73M1903C
Modem Analog Front End
DATA SHEET
SLAVE MODE AND DAISY CHAIN
If the SCLK pin is externally pulled down to ground by a <4.7KΩ resistor, the 79M1903C device is in the
slave mode, after reset. In this mode of operation the serial clock (SCLK) and FS are inputs to 79M1903C
provided by the Master device. The serial clock input must be connected to OSCIN pin while SCLK pin of
73M1903C is unconnected, except for the resistor connected to ground (see Figures 4 and 5). The
73M1903C PLL must be programmed to multiply the serial clock frequency by an appropriate factor in
order to obtain Fsys. Therefore the serial clock has to be continuous and without low frequency jitter (the
high frequency jitter is rejected by the 79M1903C PLL). The SckMode pin is not used since the Master
device provides FS and serial clock.
73M1903C
73M1903C
MCLK
(Master)
OSCIN
SCLK
OSCIN
(Slave)
SDOUT
SDIN
SDIN
SDOUT
SDIN
SDIN
SDOUT
SDOUT
HOST
HOST
(Master)
(Slave)
"x"
"x"
"1/0"
"1/0"
FS
FS
FS
FS
SckMode
SckMode
TYPE
SCLK
SCLK
TYPE
SCLK
"x" : don't care
73M1903C Master Mode
73M1903C Slave Mode
Figure 4: 73M1903C Host connection in master and slave mode
73M1903C
73M1903C
MCLK
SCLK
SDOUT
SDIN
OSCIN (Master)
OSCIN (Slave)
SDOUT
SDIN
SDIN
SDOUT
FS
SDIN
SDOUT
HOST
HOST
"x"
"x"
FS
(Slave)
FS
FS
(Master)
SckMode
"1/0"
"1/0"
SckMode
SCLK
SCLK
FSBD
TYPE
SCLK
TYPE
FSBD
73M1903C
73M1903C
OSCIN
(Slave)
OSCIN
(Slave)
"x" : don't care
SDIN
SDIN
SDOUT
SDOUT
"x"
"x"
"x"
"x"
FS
FS
SckMode
SckMode
SCLK
TYPE
SCLK
TYPE
Daisy chain for Slave mode
Figure 5: 73M1903C Daisy chaining for master/slave mode and slave modes
Daisy chain for Master/Slave mode
In order to daisy chain two or more 73M1903C devices, the master must be programmed into hardware
controlled control frame mode by setting the HC bit (bit 0 in Register01) to “1”, then set FSDEn (bit 3 in
Register06), and then set CkoutEn bit (bit 3 in Register01) to allow the FSD to come through. The first
Page: 9 of 46
© 2005-2008 TERIDIAN Semiconductor Corporation
Rev 4.3
TERIDIAN [ TERIDIAN SEMICONDUCTOR CORPORATION ]
