Service Manuals, User Guides, Schematic Diagrams or docs for : . Rare and Ancient Equipment Ericsson Mobile Phones ERICSSON EF738 TechDes
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Technical Description
Ericsson Mobile Phone EF738
Technical Description
2
Technical Description
Contents
Overview __________________________________________ 7
Basic Building Blocks ______________________________________ 8
Transceiver Block Diagram _________________________________ 9
PCB ____________________________________________________ 10
Mechanical Design __________________________________11
Man Machine Interface (MMI)_______________________ 12
Keypad _________________________________________________ 12
Display _________________________________________________ 12
Acoustic Signals __________________________________________ 12
Top LED Indicator _______________________________________ 12
Radio Design ______________________________________ 13
General Overview ________________________________________ 13
Antenna Connector ___________________________________________ 13
Antenna Filters ______________________________________________ 13
Receiver Part________________________________________________ 14
Receiver Front End ________________________________________ 14
IF Part __________________________________________________ 14
Receiver Back-End ________________________________________ 15
Synthesizer _________________________________________________ 16
Programming _____________________________________________ 16
Power___________________________________________________ 16
Lock Detect ______________________________________________ 16
VCTCXO __________________________________________________ 17
Transmitter _________________________________________________ 18
TX Blocks _______________________________________________ 18
MALIN ____________________________________________________ 19
TX-IF VCO ______________________________________________ 19
TX Mixer ________________________________________________ 19
TX Modulation ___________________________________________ 19
TX-IF Frequency Control ___________________________________ 19
Programmable Prescaler ____________________________________ 19
Power and Charging Design _________________________ 20
Regulators ______________________________________________ 20
Reset ___________________________________________________ 21
On/Off Control __________________________________________ 21
Charging Circuitry _______________________________________ 21
Transient/ESD Protection__________________________________ 22
Off Current Draw ________________________________________ 22
User Interface _____________________________________ 23
Illumination _____________________________________________ 23
Buzzer __________________________________________________ 23
LCD Display_____________________________________________ 23
Keypad _________________________________________________ 23
Continued on next page
3
Technical Description
Logic Design ______________________________________ 24
GUSTAV ________________________________________________24
Circuit Description ___________________________________________ 24
6303 ____________________________________________________ 24
ROM ___________________________________________________ 24
RAM ___________________________________________________ 24
Bus Interface _____________________________________________ 24
Decoder _________________________________________________ 25
Serial Interface____________________________________________ 25
External Ports_____________________________________________ 25
WatchDog On/Off _________________________________________ 25
IFC _____________________________________________________ 25
BAR ____________________________________________________ 25
Clock Generator___________________________________________ 25
Internal Ports _____________________________________________ 26
Modem __________________________________________________ 26
Baud Clock ______________________________________________ 26
I2C Controller ____________________________________________ 26
FLASH EPROM __________________________________________26
EEPROM ________________________________________________26
Audio Design ______________________________________ 27
Receive Audio Circuit Description ___________________________27
Receive Audio Interface _______________________________________ 27
De-Emphasis Network ________________________________________ 27
RXSENSE Programmable Gain Stage ____________________________ 27
Receive Bandpass Filter _______________________________________ 27
Expandor Gain ______________________________________________ 28
RX HF Attenuation ___________________________________________ 28
RX Volume Control __________________________________________ 28
EARSENS Programmable Gain Stage ____________________________ 28
Externally Programmable Gain Stage_____________________________ 28
Earpiece Driver ______________________________________________ 29
AFMS _____________________________________________________ 29
Transmit Audio Circuit Description __________________________29
ATMS _____________________________________________________ 29
Microphone Input ____________________________________________ 29
Soft Limit __________________________________________________ 30
INPSENSE Programmable Gain Stage____________________________ 30
Transmit Bandpass Filter ______________________________________ 30
TX HF Attenuator ____________________________________________ 30
Compressor _________________________________________________ 30
Pre-emphasis ________________________________________________ 30
Hard Limit__________________________________________________ 31
Transmit Lowpass Filter _______________________________________ 31
AUDIODEV Programmable Gain Stage __________________________ 31
Summing Amplifier __________________________________________ 31
TXSENSE Programmable Gain Stage ____________________________ 31
Low Voltage Detect Circuit _________________________________31
Continued on next page
4
Technical Description
RX and TX Sat Circuits ___________________________________ 32
RX SAT Filter ______________________________________________ 32
RX SAT Schmit Trigger_______________________________________ 32
TX SAT Filter_______________________________________________ 32
TX SATDEV Programmable Gain Stage __________________________ 32
8Kbit/s Manchester Data Circuit ____________________________ 32
Data Filter __________________________________________________ 32
DATADEV Programmable Gain Stage ___________________________ 32
HandsFree Circuit ________________________________________ 32
Software Design ___________________________________ 33
Power Down Control______________________________________ 33
Timing and Operation_____________________________________ 33
Main Modes of Operation______________________________________ 33
Power Saving Sleep Function___________________________________ 33
Software Assignments _____________________________________ 33
Technical Specifications _____________________________ 34
General ____________________________________________________ 34
Transmitter _________________________________________________ 34
Receiver ___________________________________________________ 34
5
Technical Description
6
Technical Description
Overview
The Ericsson EF738 Mobile Phone is a small, lightweight phone operating at 3.8V.
It is a class 4 cellular telephone that is fully compatible with the ETACS system
with extended frequencies.
The EF738 includes the following three exterior parts:
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