CS61582 Datasheet, PDF (23/32 Pages) Cirrus Logic – DUAL T1/E1 LINE INTERFACE

TCLK1, TCLK2 : Transmit Clock (Pins 4, 45)
TPOS1, TPOS2 : Transmit Positive Data (Pins 5, 44)
TNEG1, TNEG2 : Transmit Negative Data (Pins 6, 43)
The transmit clock and data are input on these pins. The signal is driven to the line at TTIP and
TRING. Data on TPOS and TNEG are sampled on the falling edge of TCLK. An input on
TPOS causes a positive pulse to be transmitted at TTIP and TRING, while an input on TNEG
input causes a negative pulse to be transmitted at TTIP and TRING.
Oscillator
1XCLK : One-times Clock Frequency Select (Pin 28)
When 1XCLK is set high, REFCLK must be a 1X clock (i.e., 1.544 MHz for T1 applications or
2.048 MHz for E1 applications). When 1XCLK is set low, REFCLK must be an 8X clock (i.e.,
12.352 MHz for T1 applications or 16.384 MHz for E1 applications).
REFCLK : External Reference Clock Input (Pin 26)
Input reference clock for the receive and jitter attenuator circuits. When 1XCLK is set high,
REFCLK must be a 1X clock (i.e., 1.544 MHz ±100 ppm for T1 applications or 2.048 MHz
±100 ppm for E1 applications). When 1XCLK is set low, REFCLK must be an 8X clock (i.e.,
12.352 MHz ±100 ppm for T1 applications or 16.384 MHz ±100 ppm for E1 applications). The
REFCLK input also determines the transmission rate when TAOS is asserted.
Control
CLKE : Clock Edge (Pin 41)
Controls the polarity of the recovered clock RCLK. When CLKE is high, RPOS and RNEG are
valid on the falling edge of RCLK. When CLKE is low, RPOS and RNEG are valid on the
rising edge of RCLK.
CON01, CON11, CON21 : Configuration for Channel 1 (Pins 58, 53, 51)
CON02, CON12, CON22 : Configuration for Channel 2 (Pins 54, 52, 50)
These pins configure the transmitter (pulse shape, pulse width, pulse amplitude, and driver
impedance) and receiver (slicing level). The CONx1 pins control channel 1 and the CONx2
pins control channel 2. Both channels must be configured to operate at the same data rate on
the line interface (both T1 or both E1).
LLOOP1, LLOOP2 : Local Loopback (Pins 62, 61)
A local loopback is enabled when LLOOP is high. During local loopback, the TCLK, TPOS,
and TNEG inputs are looped back through the jitter attenuator to the RCLK, RPOS, and RNEG
outputs. The data at TPOS and TNEG continues to be transmitted to the line interface unless
overridden by a TAOS request. The inputs at RTIP and RRING are ignored.
RESET : Reset (Pin 25)
A device reset is selected by setting the RESET pin high for a minimum of 200 ns. The reset
function initiates on the falling edge of RESET and requires less than 20 ms to complete. The
control logic is initialized and LOS is set high.
DS224PP1
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