LXT351 datasheet(29/46 Pages) INTEL

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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351

Datasheet

4.0

Application Information

4.1

Transmit Return Loss

Table 15 shows the specification for transmit return loss in E1 applications. The G.703/CH PTT

specification is a Swiss Telecommunications Ministry specification.

Table 16 and Table 17 show the transmit return loss values for E1 and T1 applications.

4.2

Transformer Data

Specifications for transformers are listed in Table 18. A list of transformers recommended for use

with the LXT351 are specified in Table 19.

4.3

Application Circuit

Figure 11 shows a typical LXT351 application.

4.4

Line Protection

On the receive side, 1 k

Ω series resistors protect the receiver against current surges coupled into

the device. Due to the high receiver impedance (40 k

Ω typical) the resistors do not affect the

receiver sensitivity. On the transmit side, Schottky diodes D1-D4 protect the output driver. While

not mandatory for normal operation, these protection elements are strongly recommended to

improve the design robustness

Table 15. E1 Transmit Return Loss Requirements

Frequency Band

Return Loss

ETS 300 166

G.703/CH PTT

51-102 kHz

6 dB

8 dB

102-2048 kHz

8 dB

14 dB

2048 - 3072 kHz

8 dB

10 dB

LXT351 Datasheet(PDF) 29 Page - Intel Corporation