AMIS-52100 Datasheet, PDF (12/26 Pages) AMI SEMICONDUCTOR – Transceiver with Clock and Data Recovery

AMIS-52100 Low-Power Transceiver with Clock and Data Recovery
Data Sheet
9.0 Circuit Functional Description
The functions of the AMIS-52100 are presented in this section. These functions are:
• Receiver
• Transmitter
• Sniff
• Quick Start
• Data Detection
• Clock and Data Recovery
• Application Wakeup
• I²C Protocol
• Registers
• Alternative Wakeup
• Power on-Reset/Brownout
9.1 Receiver
RF signals often suffer from reflections along the path of propagation. These reflected signals arrive at the receiver antenna with
different phases or time delays. The different phases of the reflected signals causes the signal strength at the receiver to vary. This
variation can be large enough to cause the receiver to miss information. The AMIS-52100 sums the signals from the dual receiver
channels inside the data detection circuits. This reduces the effect of the multipath reflections. The receivers in the AMIS-52100 require
that the frequency be trimmed, the receiver oscillator frequency be tuned, the data rate filters be selected, and a signal threshold set as
shown in Table 20.
Table 21 lists some characteristic parameters for the receivers. Figure 7 shows a typical received data waveform.
Table 20: Receiver Control Registers
RX1 or RX2 Receiver Register Control
Register (HEX) Name
Bits
0x00
ANT1 trim
All
0x01
ANT2 trim
All
0x05
0x0a
RX XTAL tune
All
Data threshold
All
0x0c
ANT1 enable
0
ANT2 enable
1
RX enable
3
0x0f
Data filter
4,5,6
0x1e
TX/RX invert
5
States
Comments
Inverse relationship register
value to internal capacitance
Inverse relationship register
value to internal capacitance
Reference level for detecting data
logic state
0
Antenna port is off
1
Antenna port is on
0
Antenna port is off
1
Antenna port is on
0
Receiver is off
1
Receiver is on
000 1.1kHz
001 2.3kHz
010 5.2kHz
011 10.4kHz
100 1.18kHz
101 2.57kHz
110 7.0kHz
111 20.45kHz
0
Normal levels
1
Inverted
AMI Semiconductor – Rev 4.0, Mar. 06 – M-20535-004
12
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