73M1903C-EVM Maxim Integrated Products, 73M1903C-EVM Datasheet - Page 27

• Manufacturer Part Number: 73M1903C-EVM
• Description: BOARD DEMO 73M1903C WORLDWIDE
• Manufacturer: Maxim Integrated Products

Specifications of 73M1903C-EVM

• Main Purpose: Interface, Analog Front End (AFE)
• Utilized Ic / Part: *
• Primary Attributes: *
• Secondary Attributes: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Embedded: -

DS_1903C_033
73M1903C Data Sheet
Figure 11: Rx Passband Response at 8 kHz Sample Rate
Remember that the receive signal should not exceed 1.16 Vpk-diff for proper performance for Rxg=11
(0 dB). In particular, if the input level exceeds a value such that one’s density of RBS exceeds 99.5%,
3
sinc
filter output will exceed the maximum input range of the decimation filter and consequently the data
will be corrupted. Also for stability reasons, the receive signal should not exceed 1.16 Vpk differentially.
This value is set at around 65% of the full receive signal of 1.791 Vpkdiff at RXAP/RXAN pins that “would”
correspond to ASDM putting out all ones.
Figure 12 and Figure 13 show the spectrum of 1 kHz tone received at RXAP/RXAN of 1.16 Vpk-diff and
0.5 kHz and 1.0 kHz tones of 0.6 Vpk-diff each, respectively for Fs=8 kHz. Note the effect of FIR
suppressing the noise above 4 kHz but at the same time enhancing (in order to compensate for the
3
passband droop of sinc
filter) it near the passband edge of 4 kHz.
The bandwidth of the receive filter is about 3.585 kHz when Fs=8 kHz. The bandwidth scales with Fs, the
sampling rate. Refer to the
Section 6.3, Modem Transmitter
for more information.
Rev. 5.0
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