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SAMSUNG Proprietary-Contents may change without notice
Circuit Description
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This Document can not be used without Samsung's authorization
The signal which informs the state of LCD is whether input or output, is required. But in this system, there is no input
state from LCD. So only "HA(1)" signal is used to indicate write data or command to LCD. Power signals for LCD are
"VBAT and "VDD3".
"SPK_P" and "SPK_N" are used for audio speaker containing voice or melody. And "VDD_VIB" from PCF50601
enables the motor.
2-2-3. Key
This is consisted of key interface pins among OM6359, KBIO(0:7). These signals compose the matrix. Result of matrix
informs the key status to key interface in the OM6359. Power on/off key is separated from the matrix. So power on/off
signal is connected with PCF50601 to enable PCF50601. Twelve key LEDs
are use the "VDD_KEY" as supply voltage.
"FLIP" informs the status of folder (open or closed) to the OM6359. This uses the hall effect IC, A321ELH-SAMSUNG.
A magnet under main LCD enables A321ELH-SAMSUNG.
2-2-4. EMI ESD Filter
This system uses the EMI ESD filter, EMIF09 to protect noise from IF CONNECTOR part.
2-2-5. IF connetor
It is 18-pin connector. They are designed to use VBAT, V_EXT_CHARGE, TXD0, RXD0, RTS0, CTS0, JIG_REC,
CHARGER_OK, RXD1, TXD1, AUX_MIC, AUX_SPK and GND. They connected to power supply IC, microprocessor
and signal processor IC.
2-2-6. Battery Charge Management
A complete constant-current/constant-voltage linear charger is used for single cell lithium-ion batteries.
If TA connected to phone, "+DCVOLT" enable charger IC and supply current to battery.
When fault condition caused, "CHG_ON" signal level change low to high and charger IC stop charging
process.
2-2-7. Audio
EARP_P and EARP_N from OM6359 are connected to the main speaker. MIC_P and MIC_N are connected to the main
MIC. YMU762 is a synthesizer LSI for mobile phones. It is a LSI as an input/output device for sound sources, which is
the mobile phones, such as AAC, in addition to ringing-melodies.
As a synthesis, YMU762 is equipped 32 voices with different tones. Since the device is capable of simultaneously
generating up to synchronous with the play of the FM synthesizer, various sampled voices can be used as sound effects.
Since the play data of YMU762 are interpreted at anytime through FIFO, the length of the data(playing period) is not
limited, so the device can flexibly support application such as incoming call melody music distribution service.
The hardware sequencer built in this device allows playing of the complex music without giving excessive load to the
CPU of the portable telephones.
For the purpose of enabling YMU762 to demonstrate its full capabilities, Yamaha purpose to use "SMAF:Synthetic music
Mobile Application Format" as a data distribution format that is compatible with multimedia. Since the SMAF takes a
structure that sets importance on the synchronization between sound and images, various contents can be written into it
including incoming call melody with words that can be used for training karaoke, and commercial channel that combines