ADSL2 + line drive solution (1)

DSL (digital user line) is a technology that converts the current twisted-pair telephone lines into access channels for multimedia and high-speed data communication. Connect the device to a twisted pair telephone line to generate three information channels. The modem separates high-speed downstream channels, medium-speed downstream channels, and POTS (conventional telephone services) with filters. These channels depend on the implementation of the structure (see table 1 ).

Line Interface-ADSL Remote End

Figure 1 shows the typical analog line interface used for ADSL (Asymmetric Digital user line. Separate upstream and downstream signals from telephone lines using a hybrid circuit and line Transformer. Here, the focus is on the transmission path. Note the following principles.

Table 1 ADSL Spectrum

Figure 1 Typical ADSL Line Interface

Figure 2 TS615 Power Reduction Mode

Figure 3 differential line drive consisting of TS616 (or TS615) with a single power supply of + 12 V

Power Supply

Turns ratio of line Transformer;

The output capability of the driver (maximum output swing, output current, and the relationship between linearity and load );

Line matching technology;

Insertion Loss of hybrid circuits.

Figure 4 differential line drive consisting of TS616 (or TS615) with + 5 V single Power Supply

Figure 5 Power Consumption (+ 12 V and + 5 V power supply)