Cypress CYS25G0101DX-ATC

CYS25G0101DX-ATC Evaluation Board User’s Guide

5.3 Analog Line Loopback

In the Analog Line Loopback mode, serial data (from IN±) will loop through directly from serial input buffer to the serial output buffer

(OUT±). Figure 6 shows the data path (bold line) of the Analog Line Loopback mode. To select the Analog Line Loopback mode:

1. SW1-4 (LOOPA) must be in ON position and SW1-3 (LINELOOP) must be in OFF position.

2. All other dip switches must be in their default positions as stated in Table 4

3. TEST0, jumper J6 must be opened

4. Apply the Testing Hookup illustrated in Figure 8 to Figure 10

Figure 6. Analog Line Loopback Mode Data Path

TXD

15:0

TX PLL

x16

/16

RXD

15:0

SHIFTER RX CDR

PLL

Input

Output

FIFO

(5byte) SHIFTER

/16

RXCLKOUTREFCLKTXCLKTXCLKIN

DIAGLOOP

(SW1-2) = OFF

LINELOOP

SW1-3 = OFF

LOOPA

SW1-4 = ON

IN±

OUT±

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