SL308 03 Circuit Description

MODEL SL308 VERSION V_0.00 PREPARED BY H/W DATE 17/11/2005

SUBJECT TECHNICAL MANUAL PAGE 1/33

SL308 TECHNICAL MANUAL

Baseband section This document provides a description of the baseband section of the SL308. Most design decisions are explained, but no detailed calculations are included. Total chip solutions(MT6218, MT6305, MT6129) except for RF Power Amplifier(RF3146) are from Media Tek, Taiwan.

I. MT6218 ( GSM/GPRS Baseband Processor )

Figure 1. Block Diagram of MT6218

Figure 1 details the block diagram of MT6218. Based on dual-processor architecture, the major

processor of MT6218 is ARM7EJ-S, which mainly runs high-level GSM/GPRS protocol software as

well as multi-media applications. With the other one is a digital signal processor corresponding for

handling the low-level MODEM as well as advanced audio functions. Except for some mixed-signal

circuitries, the other building blocks in MT6218 are connected to either the microcontroller or the

digital signal processor.




Figure 2. Typical Application of MT6218

1. Micro-Controller Unit Subsystem ARM7EJ-S, plays the role of the major bus master controlling the whole subsystem. Essentially, it

communicates with all the other on-chip modules by way of system buses : AHB Bus and APB Bus.

All bus transactions originate from bus masters, while slaves can only respond requests from bus

masters. Prior to a data transfer can be established, bus master must ask for bus ownership. This is

accomplished by request-grant handshaking protocol between masters and arbiters.

Two levels of bus hierarchy are designed to provide alternatives for different performance

requirements, i.e. AHB Bus and APB Bus for system back bone and peripheral buses, respectively. To

have high performance and proper efficiency, the AHB Bus provides 32-bit data path with multiplex

scheme for bus interconnections.

Only memory addressing method is used in MT6218 based system. All components are mapped onto

MCU 32-bit address space. A Memory Management Unit is employed to have a central decode scheme.

It generates certain selection signals for each memory-addressed modules on AHB Bus.

In order to off-load the processor core, a DMA Controller is designated to act as a master and share the

bus resources on AHB Bus to do fast data movement between modules. This controller comprises

thirteen DMA channels.

A 512KByte SRAM is provided for acting as system memory for high-speed data access. For factory

programming purpose, a Boot ROM module is used. These two modules use the same Internal

Memory Controller to connect to AHB Bus.




External Memory Interface supports both 8-bit and 16-bit devices. Since AHB Bus is 32-bit wide, all

the data transfer will be converted into several 8-bit or 16-bit cycles depending on the data width of

target device. This interface is specific to both synchronous and asynchronous components, like Flash,

SRAM and parallel LCD. This interface supports also page and burst mode type of Flash.

1.1 Processor Core The Micro-Controller Unit Subsystem in MT6218 is built up with a 32-bit RISC core, ARM7EJ-S.

The memory interface of ARM7EJ-S is totally compliant to AMBA based bus system. Basically, it can

be connected to AHB Bus directly.

1.2 Memory Management The processor core of MT6218 supports only memory addressing method for instruction fetch and data

access. It manages a 32-bit address space that has addressing capability up to 4GB. System RAM,

System ROM, Registers, MCU Peripherals and external components are all mapped onto such 32-bit

address space.

1.3 Bus System Two levels of bus hierarchy are employed in constructing the Micro-Controller Unit Subsystem of

MT6218. AHB Bus and APB Bus serve for system backbone and peripheral buses, while an APB

bridge connects these two buses. Both AHB and APB Buses operate at the same clock rate as

processor core.

1.4 Direct Memory Access A generic DMA Controller is placed on Layer2 AHB Bus to support fast data transfers, and also to

off-load the processor. With this controller, specific devices on AHB or APB buses can benefit greatly

from quickly completing data movement from or to memory module, i.e. Internal System RAM or

External SRAM. Such Generic DMA Controller can also be used to connect any two devices other

than memory module as long as they can be addressed in memory space.

1.5 Interrupt Controller Figure 2 outlines the major functionality of the MCU Interrupt Controller. The interrupt controller

processes all interrupt sources coming from external lines and internal MCU peripherals. Since

ARM7EJ-S core supports two levels of interrupt latency, this controller will generate two request

signals : FIQ for fast, low latency interrupt request and IRQ for more general interrupts with lower

priority.




One and only one of the interrupt sources can be assigned to FIQ Controller and have the highest

priority in requesting timing critical service. All the others should share the same IRQ signal by

connecting them to IRQ Controller. The IRQ Controller manages up 32 interrupt lines of IRQ0 to

IRQ31 with fixed priority in descending order.

Figure 3. Block Diagram of the Interrupt Controller

1.6 Internal Memory Controller

System RAM MT6218 provides four 64KByte size of on-chip memory modules acting as System RAM for data

access with zero latency. Such module is composed of four high speed synchronous SRAMs with

AHB Slave Interface connected to system backbone AHB Bus. The synchronous SRAM operates at

the same clock as AHB Bus and is organized as 32-bit wide with 4 byte-write signals capable for byte

operations.

System ROM The System ROM is primarily used to store software program for Factory Programming. However,

due to its advantageous zero latency performance, some of timing critical codes are also placed in this

area. This module is composed of high-speed diffusion ROM with AHB Slave Interface connected to

system backbone AHB Bus.

1.7 External Memory Interface




MT6218 incorporates a powerful and flexible memory controller, External Memory Interface, to

connect with a variety of memory components. This controller provides generic access schemes to

asynchronous/synchronous type of memory devices, such as Flash Memory and SRAM. It can

simultaneously support up to 8 memory banks with max size of 64MB each.

Refer to Figure 2. Typical Application of MT6218.

2. Microcontroller Peripherals MCU Peripherals are devices that are under control of the Microcontroller. Most of them are attached

to the APB of the MCU subsystem, thus shall serve as APB slaves. Each MCU peripheral has to be

accessed as a memory-mapped I/O device, i.e., the MCU or the DMA bus master read or write specific

peripheral by issuing memory-addressed transactions. Refer to Figure2. Typical Application of

MT6218.

2.1 Pulse-Width Modulation Outputs Two generic pulse-width modulators are implemented to generate pulse sequences with programmable

frequency and duty cycle for LCD backlight. The duration of the PWM output signal is Low as long as

the internal counter value is greater than or equals to the threshold value and the waveform is shown in

Figure3.

Figure 4. PWM waveform

PWM1 and PWM2 are devoted to LCM Backlight dimming function and enabling camera flash.

2.2 Alerter The output of Alerter has two sources : one is the enhanced pwm output signal, which is implemented

embedded in Alerter module; the other is PDM signal from DSP domain directly. The enhanced pwm

with three operation modes is implemented to generate a signal with programmable frequency and tone

volume. However the output of Alerter in SL308 is dedicated to the enabling signal of vibrator.

2.3 SIM Interface




The MT6218 contains a dedicated smart card interface to allow the MCU access to the SIM card. It

can operate via 5 terminals, using SIMVCC, SIMSEL, SIMRST, SIMCLK and SIMDATA.

Figure 5. SIM Interface Block Diagram

The SIMVCC is used to control the external voltage supply to the SIM card and SIMSEL determines

the regulated smart card supply voltage. SIMRST is used as the SIM card reset signal. Besides,

SIMDATA and SIMCLK are used for data exchange purpose.

2.4 Keypad Scanner The keypad can be divided into two parts : one is the keypad interface including 7columns and 6

rows ; the other is the key detection block which provides key pressed, key released and de-bounce

mechanism. Each time key pressed or key released, i.e. something different in the 7*6 matrix, the key

detection block will sense it, and it will start to recognize if its a key pressed or key released event.

Whenever the key status changes and is stable, a KEYPAD IRQ will be issued. The MCU can then

read the key pressed directly in registers. And this keypad can detect one or two key-pressed

simultaneously with any combination.

2.5 General Purpose Inputs/Outputs




Figure 6. GPIO Block Diagram

MT-6218 offers 48 general-purpose I/O pins and 3 general-purpose output pins. By setting the control

registers, MCU software can control the direction, the output value and read the input values on these

pins. Besides, these GPIOs and GPOs are multiplexed with other functionalities to reduce the pin

count.

2.6 UART The MT6218 houses three UARTs. The UARTs provide full duplex serial communication channels

between the MT6218 and external devices. However, 1st UART ports (URXD1, UTXD1) are only

available in SL308.

2.7 Real Time Clock The Real Time Clock module provides time and data information. It works on the 32.768KHz

oscillator (OSC100) with independent power supply. When the MS is powered off, a dedicated

regulator is used to supply the RTC block. If the main battery is not present, the backup supply such as

a small mercury cell battery or a large capacitor is used. In addition to provide timing data, alarm

interrupt is generated and it can be used to power up the baseband core through the BBWAKEUP pin.

Also, regulator interrupts corresponding to the seconds, minutes, hours and days can be generated

whenever the time counter value reaches a maximum.

2.8 Auxiliary ADC Unit The auxiliary ADC unit is used to monitor the status of battery and charger, identify the plugged

peripheral, and perform temperature measurement.

ADC0 and ADC1 : current sensing

ADC2 : battery temperature

ADC3 : charging voltage

ADC5 : detecting ear microphone.

2.9 Irda Framer Irda Framer functional block can be divided into twp parts : The transmitting part and the receiving

part. In the transmitter, It will perform BOFs addition, byte stuffing, the addition of 16-bits FCS and

EOF appendence. In the receiving part, it will execute BOFs removal, ESC character removal, CRC

checking and EOF detection. In addition, the framer will pwerform 3/16 modulation and

demodulation to connect to the IR transceiver. The transmitter and receiver all need DMA channel.




Figure 7. Irda Framer Functional Block

3. Microcontroller Coprocessors Microcontroller Coprocessors are designed to run computing-intensive processes in place of MCU.

Those coprocessors intend to offer a solution special for timing critical GSM/GPRS Modem processes

that require fast response and massive data movement. Controls to the coprocessors are all through

memory access by way of APB Bus.

4. Multi-Media Subsystem MT6218 is specially designed to support multi-media terminals. It integrates several hardware

based accelerators such as advanced LCD display controller, hardware JPEG encoder/decoder,

hardware Image Resizer and MPEG4 video CODEC. In addition, MT6218 also incorporates

NAND Flash, USB 1.1 Device and SD/MMC/MS pro controllers for Mass data transfers and

storages.

4.1 LCD Interface A specific LCD controller is implemented to allow MCU to access external LCD module by dedicated

Parallel Interface(NLD00:NLD07) and to improve data throughput for color LCD applications. LCM

is 2.0 inch, 260K colors QCIF and 176x220 resolutions.




Figure 8. LCD Interface Block Diagram

4.2 JPEG Decoder To boost JPEG image processing performance, a hardware block is preferred to aid software and deal

with JPEG file as much as possible. As a result, JPEG Decoder is designed to decode all baseline and

progressive JPEG images with all YUV sampling frequencies combinations.

4.3 JPEG Encoder

The Hardware JPEG Encoder implements the baseline mode of Standard ISO/IEC 10918-1. It

supports YUV422 format for color pictures and greyscale format. For hardware reduction, it uses

stardard DC and AC Juffman tables for both the luminance and chrominance components. To adjust

the picure compression ratio and picture quality, there are 4 levels of quantization that can be

programmed. After initialization by software, the hardware JPEG encoder can generate the entire

compressed file.

4.4 Image Resizer This Block provides image resizing capability. It receives image data from a block-based image

source such as JPEG decoder in format of YUV color space, or a pixel-based image source such as

camera in format of RGB or YUV and performs image resizing. The first pass is coarse resizing pass

and it can shrink the image by a factor of 1, 1/4, 1/16, 1/64. The second pass is fine resizing pass and it

can shrink and enlarge the image in fractional ratio. Refer to the Figrue9 Image resizer block diagram.

The maximum isze of a pixel based source image is only 2047x2047.




Figure 9. Image Resizer Block Diagram

4.5 NAND Flash Interface MT6218 provides 8-bit NAND flash data and 7 interface Signals(NRNB, NCLE, /WP,NALE, /NCE,

/NEW, /NRE). The MCP of SL308 is 128Mbit(Nor Flash)x32MBit(SRAM)+512Mbit(NAND Flash).

Nand Flash interface bus are assigned to LCM data for speed up and high throughput.

4.6 USB Device Controller MT6218 provides a USB function interface that is in compliance with Universal Serial Bus

Specification Rev 1.1. The USB device controller supports only full-speed(12Mbps) operation. The

cellular phone can make use of this widely available USB interfaces to transmit/receive data with USB

host, typically PC.

The USB device uses cable-powered feature for the transceiver but only drains little current. An

external resistor(nominally 1.5kohm) is required to be placed across Vusb and DP Signal. Two

additional external serial resistors mignt be needed to be placed on the output of DP and DM signals to

make the output impedance equivalent to 28~44ohm. Also, USB cable can be used to Charger for 5V

input.

4.7 SD Memory Card Controller The controller fully supports the SD Memory Card bus protocol as defined in SD Memory Card

Specification Part1 Physical Layer Specification version1.0. But SL308 is not interfaced Mini SD

card but T-Flash Memory Card. Interface Signals are same.

The Detection is controlled by INS pin status. When Card is nothing, The INS is high logically. And

When Card inserted, The INS is low.




Figure 10. SD Card Interface Pin Map

5. Audio Front-End The audio front-end essentially comprises voice and audio data paths. The whole voice band data paths

are complied with GSM03.50 specification. Furthermore, Mono hands-free audio or external FM radio

playback path are provided. The stereo audio path facilitates audio quality playback, external FM radio,

and voice playback through headset.

Figure 11. Audio Front-End Block Diagram




Figure 12 shows the block diagram of digital circuits of the audio front-end. The APB register block is

an APB peripheral to get settings from the MCU. The DSP audio port block interfaces with the DSP

for control and data communications. Besides, there is a Digital Audio Interface(DAI) block to

communicate with the System Simulator for FTA or external Bluetooth module for particular

applications. The digital filter block performs filter operations for voice band and audio band signal

processing.

Figure 12. The block diagram of the digital circuits for Audio Front-End

Stereo sound are implemented by TS4990 IC(Mono audio amplifier).

SL308 used 2 in 1 speaker. The AU_Out0_N/_P lines are for Voice Audio. AU_MOUTL was

connected to the Speaker via TS4990 for Ring Tone and Melody(Midi and MP3)

6. Radio Interface Control This Chapter details the MT6218 Interface control with Radio part of a GSM Terminal. Providing a

Comprehensive control scheme, The MT6218 radio interface consists of Baseband Serial

Interface(BSI), Baseband Parallel Interface(BPI), Automatic Power Control(APC) and Automatic

Frequency Control(AFC) together with APC_DAC and AFC_DAC.

6.1 Baseband Serial Interface The Baseband Serial Interface is used to control the external radio components. It utilizes a 3-wire

serial bus to transfer data to RF circuitry for PLL frequency change, reception gain setting, and other

radio control purposes. In this unit, BSI data registers are double-buffered in the same way as the




TDMA event registers. The user writes data into the write buffer and the data is transferred from the

write buffer to the active buffer when TDMA_EVTVAL signal from the TDMA Timer is pulsed.

The Unit supports 2 external components. There are four output pins. BSI_CLK is the output Clock,

BSI_DATA is the serial data port, and BSI_CS0 and BSI_CS1 are the select pins for the 2 components.

BSI_CS1 is multiplexed with other function.

Figure 13. Block diagram of BSI unit.

6.2 Baseband Parallel Interface The Baseband Parallel Interface features a 10-pin output bus used for timing-critical control of the

external circuits. These pins are typically used to control front-end components at the specified time

along the GSM time-base, such as transmit-enable(PA_EN), band switching(BANDSW_DCS), TR-

switch(LB_TX, HB_TX), etc.

Figure 14. Block diagram of BPI Interface




6.3 Automatic Power Control (APC) Unit Automatic Power Control unit is used to control the Power Amplifier module. Through APC unit, we

can set the proper transmit power level of the handset and to ensure that the burst power ramping

requirements are met. In one TDMA frame, up to 7 TDMA events can be enabled to support multi-slot

transmission. In practice, 5 banks of ramp profiles are used in one frame to make up 4 consecutive

transmission slots.

The shape and magnitude of the ramp profiles are configurable to fit ramp-up, intermediate ramp, and

ramp-down profiles. Each bank of the ramp profile consists of 16 8-bit unsigned values, which is

adjustable for different conditions.

The entries from one bank of the ramp profile are partitioned into two parts, with 8 values in each part.

In normal operation, the entries in the left half part are multiplied by a 10-bit left scaling factor, and

the entries in the right half part are multiplied by a 10-bit right scaling factor. Those values are then

truncated to form 16 10-bit intermediate values. Finally the intermediate ramp profile are linearly

interpolated into 32 10-bit values and sequentially used to update to the D/A converter. The block

diagram of the APC unit is shown in Figure 15.

Figure 15. Block diagram of APC unit

The APC Analog Signal is inputted to Power Amplifier Module through Low Pass filter (R202,C221)

6.4 Automatic Frequency Control (AFC) Unit Automatic Frequency Control unit provides the direct control of the oscillator for frequency offset and

Doppler shift compensation. The Block diagram is depicted in Figure 16. It utilizes a 13-bit D/A

converter to achieve high-resolution control. The AFC is always inputted to VCTCXO to gemerated

13Mhz. The Aanlog voltage is about 1.5V and AFC_DAC is about 4200 decimally.




Figure 16. Block diagram of the AFC Controller

7. Baseband Front End

Figure 17. Block Diagram of Baseband Front-End

Baseband Front End is a modem interface between Tx/Rx mixed-signal modules and digital signal

processor. We can divide this block into two parts. The first is the uplink(transmitting) path, which

converts bit-stream from DSP into digital in-phase and quadrature signals for TX mixed-signal module.

The second part is the downlink(receiving) path, which receives digital in-phase and quadrature

signals from RX mixed-signal module, performs FIR filtering and then sends results to DSP. The

uplink path is mainly composed of GMSK Modulator and uplink parts of Baseband Serial Ports, and

the downlink path is mainly composed of RX digital FIR filter and downlink parts of Baseband Serial

Ports. Baseband Serial Ports is a serial interface used to communicate with DSP. In addition, there is a

set of control registers in Baseband Front End that is intended for control of Tx/Rx mixed-signal

modules, inclusive of calibration of DC offset and gain mismatch of downlink analog-to-digital

converters as well as uplink.




7.1 Baseband Serial Ports Baseband Front End communicates with DSP through the sub block of Baseband Serial Ports.

Baseband Serial Ports interfaces with DSP in serial manner. It implies that DSP must be configured

carefully in order to have Baseband Serial Ports cooperate with DSP core correctly.

7.2 Downlink Path ( RX Path) On downlink path, the subblock between RX mixed-signal module and Baseband Serial Ports is RX

Path. It mainly consists of a digital FIR filter, two sets of multiplexing paths for loopback modes,

interface for RX mixed-signal module and interface for Baseband Serial Ports.

Figure 18. Block diagram of Downlink Path

7.3 Uplink Path ( TX Path ) The purpose of the uplink path inside Baseband Front End is to sink TX symbols, one bit for each

symbol, from DSP, then perform GMSK modulation on them, then perform offset cancellation on I/Q

digital signals out of GMSK modulator, and finally control TX mixed-signal module to make D/A

conversion on I/Q signals out of GMSK Modulator with offset cancellation. Accordingly, the uplink

path is composed of uplink parts of Baseband Serial Ports, GSM Encryptor, GMSK Modulator and

Offset Cancellation.




Figure 19. Block Diagram of Uplink Path

8. Timing Generator Timing is the most critical issue in GSM/GPRS applications. The TDMA timer provides a simple

interface for the MCU to program all the timing-related events for receive event control, transmit event

control and the timing adjustment.

In pause mode, the 13MHz reference clock may be switched off temporarily for the purpose of power

saving and the synchronization to the base-station is maintained by using a low power 32.768KHz

crystal oscillator. The 32.768KHz oscillator is not accurate and therefore it should be calibrated prior

to entering pause mode.

Figure 20. The Block Diagram of TDMA Timer.

Figure 21. The Block Diagram of Slow Clocking unit.




9. Power, Clocks and Reset

Figure 22. Major Phone Power States and Operation Modes for MT6218 based terminal

This Chapter descripbes about the power,clock and reset management functions provided by MT6218.

Together with Power Management IC, MT6218 offers both fine and coarse resolutions of power

control by way of software programming. With this efficient method, the developer can turn on

selective resources accordingly in order to achieve optimized power consumption. The Operating

modes of MT6218 as well as main power states provided by the PMIC are shown in Figure 22.

9.1 Baseband to PMIC Serial Interface MT6218 use 3 wires B2PSI interface connected to PMIC, this bi-directional serial bus interface allows

baseband to write command to and read from PMIC. The bus protocol utilizes a 16bits proprietary

format. B2PSICK is the serial bus clock and is driven by the master. B2PSIDAT is the serial data;

master or slave can drive it. B2PSICS is the bus selection signal. Once the B2PSICS goes low,

Baseband starts to transfer the 4 register bits followed by a read/write bit, then wait for 3 clocks for

PMIN B2PSI state machine to decode the Operation for the next succeeding 8 data bits. The State

machine should count for 16 clocks to complete the data transfer.

9.2 Clocks There are two major time bases in the MT6218. For the faster one is the 13MHz clock origination from

an off-chip temperature-compensated voltage controlled oscillator that can be 26MHz. This signal is

the input from the SYSCLK pad then is converted to the square-wave signal. The other time base is the

32.768KHz clock generated by an on-chip oscillator connected to an external crystal.




Figure 23. Clock distributions in the MT6218

9.2.1 32.768Khz Time Base

The 32.768Khz clock is always running. Its mainly used as the time base of the Real Time

Clock(RTC) module, which maintains time and date with counters. In low power mode, the

13Mhz time base is turned off, so the 32.768Khz clock shall be employed to update the critical

TDMA timer and Watchdog timer. This Time base is also used to clock the keypad Scanner

logic. The C180, C182 must be tuned with Oscillator.

9.2.2 13Mhz Time Base

Two 1/2-dividers, one for MCU Clock and the other for DSP Clock, exist to allow usage of

eigher 26 or 13Mhz TXVCXO as clock input. There phase-locked loops(MPLL, DPLL and

UPLL) are used to generate three primary clocks.

MPLL : Provides the MCU System Clock.

DPLL : Provides the DSP System Clock. DPLL can be programmed to provide 1x to 6x

output of the 13Mhz reference.

UPLL : Provides the USB System Clock.

9.3 Reset Management Figure 17 shows reset scheme used in MT6218. There are three kinds of resets in the MT6218, i.e.,

hardware reset, watchdog reset, and software resets.




Figure 24. Reset Scheme used in MT6219

9.3.1 Hardware Reset

This Reset is inputted through the SYSRST# pin frim PMIC(MT6305 Pin 24). The SYSRST# shall be

driven to low during power-on. The Hardware reset has a grlbal effect on the chip. It initializes all

digital and analog circuits except the RTC. Refer to the listed below.

- All Anlog Circuits are turned off

- All PLLs are turned off and bypassed. The 13Mhz system clock is the default time base.

- Special Trap statue in GPIO.

9.3.2 Watchdog Reset

A Watchdog reset is generated when the Watchdog timer expires as the MCU software failed to re-

program the timer counter in time. Hardware blocks that are affected by the watchdog reset are :

- MCU Subsystem

- DSP Subsystem

- External Component (By software program)




9.3.3 Software Reset

These are local reset signals that initialize specific hardware. For example, The MCU or DSP software

may write to software reset trigger registers to reset hardware modules to their initial states, when

hardware failures are detected. The following Modules hae software resets

- DSP Core

- DSP Coprocessors.

II. MT6305 ( GSM Power Management System) The MT6305 is a power management system chip optimized for GSM handsets, especially those based

on the MTK system solution. It contains seven LDOs, one to power each of the critical GSM sub-

blocks. Sophisticated controls are available for power-up during battery charging, keypad interface,

and RTC alarm. The interface Features are listed below.

- Handles all GSM baseband Power management

- 2.8V to 5.5V input range

- Charger input up to 15V

- Seven LDOs Optimized for specific GSM Subsystems

- High Operation Efficiency and Low Stand-by Current

- Li-Ion and NiMH battery Charge function

- SIM Card interface

- Three Open-Drain Output Switches to Control the LED, Alerter and vibrator

- Thermal Overload Protection

- Under Voltage Lock-Out Protecton

- Over Voltage Protecton

- Power on Reset And start up Timer

1. Low Dropout Regulator and Reference The MT6305 integrates seven LDOs that are optimized for their given functions by balancing

quiescent current, dropout voltage, line/load regulation, ripple rejection, and output noise.




Figure 25. Functional Block Diagram of MT6305

2. Digital Core LDO (Vcore)The digital core LDO is a regulator that could source 100mA with 1.2V output voltage with Pin3(DANODE) GND. If Pin2 is not GND, The output Voltage

is 1.8V. It supplies the baseband circuitry in the handset. The LDO is optimized for very low

quiescent current.

3. Digital IO LDO (DVDD) The digital IO LDO is a regulator that could source 100mA with 2.8V output voltage. It supplies the

baseband circuitry in the handset.

4. Analog LDO (AVDD) The analog LDO is a regulator that could source 150mA with 2.8V output voltage. It supplies the

analog sections of the baseband chipsets. The LDO is optimized for low frequency ripple rejection in

order to reject the ripple coming from the RF Power Amplifier burst frequency at 217Hz. The

Decoupling Capacitor C166 must be higher than X5R type.




5. TCXO LDO ( Vtcxo) The TCXO LDO is a regulator that could source 20mA with 2.8V output voltage. It supplies the

temperature compensated crystal oscillator, which needs its own ultra low noise supply and very good

ripple rejection ratio. The Decoupling Capacitor C167 must be higher than X5R type.

6. RTC LDO ( Vrtc) The RTC LDO is a regulator that could source 200uA with 1.2V output voltage with Pin3 GND. If

Pin3 is not GND, The Output Voltage is 1.5V. It charges up a capacitor-type backup coin cell to run

the real-time clock module. The LDO features the reverse current protection.

7. Memory LDO ( Vmem) The memory LDO is a regulator that could source 150mA with 1.8V or 2.8V output voltage selection

based on the supply specs of memory chips. It supplies the memory circuitry in the handset.

8. SIM LDO (Vsim) The SIM LDO is a regulator that could source 20mA with 1.8V or 3.0V output voltage selection based

on the supply specs of subscriber identity modules card. The LDO is controlled independently of the

others LDO.

9. SIM card interface It provides level shifting needs for low voltage GSM controller to communicate with either 1.8V or 3V

SIM cards. In SL308, 3V SIM card is applied. All SIM cards contain a clock input, a reset input, and a

bi-directional data input/output. The clock and reset inputs to SIM cards are level shifted from the

supply of digital IO of baseband chipset to the SIM supply.

Figure 26. Status of Mobile Handset and LDOs.

10. Vibrator , Alerter, LED switches Three built-in open-drain output switches drive the vibrator motor(Pin38), alerter beeper(Pin39) and

LEDs(Pin41) in the handset. Each switch is controlled by baseband chipset with enable pins. The

switch of LED can sink 150mA to drive up to 14 LEDs simultaneously for backlight. The switch of

vibrator can sink 250mA for a vibrator motor. The switch of alerter can sink 300mA to drive the

beeper. And all the open-drain output switches are high impedance when disable.




ALERTER pin is dedicated to Main KEY BackLight LED, VIBRATOR pin is dedicated to Vibrator

Motor.

11. Battery Charger BATUSE pin can set MT6305 to fit the battery type. When BATUSE is set low, Li-ion battery is used.

MT6305 charges the battery in three phases : pre-charging, constant current mode charging, and

constant voltage mode charging. The circuitry of MT6305 combines with a PMOS transistor, diode,

current-sense resistor externally to form a simple and low cost linear charger. MT6305 is available

pulsed top-off charging algorithm by the CHRCNTL pin control from baseband chipset.

Figure 27. Charger and Voltage Detection

Figure 28. Li-Ion Battery Charging Profile.




IV. LRS18C8A (Smart combo RAM + Nor Flash

Memory) and K9F1208U0B( Nand EEPROM) 1. LRS18C8A The LRS18C8A is a mixed multi-chip package containing a 32Mbit smart combo RAM and a 128Mbit

Flash memory. The /BYTE inputs can be used to select the optimal memory configuration. The power

supply for the LRS18C8A can range from 1.7V to 1.95V. The LRS18C8A can perform simultaneous

read/write operations on its flash memory and is available in a 107-pin BGA package making it

suitable for a variety of applications. The Boot block architecture for flash memory is a bottom boot

block. The MCP has two CE# signal for Flash.

These CE# are controlled EA23 address Pin.

Figure 29. MCP Block diagram




2. K9F1208U0B (Nand Flash EEPROM) The K9F1208U0B,offered in 64Mx8Bit or 32Mx16bit, is 512mbit with spare 16MBit capacity. The

device is offered 2.7 ~ 3.3v VCC. Its NAND cell provides the most cost-effective solution for the

solid state mass storage market. A Program operation can be performed in typical 200uS on the

528byte or 264word page and en erase operation can be performed in typical 2ms on a 16kbyte or 8K

word block. Data in the page can be read out at 60ns cycle time per byte. The I/O pins serve as the

ports for address and data input/output as well as command input. The R/B(Pin A6) must be pulled up.

Figure 30. Block Diagram




Figure 31. Array Organization

RF section I. MT6129 (RF Transceiver IC) MT6129 includes LNAs, two RF quadrature mixers, an integrated channel filter, programmable gain

amplifiers(PGA), an IQ demodulator for the receiver, a precision IQ modulator with offset PLL for the

transmitter, two internal TX VCOs, a VCXO, on-chip regulators, and a fully programmable sigma-

delta fractional-N synthesizer with an on-chip RF VCO.




Figure 32. MT6129 Functional block diagram

- Recommended Operating Range Item Symbol Min Typ Max Unit

Power Supply Voltage(VBAT) VBAT 3.1 3.6 3.6 V

Power Supply Voltage(VCCD) VCCD 2.5 2.8 3.1 V

Operating Ambient Temperature Topr -20 25 75 C

1. Receiver The receiver section of MT6120 includes Quad-band low noise amplifiers(LNAs), RF quadrature

mixers, an on-chip channel filter, Programmable Gain Amplifiers(PGAs), quadrature second mixers,




and a final low-pass filter. The very low-IF MT6129 uses image-rejection mixers and filters to

eliminate interference. With accurate RF quadrature signal generation and mixer matching techniques,

the image rejection of the MT6129 can reach 35dB for all bands. Compared to a direct conversion

receiver(DCR), MT6129s very low-IF architecture improves the blocking rejection, AM suppression,

as well as the adjacent channel interference performance.

The ESL808 was designed for Tri-Band(GSM900, DCS1800, PCS1900)

- Receiver Input Frequency Mode Min Max Unit

GSM850 869 894 Mhz

GSM900 925 960 Mhz

DCS 1805 1880 Mhz

PCS 1930 1990 Mhz

2. Transmitter The MT6120 transmitter section consists of two on-chip TX VCOs, buffer amplifiers, a down-

converting mixer, a quadrature modulator, an analog phase detector and a digital phase frequency

detector, each with a charge pump output and on chip loop filter. The dividers and loop filters are used

to achieve the desired IF frequency from the down-conversion mixer and quadrature modulator. For a

given transmission channel, the transmitter will select one of the two different TX reference dividing

numbers. These built-in components, along with an internal voltage controlled oscillator and a loop

filter, implement a translation loop modulator. The TX VCO output is fed to the power amplifier. A

control loop, implemented externally, is used to control the PAs output power level.

- Transceiver Output Frequency Mode Min Max Unit

GSM850 824 849 Mhz

GSM900 880 915 Mhz

DCS 1710 1785 Mhz

PCS 1850 1910 Mhz

3. TX VCO Two power VCOs are integrated with OPLL to form a complete transmitter circuit. The TX VCO

output power is typically 9dBm with +/-2.5dB variation in EGSM bands and +8dBm output power

with +/-2dB variation in DCS1800/PCS1900 bands over extreme Temperature conditions.

The PAM(RF3146) Input range is Typically 3dBm. So 5dB Attenuator is added Between MT6129 and

RF3146. Tx VCO Trequency Range is same with Trasnsceiver Frequency Range.

4. Frequency Synthesizer




The MT6120 includes a frequency synthesizer with a fully integrated RF VCO to generate RX and TX

local oscillator frequencies. The PLL locks the RF VCO to a precision reference frequency at 26MHz.

To reduce the acquisition time or to enable fast settling time for multi-slot data services such as GPRS,

a digital loop along with a fast-acquisition system are implemented in the synthesizer. After the

calibration, a fast-acquisition system is utilized for a period of time to facilitate fast locking.

The frequency ranges of the synthesizer for RX mode are

RX mode GSM850 1737Mhz ~ 1788Mhz

E-GSM900 1850Mhz ~ 1920Mhz

DCS1800 1805Mhz ~ 1880Mhz

PCS1900 1930Mhz ~1990Mhz

The Calculate LO Freqnecy Fvco from RX Channel Frequency Fch is following.

Fvco = 2*Fch-200K for GSM850 and E-GSM900

Fvco = Fch-100K for DCS1800 and PCS1900.

The frequency ranges of the synthesizer for TX mode are

TX mode GSM850 1813Mhz ~ 1868Mhz

E-GSM900 1936Mhz ~ 2059Mhz

DCS1800 1881Mhz ~ 2008Mhz

PCS1900 2035Mhz ~2149Mhz

The Calculate LO Freqnecy Fvco from TX Channel Frequency Fch is following.

(set the divider ratio D1 of TX reference divider = 11)

Fvco = 2*D1*Fch/(D1-1) for GSM850 and E-GSM900

Fvco = D1*Fch/(D1-1) for DCS1800 and PCS1900.

The MT6129 uses a digital calibration technique to reduce the PLL settling time Once the RF

synthesizer is programmed through a 3-wire serial interface, the calibration loop is activated. The main

function of the calibration loop is to preset the RF VCO to the vicinity of the desired frequency

quickly and correctly, thus aiding the PLL to settle faster. On the other hand, since a large portion of

initial frequency error is dealt with by the integrated calibration loop, the overall locking time can be

drastically reduced, irrespective of the desired frequency.

5. Voltage Control Crystal Oscillator(VCXO) VCXO consists of an amplifier, a buffer, and a programmable capacitor array. The VCXO provides the

MT6129 with a selectable reference frequency of either 13MHz or 26MHz. When VCXOFRQ pin is

high, Output Frequency is 26Mhz. When VCXOFRQ pin is low, Output Frequency is 13Mhz.




VCXOFRQ is High in ESL808. The Amplifier is designed to be in series resonance with a standard

26Mhz crysatal. The Crystal is connected from the Input pin XAL of Amplifier to ground through a

series load capacitance. The buffer provides a typical 600mVpp voltage swing. As an alternative, the

reference frequency can ve provided by an external 26Mhz VCTCXO module. When Pin VCXOCXR

is tied to the VCCVCXO supply, the XTAL pin will accept an external signal. Furthermode, the

VCXO control pin can be tied to VCCVCXO to prevent the current leakage during the sleep mode

operation.

6. Regulator The MT6129 internal regulators provide low noise, stable, temperature and process independent

supply voltages to critical blocks in the transceiver. An internal P-channel MOSFET pass transistor is

used to achieve a low dropout voltage of less than 150mV in all regulators.

II. RF3146 ( GSM850,EGSM,DCS and PCS Power

Amplifier Module)

Figure 33. RF3146 Block Diagram

The RF3146 is a high-power, high-efficiency power amplifier module with integrated power control of

RFMD. The device is a self-contained 7mm*7mm*0.9mm lead frame module with 50ohm input and

output terminals. The power control function is also incorporated, eliminating the need for directional

couplers, detector diodes, power control ASICs and other power control circuitry(See figure 34) ; this

allows the module to be driven directly from the DAC output. The device is designed for use as the

final RF amplifier in EGSM900 and DCS handsets. On-board power control provides over 50dB of

control range with an analog voltage input. The RF3146 has Max +35dBm GSM output power and

Max +33dBm DCS output power at 3.5V.




Figure 34. The Shaded area are eliminated on RF3146.

Figure 35. Diagram of the power control

Figure 36. Diagram of the Power control

Most power control systems in GSM sense either forward power or collector/drain current. The

RF3146 does not use a power detector A high-speed control loop is incorporated to regulated the

collector voltage of the amplifier while the stage are held at a constant bias. The Vramp signal is

multiplied by a factor of 2.65 and the collector voltage for the second and third stages are regulated to

the multiplied Vramp voltage. The basic circuit is shown in Figure 24.




III. ESHS-M090SF (Antenna Switch Module

for Tri- Band with SAW Filter) ESHS-M090SF is an Antenna Switch Module for GSM900,DCS1800 and PCS1900 of Hitachi

Metals with Three SAW Modules. Control Pins (VC1, VC2) are connected to LB_TX, HB_TX

(signals from baseband processor). The Control Pins Operating range is 2.4V 2.8V.

Figure 37. The Evaluation board and control logic of ESHS-M090SF

The GSM900 and DCS1800/PCS1900 input port matching impedances are 50 ohm.

The GSM900, DCS1800 and PCS1900(Balance) output port matching impedance are 150ohm.

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