals from stray RF. The isolation
amplifier is supported by Magic IC U200 Pin C7 SW_VCC.
Isolation
Amp
MAGIC
IC
U200
Base-band
Signal
101001010100
000714-O
000714-O
Figure 2. IF Isolation Amplifier Operation
The IF signal is then passed to the Magic IC U200 Pin A7 PRE IN where it is
demodulated using external 800 MHz varactor diode CR249 (RX local oscillator set
up), which is driven by from Magic IC U200 Pin A9 LO2_CP.
The demodulated signal is converted internally to base-band digital form and
passed along the RX SPI bus to the Whitecap IC.
The RX SPI signal is made up of BDR (base-band data receive), BFSR (Base-band
Frame Synch Receive) and BCLKR (base-band clock receive), fed from Magic IC
Pin G8, Pin G9, and Pin F7 respectively.
The Whitecap IC U800 receives these signals on Pin A3, Pin D4, and Pin B4.
Within the Whitecap IC the signal is digitally processed to reduce Baud rate and
remove error correction bits.
The resulting digital signal is fed down the DIG_AUD_SPI bus to the GCAP II U900,
where it is converted to analog form and distributed to the correct outputs:
The Alert is generated within the Whitecap IC, given the appropriate data from the
incoming signal or SMS, and is fed to the alert pads LS1. This signal is supported
by ALRT_VCC, which is generated from B+ through Q903.
For the headset only, the SPKR signal is used from GCAP II Pin H6. The output is
fed out to the headset jack J504 Pin 3.
Transmit
Analog voice is fed from the Aux Microphone attached to the headset and is routed
from Pin 1 of the headset jack J504 to GCAP II, Pin H3.
Within the GCAP II, the analog audio is converted to digital and clocked out onto
the DIG_AUD SPI bus to the Whitecap IC U800.
MOTOROLA CONFIDENTIAL - PROPRIETARY
10 November 20, 2000 6881036B20
Level 3 Service Manual Circuit Description
o
All information about the transmission burst is formulated within the Whitecap IC
(timing of the burst, transmit channel, error correction protocol, and in which frame
the information will be carried to the base station). All this information is then
added to the digitized audio and is transferred to the Magic IC U200 along the TX
SPI bus. The bus is made up of BCLKX (base-band clock transmit) Pin B3 and BDX
(base-band data transmit) Pin B6. Since the timing for this data is already decided
for the transmission burst, a frame synch is not required.
The SPI comes into the Magic IC at Pin G7 BCLKX and Pin J2 BDX.
Magic IC operation is very complex. With respect to the transmit path, however, it
integrates Modem, GMSK (Gaussian minimum shift keying), and TIC (translational integrated circuit) functionality.
A very basic block view of how the transmit path works within the Magic IC is shown
in Figure 3.
CLK
BDX
Look
Up
ROM
Digital
representation
of RX VCO
AFC
Channel
Inf
Digital
representation
of TX VCO
F/B
CP_TX
CLK
000715-O
Figure 3. Magic IC Internal Transmit Path
Data is transmitted from Whitecap IC to Magic IC on TX SPI bus BDX. Within the
Magic IC, each bit of data is clocked into a register. The clocked bit, and the three
preceding bits on the register, are then clocked into a look-up ROM which looks at
the digital word and, from that information, downloads the appropriate GSMK
digital representation. Channel information and AFC information from Magic IC
SPI is then added to this new digital word. The resulting word is representative of
the TX IF frequency of GIFSYN products. As in the case of the TIC, the TX frequency
feedback and the RX VCO frequency are mixed to give a difference signal which is
digitally phase-compared with the "modulation" from the look-up ROM. The difference creates a DC error voltage CP_TX that forms part of the TX phase-locked loop.
The error correction voltage CP_TX is then fed from Pin B1 of Magic IC to Pin 4
of the TX VCO IC U350 through the TX loop filter.
The loop filter, made up of U360, Q360, Q361, and C367, smooths out overshoots
in CP_TX when the channel is changed (see Figure 4). If this overshoot were fed to
MOTOROLA CONFIDENTIAL - PROPRIETARY
6881036B20 November 20, 2000 11
Circuit Description Product Family 38C
the TX VCO, the resulting burst would not meet the world standards for GSM with
respect to bandwidth as shown in Figure 5.
Overshoot
Channel 56
Channel 24
000716-O
Figure 4. CP_TX Overshoot
Acceptable
3dB
Bandwidth
Unacceptable
3dB
Bandwidth
000717-O
Figure 5. GSM Bandwidth Standard
The loop filter acts as a very large capacitor and resistor to introduce a long R-C
time for smoothing. It uses a small capacitor and the very high input impedance of
an op amp buffer. During the TX_EN (Whitecap IC Pin C1) period when the
transmitter is preparing to operate, the capacitor charges. On receipt of DM_CS
(Whitecap IC Pin E2), when the Transmitter actually fires, the capacitor discharges
through the op amp giving a smooth TX VCO tuning voltage. The support voltage
for the loop filter is V1_FILT (V2 from GCAP II through Q913 which creates V1_SW.
V1_SW, in turn, creates V1_FILT).
The TX VCO IC produces the required output frequency and is controlled by:
• TX_DCS (TX275 + DCS_SEL through (Q1101)
• TX275_GSM (GSM_SEL + RX275) (Q110)
• TX275_DPCS (GSM_SEL + RX275) (Q2102)
These signals configure the VCO for correct mode of operation (GSM 900 / 1800 /
1900), support voltage being SF_OUT (Magic IC Pin C1).
The TX VCO signal is then fed through buffer amplifier Q330, which is supported
by TX275. The TX VCO signal is split, a sample of the output frequency being
directed back to the Magic IC Pin A3 for use within the TIC part of the Magic IC
to implement the TX phase-locked loop.
Isolation diode CR330 prevents unstabilized TX VCO output from being amplified
and transmitted. CR330 is biased on by the exciter voltage from the PAC IC (power
amplifier control IC) U390 Pin 7 which allows the TX output frequency through to
MOTOROLA CONFIDENTIAL - PROPRIETARY
12 November 20, 2000 6881036B20
Level 3 Service Manual Circuit Description
exciter amplifier Q331 and, at same time, gives more or less drive to the exciter
stage.
The output of Q331 is fed to wide bandwidth PA U300 which is controlled by the
exciter voltage from the PAC IC. U300 is supported by a -ve biasing voltage created
and timed by TX275 (RF_V2 + TX_EN through Q120), filtered -5V (-5V) and DM_CS
(Whitecap IC U800 Pin E2). U300 is also supported by the voltage PA B+ (DM_CS
+ B+ through Q380).
PA matching is controlled with TX_GSM (TX275 + GSM_SEL through Q1101) and
TX_DCS (TX275 + DCS_SEL through Q1101) which switches on or off diodes
CR300 through CR306 to match the PA for GSM or DCS / PCS with the inductive
strips on the PCB.
The amplified signal is then fed to RF switch U150, as discussed in Transceiver:
Receive on Page 9. The amplified signal is either transmitted through antenna A1
or routed to accessory socket RF port J600 Pin 2.
Power Control Operation
The Power Amplifier Control (PAC) IC U390 controls the power output of the
transmitter. Below is a list of the main signals associated with the PAC IC and their
function.
• RF detector RF_IN (U390 Pin 2) provides a DC level proportional to the peak
RF voltage out of the power amplifier. RF_IN is taken via an inductively coupled stripline at the output of the PA.
• DET_SW (U390 Pin 11) controls the variable gain stage connected between
the RF detector and the integrator. When DET_SW is low, stage gain is unity.
When DET_SW is high (floating), the gain is three.
• TX_KEY (U390 Pin 10) pre-charges the exciter and PA. It occurs 20ms before
the start of a transmit pulse.
• EXC (U390 Pin 7) drives the power control port of the exciter. Increasing this
voltage causes the exciter to increase output power.
• SAT_DET (U390 Pin 12). If the feedback signal from the RF detector lags too
far behind the AOC signal this output goes low indicating that the loop is at or
near saturation. SAT_DET signals the DSP to reduce the AOC_DRIVE signal
until SAT_DET rises (see Figure 6).
DMCS
goes high
TX starts
TX_KEY
goes high
SAT_DET
goes low
Linear ramp
down begins
SAT_DET
goes high
Ramp down
ceases
TX_KEY
goes low
DMCS
goes low
000718-O
Figure 6. Saturation Detect Signal Control of PA Drive
MOTOROLA CONFIDENTIAL - PROPRIETARY
6881036B20 November 20, 2000 13
Circuit Description Product Family 38C
• AOC_DRIVE (U390 Pin 8) controls the output power of the transmitter. Under
normal conditions, the control loop will adjust the voltage on EXC so that the
power level presented to the RF detector results in equal voltages present at
INT and AOC. The input level is between 0 and 2.5V.
• ACT (U390 Pin 9). With no RF present, this pin stays high. Once the RF level
increases enough to cause the detector output to rise a few millivolts, this output goes low. ACT is connected to the AOC input through a resister which
causes the transmitter to ramp-up the power until the detector goes active.
Controller
Power-Up sequence
The three power sources available for the PF38C Personal Communicator are:
• Internal battery
• External power via mid-rate charger (Battery must be present to power up)
• External power via fast charger (Battery must be present to power up)
Battery Power Source
The Personal Communicator uses a 3.6V Lithium Ion battery. Power from the
battery is taken from BATT + (battery contacts J604) and routed through battery
FET Q901. Once B+ is available, the unit carries out the following checks.
• Battery temperature is measured to establish whether rapid charge is
required. Table 2 shows voltages appearing at BATT_THERM_AD (J604 Pin 3
and GCAP II Pin B3) for various battery temperatures.
Table 2. Battery Temp vs. BATT_THERM_AD
-40° C 2.75V
25° C 1.39V
40° C 0.96V
• Presence and type of charger is sensed MANTEST_AD (J600 Pin 5 and GCAP
II Pin A1). This is achieved by using different sense resistors within each type
of charger.
Table 3. Charger Type vs. MANTEST_AD
Fast Charger 2.13V
Mid-Rate Charger 1.38V
• Battery voltage is sensed (GCAP II Pin F7 BATTERY).
• Input B+ level is sensed (GCAP II Pin E10 B+).
Charger Power Source
When the charger is connected to accessory plug J600, EXT B+ is available at
Pin 14 and sensed at MOBPORTB (GCAP II U900 Pin D10). Once sensed, the
power is passed through protection diode CR903 and output to EXT B+ FET Q905.
The output is controlled by MIDRATE_1 and power is made available at B+.
Because the charger supports both the Personal Communicator and its internal
battery, the battery is charged at the same time B+ is supplied to operate the unit.
MOTOROLA CONFIDENTIAL - PROPRIETARY
14 November 20, 2000 6881036B20
Level 3 Service Manual Circuit Description
K
The GCAP II is programmed to Boost Mode (5.6V) by PGM0 Pin G7 and PGM1 Pin
G8 both being tied to Ground. Once B+ is applied to GCAP II Pin K5, all the
appropriate voltages to supply the circuit are provided. These are:
• V1 - Programmed to 5.0V. V1 is at 2.775V at immediate power-on, but is
"boosted" to 5.0V through the switch mode power supply L901 / CR902 and
C913. See Figure 7 for basic operation. V1 supplies the DSC bus drivers, negative voltage regulators and Magic IC. V1 is created from GCAP II Pin A6 and
can be measured at C906.
EA
B+ FR
LX
Output
000719-O
Figure 7. V1 Boost Circuit
Basic circuit operation for the boost circuit is as follows: The LX signal (GCAP
II Pin B10) allows a path for B+ to charge the capacitor when the switch is on.
When the switch is off, the capacitor discharges through the inductor setting
up an electric field. The field then collapses setting up back EMF to charge the
capacitor, and so on. The back EMF created by the inductor is greater than B+,
with the +ve half of the cycle passing through the diode to charge a capacitor
that supplies the V_BOOST voltage. The frequency of the switching signal LX
determines the duty cycle of the output wave and therefore the resultant voltage. V_BOOST is fed back into the GCAP.
• V2 - Programmed to 2.775V is available whenever the radio is on and supplies
most of the logic side of the board. V2 is supplied from of GCAP II Pin J2 and
can be measured at either C939 or C941.
• V3 - Programmed to 2.003V to support the Whitecap IC, but does not support
the normal 2.75V logic output from the Whitecap IC. V3 originates from GCAP
II Pin B5 and can be measured at C909 or C910.
• VSIM1 - Used to power either 3V or 5V SIM cards. VSIM1 is dynamically set to
3V upon power up. If, however, the card cannot be read, the SIM card is powered down and attempted to be read at 5V. VSIM1 can be measured at C905
and is distributed from GCAP II Pin C6 (See Controller: SIM Card Interface on
Page 17).
• VREF - Programmed to 2.775V like V2. VREF provides a reference voltage for
the Magic IC and Deep Sleep circuit, is distributed from GCAP II Pin G9, and
can be measured at C919.
• -5V - Used to drive display and generate -10V. The -5V is also used for RF GSM
/ DCS selection signals through U151. Both voltages are derived from V1
through U903 and U904.
• SR_VCC (power cut circuit) - Used to buffer SRAM U702 voltage with a built
in soft reset within the unit's software. SR-VCC protects the user from accidental loss of power for up to 0.5 seconds, as might occur if the unit is dropped,
causing a slight battery contact bounce. SR_VCC allows the unit to appear to
be running normally while, internally, a reset is occurring. During this loss of
power the unit takes its power from RTC BATTERY+ which originates from
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6881036B20 November 20, 2000 15
Circuit Description Product Family 38C
GCAP II Pin D6.
Once a power source has been selected, PWR_SW must be toggled low. This can be
done by pressing power key S500 to create ON_2, which is supported by PWR_SW
(GCAP II Pin C8). ON_2 is also pulled low when an external [fast] charger is
plugged in, providing a battery is present. (See also “Charger Circuit” on page 18.)
The power-up sequence continues as shown in Figure 8.
RESET
EPROM CE
SRAM VB&LB
SPI_CE
R/W
SPI_CE MAGIC
CLK SELECT
VCLK
DSC_EN
50 100 200 300250 350150 400 450
GCAP
BFSR 1.7 after RESET, BCKLR at 1.6s
5000
DOWNLINK
V1
UPLINK
000720-O
Figure 8. Power-up Sequence Timing Diagram
On initial power up, all the keypad backlights (DS500 - DS509 and DS512 - DS522)
and display backlights (DS504 - DS510 on the antenna board in flip housing) are
turned on. They are supported by the signal ALRT_VCC (B+ through Q903) and
switched by BKLT_EN (Whitecap IC Pin K3) through Q907.
MOTOROLA CONFIDENTIAL - PROPRIETARY
16 November 20, 2000 6881036B20
Level 3 Service Manual Circuit Description
13 MHz clock. Initially, upon power being applied to the Magic IC, crystal Y200
(supported by CRYSTAL_BASE (Magic IC Pin E1)) emits a 26 MHz signal to the
Magic IC. The 26 MHz signal is internally divided by two, to produce the external
13MHz clock. The 13 MHz clock is then fed out of the Magic IC on Pin J6 Magic
IC_13MHz and distributed to Whitecap IC Pin H10 CLKIN, then from Whitecap
IC Pin B7 to GCAP II Pin F5 as GCAP_CLK. At the same time, 13 MHz varactor
Diode CR248 is producing an output. This output is controlled in the following way:
The 26 MHz from Y200 is divided down to 200 kHz and fed to a phase comparator
within the Magic IC. The 13 MHz from CR248 is also divided down and fed to the
phase comparator, the difference in phase producing an error voltage that is fed
onto the cathode of varactor CR248 to stabilize the 13 MHz clock. Once the software
is running and the logic side of the board has successfully powered-up, the
CLK_SELECT signal from Whitecap IC Pin A1 is fed to Magic IC Pin G6. This in
turn switches the Multiplexer from the output of Y200 to the output of CR248 (see
Figure 9).
Phase 1
Y200
26MHz
F
F
2
Phase 2
F
F
130
13MHz Output
200
Multiplexer
to White
PLL
kHz
cap
Phase
Detector
Erro r Vo ltage
F
F
65
CR248
13MHz
MAGIC IC
U913
000721-O
Figure 9. 13 MHz Clock Block Diagram
SIM Card Interface
The SIM interface is part of the Whitecap IC U800 and supports both synchronous
(prepay card) and asynchronous serial data transmission. The SIM card is interrogated on power-up. VSIM1 (SIM_VCC) defaults to 3V but, if a 5V card is present
the SIM card is powered-down and VSIM1 reprogrammed to 5V. SIM inputs and
outputs are level-shifted within GCAP II U900 to 3V. These signals are:
• Reset. Whitecap IC Pin E9 RST0 to GCAP II Pin K7 LS1_IN_TG1A. This sig-
nal is level-shifted to the required voltage and fed to SIM contacts J803 Pin 2
from Pin J7 LS1_OUT_TG1A.
• Clock. This is a 3.25MHz signal from Whitecap IC Pin E9 CLK0 [Pin E7] to
GCAP II Pin G6 LS2_IN. This signal is level-shifted to the required voltage
and fed out to SIM Contacts J803 Pin 1 from Pin F6 LS2_OUT.
• SIM I/O. Data transmission to and from SIM card.
• TX: From SIM card contact SIM I/O J803 Pin 6 through to GCAP II Pin
J8 SIM I/O. Level-shifted to desired voltage and out through Pin K10
MOTOROLA CONFIDENTIAL - PROPRIETARY
6881036B20 November 20, 2000 17
Circuit Description Product Family 38C
LS3_TX_PA_B+ to Whitecap IC Pin F3 DAT0_TX.
• RX: Data from Whitecap IC Pin B5 DATA0_RX to GCAP II Pin H8
LS3_RX where the signal is level-shifted to desired voltage and output
on Pin J8 SIM I/O to SIM contacts J803 Pin 6 SIM I/O.
• SIM_PD. From BATT_THERM battery contact. With no batteries present, the
unit will not power-up. If batteries are present, but colder than -15° C and no
card is inserted, the output of the comparator Q905 stays high and the unit
displays INSERT CARD. When the battery temperature is above -15° C
(BATT_THERM voltage approximately 2.51V), but the SIM card is either not
inserted or faulty, CHECK CARD displays.
Charger Circuit
Either the mid-rate charger or the full rate charger may be used. (See also “Charger
Power Source” on page 14.)
In standby, Q905 is opened to provide the approximately 50mA required by the
PF38C Personal Communicator circuitry. Q900 also opens, controlled by CHRGC
(GCAP II Pin E8) to provide a charge of 350mA to the battery. The charger is
capable of supplying the 400mA of current required to support the Personal
Communicator in standby while, at the same time, charging its internal battery.
Charging current is monitored at GCAP II Pin D9 I_SENSE by monitoring the
voltage drop across current sense resistor R913.
In standby, MIDRATE_1 = 0 and MIDRATE_2 = 0
Figure 10. Standby Operation Battery Charging
000722-O
MOTOROLA CONFIDENTIAL - PROPRIETARY
18 November 20, 2000 6881036B20
Level 3 Service Manual Circuit Description
Tx burst
I supply = I radio B+ + I chrg
400mA = 50mA + 350mA
Current
TX Background
I Tx burst = I supply + I batt contrib
1.5A = 400mA + 1.1A
.
000723-O
Figure 11. Transmit Operation Battery Charging
In TX background mode the Communicator requires the same current as in standby
mode, with 50mA supporting the unit and 350mA charging the battery. During TX
background, however, the EXT B+ FET Q905 is switched off causing the charger
current to be directed through the charging FET Q900.
In TX background, MIDRATE_1 = 0 and MIDRATE_2 = 1
During transmission, the communicator requires up to 1.5A to be supplied during
each burst. During a TX pulse the full 400mA from the charger supports B+ in
addition to approximately 1.1A from the battery.
In TX burst, MIDRATE_1 = 1 and MIDRATE_2 = 1
Deep Sleep Mode
Deep sleep mode saves battery life by intermittently shutting off part of the PCB
as follows: STBY_DL is generated from Whitecap IC Pin F1, through a standby
delay circuit consisting of diode CR912 and logic gate U906 which provides a short
delay between activation of STBY_PC5 and STBY_DL. This is a hardware patch
for timing issues related to the Whitecap IC's deep sleep module (DSM). The
resulting signal is passed onto Q911 and Q912 which, in turn:
• Grounds VREF, making Magic IC inoperable.
• Grounds V2, switching off Magic IC, Front END IC and inhibits the Transmit
path through RF_V2.
Deep sleep mode shutdown is only for a fraction of a second and, during that time,
the GCAP Clock supports the logic side of the unit. The GCAP clock is generated
MOTOROLA CONFIDENTIAL - PROPRIETARY
6881036B20 November 20, 2000 19
Circuit Description Product Family 38C
by Y900, which generates a 32.768 MHz clock. This clock is output from GCAP Pin
C7 and fed directly to Whitecap IC Pin P4. The clock is always monitored by
Whitecap IC and should it fail, the unit is prevented from going into deep sleep
mode.
Keypad Interface
The keypad interface consists of five row and five column pins. The rows are inputs
and the columns can be configured either as inputs or outputs by setting bit 5 of
the COL_CONTROL register (1 = input, 0 = output).
When operating with columns as inputs, any active row or column signal will result
in an interrupt. The active state (high or low) for columns and rows can be selected
by setting bit 2 of the COL_CONTROL and ROW_CONTROL respectively.
In this product, the keys are active low. (The front keys and the PCB artwork keys
use a three contact design.) One of the contacts is tied to ground while the other
two are connected to the row and column inputs. When a key is pressed all three of
its pads are shorted and therefore grounded. Each key is uniquely distinguished by
the two lines pulled low. No strobing of the keypad is necessary.
Table 4. Keypad Mapping
Function Key KBR0 KBR1 KBR2 KBR3 KBR4 KBC0 KBC1 KBC2 KBC3 KBC4
AS5090 0
BS5080 0
CS5070 0
DS5060 0
ES5050 0
FS5040 0
GS5030 0
HS5020 0
IS50100
JS517 0 0
KS515 0 0
LS515 0 0
MS514 0 0
NS513 0 0
OS512 0 0
PS511 0 0
QS510 00
RS524 0 0
SS523 0 0
TS522 0 0
US521 0 0
VS520 0 0
WS519 0 0
XS518 00
YS530 0 0
MOTOROLA CONFIDENTIAL - PROPRIETARY
20 November 20, 2000 6881036B20
Level 3 Service Manual Circuit Description
Table 4. Keypad Mapping (Continued)
Function Key KBR0 KBR1 KBR2 KBR3 KBR4 KBC0 KBC1 KBC2 KBC3 KBC4
ZS529 0 0
Comma S528 0 0
Period S527 0 0
?S526 0 0
ALT S525 0 0
Colon S534 0 0
Shift S533 0 0
Fast Access S548 0 0
Smart S532 0 0
Voice Notes S531 0 0
Left S538 0 0
Right S537 0 0
Up S536 0 0
Down S535 0 0
Menu S541 0 0
Space S539 0 0
Ok/Enter S540.S545 0 0
Mail S543 0 0
Cancel S542 0 0
Editor S547 00
Display
The display is a [64 X 126] pixel graphics display and is connected to the PCB via
a 27 Pin ZIF connector J902. The display is made up of glass with polarizers, a
display driver and transflector. It is [connected to the antenna PCB through a heat
seal connector. The LCD is controlled by:
• CS1 Chip Select which originates from DP_EN_L, Whitecap IC Pin A11
to J902 Pin 1.
• RES which originates from RESET, Whitecap IC Pin P2 to J902 Pin 2.
• R/W which originates from R_W, Whitecap IC Pin B11 to J902 Pin 4.
• 8 Data Lines from Whitecap IC DO - D7
• The display is supported by V2 and -10V (originating from U904 and can
be measured on C965)
• The data/command signal AO from Whitecap IC Pin B12.
Vibrator
Vibrator M1 is reflowed to the bottom side of the Controller board. The vibrator is
controlled by the signal VIB_EN Whitecap IC Pin K1 and B+ through U501.
MOTOROLA CONFIDENTIAL - PROPRIETARY
6881036B20 November 20, 2000 21
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