DS50PCI402EVK/NOPB National Semiconductor, DS50PCI402EVK/NOPB Datasheet - Page 8

• Manufacturer Part Number: DS50PCI402EVK/NOPB
• Description: BOARD EVALUATION DS50PCI402
• Manufacturer: National Semiconductor
• Series: PowerWise®r

Specifications of DS50PCI402EVK/NOPB

• Main Purpose: Interface, Transceiver, PCI Express
• Embedded: No
• Utilized Ic / Part: DS50PCI402
• Primary Attributes: 5 Gbps Quad Lane Bidirectional Buffer & Equalizer
• Secondary Attributes: 3.3V LVCMOS Input Tolerant for SMBus Interface
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: DS50PC1402EVK/NOPB

www.national.com
SD_TH resistor value can be set from 0 through 80K Ohms to achieve desired idle detect threshold, see
SD_TH resistor value (Ω) (connect from pin to GND)
TABLE 6. Receiver Electrical Idle Detect Threshold Adjust (Analog input - Connect Resistor to GND or Float)
TXIDLEA/B
Float
0
1
Float (no resistor required)
This state is for lossy media, dedicated Idle threshold detect circuit disabled, output follows input based
recommended default state. Output driven to Idle if diff input signal less than value set by SD_TH pin.
80K
0
Float enables automatic idle detection. Idle on the input is passed to the output. This is the
FIGURE 1. Typical Idle threshold vs SD_TH resistor value
TABLE 5. Idle Control (3–Level Input)
Manual override, output forced to Idle. Diff inputs are ignored.
on EQ settings. Idle state not guaranteed.
approx 130mV.
8
Typical Receiver Electrical Idle Detect Threshold (DIFF p-p)
Function
130mV (default condition)
225mV
20mV
30107393
Figure
1. 8K Ohm is