msm7583 Oki Semiconductor, msm7583 Datasheet - Page 4

• Manufacturer Part Number: msm7583
• Description: Shift Qpsk Modem
• Manufacturer: Oki Semiconductor

¡ Semiconductor
PIN AND FUNCTIONAL DESCRIPTIONS
TXD
TXCI
TXCO
TXW
I+, I–
Q+, Q–
Transmit data input for 384 kbps.
Transmit clock input.
When the control register CR0 - B6 is “0”, a 384 kHz clock pulse synchronous with TXD should
be input to this pin. This clock pulse should be continuous because this device uses APLL to
generate internal clock pulses.
When CR0 - B6 is “1”, a 3.84 MHz clock pulse should be input to this pin. When the 3.84 MHz
clock pulse is applied to TXCI, TXCO outputs a 384 kHz clock pulse, which is generated by
dividing the TXCI input by 10. The transmit data, synchronous 384 kHz clock pulse, should be
input to the TXD. In this case the device does not use APLL, and the 3.84 MHz clock pulse need
not be continuous. (Refer to Fig. 1.)
Transmit clock output.
When CR0 - B6 is “0”, TXCO outputs the 384 kHz clock pulse (APLL output) for monitoring
purposes. When CR0 - B6 is “1”, this pin outputs a 384 kHz clock pulse generated by dividing
the TXCI input by 10. (Refer to Fig. 1.)
Transmit data window signal input.
The transmit timing signal for the burst data is input to the device through this pin. If TXW pin
is “1”, modulation data is output. (Refer to Fig. 1.)
Quadrature modulation signal I component differential analog outputs.
The level of the outputs is 500 mVpp with 1.6 Vdc as center value. The output pin load
conditions are: R 10 kW, C £ 20 pF. The gain of these pins can be adjusted using the control
registers CR1 - B7 to B4, and the offset voltage at the I– pin can be adjusted using CR3 - B7 to
B3.
Quadrature modulation signal Q component differential analog outputs.
The level of the outputs is 500 mVpp with 1.6 Vdc as center value. The output pin load
conditions are: R 10 kW , C £ 20 pF. The gain of these pins can be adjusted using the control
registers CR1 - B3 to B0, and the offset voltage at the Q– pin can be adjusted using CR4 - B7 to
B3.
MSM7583
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