Circuit Description - Samsung STH-N271 Service Manual

Single band mobile cellular phone

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Table of Contents

ARM Address Range

0000 0000

0000 0003

0000 0004

0000 1FFF

0002 0000

0002 0FFF

0004 0000

0005 FFFF

0080 0000

00FF FFFF

0100 0000

017F FFFF

0180 0000

01FF FFFF

0200 0000

027F FFFF

HOST CPU (inside of BEC:U203)

ARM7TDMI 32-bit microprocessor is used for the main call processing. The CPU controls all the circuitry. The

reference clock 14.4 MHz, coming from the output of the TCXO (OSC302), is connected to VCTCXO_IN (pin

F3). Digital Only, additional crystal oscillator (Y201) of 32.768kHz is connected to pin B2 of the BEC. The

interface circuitry consists of reset circuit, address bus (A0-A21), data bus (AD0-AD15), control signals

(MEMWEB, MEMOEB, SRAM_CS, FLASH_CS, DISPLAY_CS, UBE etc), GPIOs, and the communication ports.

The communication ports includes the UART1 and 2, the JTAG, and the SCI. The UART1 supports HP

equipment interface, down loading, and data service. The UART2 and the JTAG are used for the software

debugging. The SCI supports the Diagnostic Monitor (DM) function.

FLASH ROM (inside of U202)

The 32Mbit FLASH ROM is used to store code of the application program. Using the down-loader program,

this application program can be changed even after the mobile is fully assembled.

SRAM (inside of U202)

The 4Mbit SRAM is used to store the internal flag information, call processing data, and timer data.

Key Pad

The Key Pad is belong to main board. For key-press recognition, the structure of key is consisted of 8 x 3

matrix, which is used GPIO input signal SCAN0-7 and GPIO output signal KEY0-2 of BEC.

LCD

LCD module is connected to main board directly by U103. This contains an LCD controller,. An LCD controller

controls the information of displaying from the BEC (parallel 8-bit data) to the LCD.

BASEBAND ENGIN (inside of U203)

This part mainly interface with IFC (U101) and RF part. As for interface of IFC, that will be explained detail in

next section. As important signals are PREAMP_G for receiver path, PA-GATE, ALC_EN for transmitter path,

PLL_DATA, PLL_CLK, PLL_STRB1 for PLL synthesizer, RX_BAT, TX_BAT for power management.

Table2-1. ARM Memory Map

ARM Memory Map

Data

32/16

8/16

SAMSUNG Proprietary-Contents may change without notice

Block Size

4 Byte

Internal ROM

8K Byte

Internal RAM

4K Byte

Internal ROM

Internal Peripherals

Up to 8 M Byte

11-3

STH-N271