DJLXT386LE.B2 Intel, DJLXT386LE.B2 Datasheet - Page 29

• Manufacturer Part Number: DJLXT386LE.B2
• Manufacturer: Intel

Specifications of DJLXT386LE.B2

• Lead Free Status / RoHS Status: Not Compliant

3.3.2
3.3.2.1
3.3.2.2
Datasheet
Transmit Pulse Shaping
The transmitted pulse shape is internally generated using a high speed D/A converter. Shaped
pulses are further applied to the line driver for transmission onto the line at TTIP and TRING. The
line driver provides a constant low output impedance regardless of whether it is driving marks.
Output Driver Power Supply
The output driver power supply (TVCC pins) can be either 3.3V or 5V nominal. When TVCC=5V,
LXT386 drives both E1 (75Ω/120Ω) and T1 100Ω lines through a 1:2 transformer and 11Ω/9.1Ω
series resistors.
When TVCC=3.3V, the LXT386 drives E1 (75Ω/120Ω) lines through a 1:2 transformer and 11Ω
series resistor. A configuration with a 1:2 transformer and without series resistors should be used to
drive T1 100Ω lines.
Removing the series resistors for T1 applications with TVCC=3.3V, improves the power
consumption of the device. See
On the other hand, series resistors in the transmit configuration improve the transmit return loss
performance. Good transmit return loss performance minimizes reflections in harsh cable
environments. In addition, series resistors provide protection against surges coupled to the device.
The resistors should be used in systems requiring protection switching without external relays.
Please refer to
Power Sequencing
For the LXT384, we recommend sequencing TVCC first then VCC second or at the same time as
TVCC to prevent excessive current draw.
Figure 7
for the recommended external line circuitry.
Table
35.
QUAD T1/E1/J1 Transceiver — LXT386
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