MTC20154-TQ-C2 ST Microelectronics, Inc., MTC20154-TQ-C2 Datasheet - Page 14

• Manufacturer Part Number: MTC20154-TQ-C2
• Description: Integrated Adsl CMOS Analog Front-end Circuit
• Manufacturer: ST Microelectronics, Inc.

MTC20154
TX Pre-driver Capability
The pre-driver drives an external line power amplifier which transmits the required power to the line.
Table 15. Pre-driver characteristics
TX Filter
The TX filters act not only to suppress the DMT sidebands but also as smoothing filters on the D/A con-
verter’s output to suppress the image spectrum. For this reason they are realised in a time continuous ap-
proach.
ATU-R-TX Filter
The purpose of this filter is to remove out-of-band noise of the ATU-R-TX path echoed to the ATU-R-RX
path. In order to meet the transmitter spectral response, additional filtering is (digitally) performed. The
integrated filter has nominal characteristics shown in table 11:
Table 16. ATU-R-TX filter characteristics
ATU-C-TX Filter
Same filter as ATU-R-RX. Its purpose is now is to remove image frequency of the transmitted signal ac-
cording the ANSI definition.
Table 17. D/A Converter
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TX drive level to the external line driver for max AGC setting
External line driver input impedance:
Pre-driver characteristics:
gain range:
common mode voltage:
output common mode voltage:
Input refered noise
Max. input level
Max. output level
Type
Cut-off frequency
Max. in-band ripple
Description
Number of bits:
Minimum resolution of the D/A converter
Linearity error of the D/A converter
Full scale output range:
Sampling Rate:
Latency:
Description
Value/Units
12 bits
11 bits
< 1 LSB (out of 12 bits)
1 Vpdif +- 5%
8.832 MHz (or 4.416 in alternative mode)
1 sampling clock period
94 nV/
1 Vpd
1 Vpd
4th order chebychef
138 KHz (f0)
0.5 dB
resistive
capacitive
-9 dB...6 dB with step = 1 dB
AVDB/2
30 nV/Hz
Hz
Value/Units
> 200 Ω
2 Vpdif
< 30 pF