System Overview - LG GB160 Service Manual

3.1.1 System Overview

MT6223D is an entry level chipset solution with class 12 GPRS/GSM modem. It integrates not
only analog baseband but also power management blocks into one chip and can greatly reduce the
component count and make smaller PCB size. Besides, MT6223D is capable of SAIC (Single
Antenna Interference Cancellation) and AMR speech.
Based on 32 bit ARM7EJ-STM RISC processor, MT6223D provides an unprecedented
platform for high quality Modem performance.
Platform
MT6223D runs the ARM7EJ-STM RISC processor at up to 52Mhz, thus providing best trade-off
between system performance and power consumption.
For large amount of data transfer, high performance DMA (Direct Memory Access) with
hardware flow control is implemented, which greatly enhances the data movement speed while
reducing MCU processing load.
Targeted as a modem-centric platform for mobile applications, MT6223D also provides hardware
security digital rights management for copyright protection. For further safeguarding, and to protect
manufacturer's development investment, hardware flash content protection is also provided to
prevent unauthorized porting of software load.
Memory
MT6223D supports up to 2 external state-of-the-art devices through its 16-bit host interface.
Devices such as burst/page mode Flash, page mode SRAM, and Pseudo SRAM are supported. To
minimize power consumption and ensure low noise, this interface is designed for flexible I/O
voltage and allows lowering of supply voltage down to 1.8V. The driving strength is configurable for
signal integrity adjustment. The data bus also employs retention technology to prevent the bus
from floating during turn over.
Multi-media
MT6223D utilize high resolution audio DAC, digital audio, and audio synthesis technology to
provide superior audio features., e.g. MP3 ring tone.
Connectivity, and Storage
MT6223D supports UART as well as Bluetooth interface. Also, necessary peripheral blocks are
embedded for a voice centric phone: Keypad Scanner with the capability to detect multiple key
presses, SIM Controller, Alerter, Real Time Clock, PWM, Serial LCD Controller, and General
Purpose Programmable I/Os.
Audio
Using a highly integrated mixed-signal Audio Front-End, architecture of MT6223D allows for
easy audio interfacing with direct connection to the audio transducers. The audio interface
integrates D/A and A/D Converters for Voice band, as well as high resolution Stereo D/A
Converters for Audio band. In addition, MT6223D also provides Stereo Input and
Analog Mux. MT6223D also supports AMR codec to adaptively optimize speech and audio quality.
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