STA1102R Datasheet, PDF (7/18 Pages) STMicroelectronics – 3 Gbps, 2 differential-pair channel eSATA signal re-driver

STA1102R
3
Functional description
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.
Table 3. Input equalizer truth table
EN
E1
E2
Function
Low power mode:
bsolete ^Product(s) _Note:
Obsolete ^{Product(s) - O 3.2}
0
x
x
input stage disabled for minimum power consumption
Normal operation mode:
1
0
0
both CH1 and CH2 7dB EQ
Normal operation mode:
1
0
1
CH1 7dB EQ; CH2 9dB EQ
Normal operation mode:
1
1
0
CH1 9dB EQ; CH2 7dB EQ
Normal operation mode:
1
1
1
both CH1 and CH2 9dB EQ
9 dB EQ is useful for signal recovery over long PCB track, e.g. 10” FR4.
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 4.
EN
0
1
Pre-emphasis truth table
D1
D2
Functions
Low power mode:
x
x
output driver disabled; output driven to HiZ
Normal operation mode:
0
0
both CH1 and CH2 0 dB pre-emphasis
Normal operation mode:
1
0
1
CH1 0 dB pre-emphasis; CH2 2.5 dB pre-emphasis
Normal operation mode:
1
1
0
CH1 2.5 dB pre-emphasis; CH2 0 dB pre-emphasis
Normal operation mode:
1
1
1
both CH1 and CH2 2.5 dB pre-emphasis
Doc ID 16470 Rev 5
7/18