STA1102R

Functional description

Doc ID 16470 Rev 5

7/18

3

Functional description

3.1

Equalizer

The adjustable input equalizer reduces system jitter and attenuation from long or lossy

cables. Shaping is performed by the gain stage of the equalizer to compensate the signal.

Note:

9 dB EQ is useful for signal recovery over long PCB track, e.g. 10” FR4.

3.2

Pre-emphasis

The STA1102R provides at each output a differential pair of 1-bit programmable pre-

emphasis to compensate for losses across long PCB tracks and interconnects after the re-

driver output. Below, the truth table of the pre-emphasis control is shown:

Table 3.

Input equalizer truth table

EN

E1

E2

Function

0x

x

Low power mode:

input stage disabled for minimum power consumption

100

Normal operation mode:

both CH1 and CH2 7dB EQ

101

Normal operation mode:

CH1 7dB EQ; CH2 9dB EQ

110

Normal operation mode:

CH1 9dB EQ; CH2 7dB EQ

111

Normal operation mode:

both CH1 and CH2 9dB EQ

Table 4.

Pre-emphasis truth table

EN

D1

D2

Functions

0xx

Low power mode:

output driver disabled; output driven to HiZ

10

0

Normal operation mode:

both CH1 and CH2 0 dB pre-emphasis

10

1

Normal operation mode:

CH1 0 dB pre-emphasis; CH2 2.5 dB pre-emphasis

11

0

Normal operation mode:

CH1 2.5 dB pre-emphasis; CH2 0 dB pre-emphasis

11

1

Normal operation mode:

both CH1 and CH2 2.5 dB pre-emphasis

Obsolete

Product(s)

- Obsolete

Product(s)