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SAMSUNG Proprietary-Contents may change without notice
SGH-X450 Circuit Description
2-6
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Some PPI pins has many special functions. CP_KB[0~9] receive the status from key FPCB and are used for the
communicatios using data link cable(DEBUG_DTR/RTS/TXD/RXD/CTS/DSR).
And UP_CS/SCLK/SDI, control signals for PSC2106 are outputted through PPI pins. It has signal port for
charging(CHG_DET), SIM_RESET and FLIP_SNS with which we knows open.closed status of folder. It has JTAG control
pins(TDI/TDO/TCK) for ARM core and DSP core. It recieves 13MHz clock in CKI pin from external TCXO and receives
32.768KHz clock from X1RTC. ADC(Analog to Digital Convertor) part receives the status of temperature, battery type and
battery voltage. And control signals(DSP_INT, DSP_IO and DSP_RWN) for DSP core are used. It enables main LCD with
DSP IP pins.
7) CSP1093
CSP1093 integrates the timing and control functions for GSM 2+ mobile application with the ADC and DAC functions.
The CSP1093 interfaces to the trident, via a 16-bit parallel interface. It serves as the interface that connects a DSP to the
RF circuitry in a GSM 2+ mobile telephone. DSP can load 148 bits of burst data into CSP1093
’
s internal register, and
program CSP1093
’
s event timing and control register with the exact time to send the burst. When the timing portion of
the event timing and control register matches the internal quarter-bit counter and internal frame counter, the 148 bits in the
internal
Register are GMSK modulated according to GSM 2+ standards. The resulting phase information is translated into I and Q
differential output voltages that can be connected directly to an RF modulator at the TXOP and TXON pins. The DSP is
notified when the transmission is completed. For receiving baseband data, a DSP can program CSP1093
’
s event timing and
control register with the exact time to start receiving I and Q samples through TXIP and TXIN pins. When that time is
reached, the control portion of the event timing and control register will start the baseband receive section converting I
and Q sample pairs. The samples are stored in a double-buffered register until the register contains 32 sample pairs.
CSP1093 then notifies the DSP which has ample time to read the information out before the next 32 sample pairs are
stored. The voice band ADC converter issues an interrupt to the DSP whenever it finishes converting a 16-bit PCM word.
The DSP then reads the new input sample and simultaneously loads the voice band output DAC converter with a new
PCM output word. The voice band output can be connected directly to a speaker via AOUTAN and AOUTAP pins and
be connected to a Ear-mic speaker via AOUTBN and AOUTBP pins.
8) X-TAL(13MHz)
This system uses the 13MHz TCXO, TCO-9141B, Toyocom. AFC control signal form CSP1093 controls frequency from
13MHz x-tal. It generates the clock frequency. This clock is fed to CSP1093,Trident,YMU762 and Silab solution.