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SAMSUNG Proprietary-Contents may change without notice
Circuit Description
This Document can not be used without Samsung's authorization
2-3
4. 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 seperated from the matrix. So power on/off
signal is connected with PCF50601 to enable PCF50601. Key LED is consisted of
four white LED for sub key and
six white LED for main key. Four white LED for sub key use the 3.3V supply voltage. "SUB_BACKLIGHT_KEY_ON"
signal enables 3.3V LDO for sub key backlight. Six white LED use the
"VDD_KEY" supply voltage.
OM6359 enables six white LED.
"FLIP" informs the status of slide (open or closed) to the OM6359. This uses the hall effect IC, SH248GSP.
A magnet under main LCD enables SH248GSP.
5. EMI ESD Filter
This system uses the EMI ESD filter, EMIF09 to protect noise from IF CONNECTOR part.
6. 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.
7. Battery Charge Management
A complete constant-current/constant-voltage linear charger for single cell lithium-ion batteries.
If TA connected to phone, "V_EXT_CHARGE" 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.
8. Audio
EARP_P and EARP_N from OM6359 are connected to the main speaker. AUXSP is connected to the Hands free kit.
MIC_P and MIC_N are connected to the main MIC. And AUX_MIC_P and AUX_MIC_N are connected to earmicrophone.
YMU765_MA5 is a LSI for portable telephone that is capable of playing high quality music by utilizing FM synthesizer
and ADPCM decorder that are included in this device.
As a synthesis, YMU765_MA5 is equipped 32 FM voices and 32 Wave Table voices. 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 YMU765_MA5 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. Moreover, the registers of the FM synthesizer can be operated directly for real time sound
generation, allowing, for example, utilization of various sound effects when using the game software installed in the
portable telephone.
YMU765_MA5 includes a speaker amplifier with high ripple removal rate whose maximum output is 580mW
(SPVDD=3.6V). The device is also equipped with conventional function including a vibartor.