AMIS-52150 Datasheet, PDF (19/25 Pages) AMI SEMICONDUCTOR – Low-Power Transceiver with Clock and Data Recovery

AMIS-52150
Low-Power Transceiver with Clock and Data Recovery
Data Sheet
Table 26: Auto Slice Control Registers
Auto Slice Control Registers
Register (HEX) Name
0x0a
DATA SLICE
THRESHOLD
0x0f
HYSTERESIS
AUTOSLICE
Bits States Comments
All
Set a fixed reference level for the slice output to be
compared to in the DAC mode
0,1
00
0mV hysteresis used in the threshold circuit
01
20mV hysteresis used in the threshold circuit
10
50mV hysteresis used in the threshold circuit
11
100mV hysteresis used in the threshold circuit
2,3
00
DAC mode used for data detection (DEFAULT)
01
Average mode used for data detection
10
Peak mode used for data detection
11
DAC mode used for data detection
9.6 Data and Clock Recovery
Data recovered in a noisy environment or from a weak RF signal is usually jittery. The AMIS-52150 can remove much of that data jitter
by recovering a synchronous clock signal from the incoming data. The device can be set to achieve auto slice data detection. The clock
and data recovery circuits can be programmed to generate a data clock for synchronously clocking the data output from the transceiver,
removing much of the jitter in this process. The AMIS-52150 has an internal PLL that must be programmed to the frequency of the data
by setting the values in the FWORD register and setting the coefficients of the filter. If these values are close to the data rate, the
device will recover the data clock from the incoming detected data. The CDR circuit can also be set to a given tolerance with respect to
the frequency difference between the target data rate and the actual data rate, in order to improve the performance of the CDR
function. The CDR circuit can also be configured to reset after a programmed number of data time periods if no data is received. This
“stop and check” function allows the CDR circuit to re-acquire the clock data when new data is received, maintaining better clock to
data synchronization.
Table 27 lists the registers associated with the data and clock recovery function. For further details, refer to the application note titled
“AMIS-52150 Clock and Data Recovery Circuit Operation and Set-Up”.
AMI Semiconductor – Apr. 07 – M-20535-006
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