S1M8656A Datasheet, PDF (18/26 Pages) Samsung semiconductor – CDMA/AMPS Dual Mode IF/ baseband IC

S1M8656A
RX IF/BBA WITH AGC
(8) The following 1-BIT data is a dummy data, which marks the end of the 8-bit data transmission and beginning
of the next data to be sent.
(9) The following 1-bit decides on whether the master will drive the data line or the slave will. If this bit is '1', the
master will drive , but if '0' the slave will drive the data line.
(10) The following 7-bit data is the register address of the specified slave device.
(11) The following high 1-BIT data is a dummy data.
(12) The following 8-BIT data is the data in the device to be driven.
(Continous data transmission such as this can be ended with a 1-byte transmission or can be read/written
repeatedly.)
(13) After the last data is sent, the data line opens and becomes high;
(14) the CLK continues for half the 1-clock cycle and then becomes high;
(15) and the STB becomes high as soon as the clock becomes high and this marks the end of data transmission.
Modes of Operation
S1M8656A can be controlled by existing parallel control inputs such as BBA 2.0 or by the SPI bus.
The modes of operation consists of digital state FMB, IDLEB, and SLEEPB modes; Table 2 shows the various
modes.
Mode
CDMA talk
CDMA idle
CDMA sleep
FM talk
FM idle
Rx slot
Table 2. Mode control in the Parallel mode control
FMB
IDLEB
SLEEPB
CHIPx8
H
H
H
On
H
L
H
On
H
L
L
Off
L
H
X
On
L
L
H
Off
L
L
L
Off
TCXO/N
On
On
On
On
On
On
A Rx slot which is not in the existing BBA is shown in the table above. This function was installed for the new FM
Slotted mode. The reason for this new slot is simple. All users are aware of the need to quickly convert from the
sleep mode to the idle mode and that PLL related functions are the slowest to set-up. This is because the PLL
incorporates many external time constants and the large capacitor that is includes takes a long time to charge
and discharge. As one measure, the external time constant could be changed or PLL related blocks could be left
on completely. Here, the Rx slot function in the BBA leaves the VCO completely on. The Rx slot function leaves
the Rx VCO on only when IDLEB is low, SLEEP is low and FMB is low, but an additional 4.5mA of current is
consumed. Even if the RXSLOTB is low in the FM idle mode, remains in the FMSLOT mode.
18