73K324BL
CCITT V.22bis,V.23,V.22,V.21, Bell 212A
Single-Chip Modem w/ Integrated Hybrid
DATA SHEET
DTE USER
NAME
EXCLK
PIN
22
TYPE
I
DESCRIPTION
EXTERNAL CLOCK: This signal is used in synchronous
transmission when the external timing option has been
selected. In the external timing mode the rising edge of
EXCLK is used to strobe synchronous DPSK transmit data
applied to on the TXD pin. Also used for serial control
interface.
RECEIVE CLOCK: The falling edge of this clock output is
coincident with the transitions in the serial received data
output. The rising edge of RXCLK can be used to latch the
valid output data. RXCLK will be valid as long as a carrier is
present.
RECEIVED DATA OUTPUT: Serial receive data is available
on this pin. The data is always valid on the rising edge of
RXCLK when in synchronous mode. RXD will output
constant marks if no carrier is detected.
TRANSMIT CLOCK: This signal is used in synchronous
transmission to latch serial input data on the TXD pin. Data
must be provided so that valid data is available on the rising
edge of the TXCLK. The transmit clock is derived from
different sources depending upon the synchronization mode
selection. In internal mode the clock is generated internally.
In external mode TXCLK is phase locked to the EXCLK pin.
In slave mode TXCLK is phase locked to the RXCLK pin.
TXCLK is always active.
TRANSMIT DATA INPUT: Serial data for transmission is
applied on this pin. In synchronous modes, the data must be
valid on the rising edge of the TXCLK clock. In asynchronous
modes (1200/600 bps or 300/1200 baud) no clocking is
necessary. DPSK data must be 1200/600 bps +1%, -2.5% or
+2.3%, -2.5 % in extended over speed mode.
RXCLK
26
O
RXD
25
O
TXCLK
21
O
TXD
24
I
.
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2005, 2008 TERIDIAN Semiconductor Corporation
Rev 6.1
TERIDIAN [ TERIDIAN SEMICONDUCTOR CORPORATION ]
