Chipset RSKM Characteristics

Over recommended operating supply and temperature ranges unless otherwise specified.(Notes 4, 7). See Applications Infor-

mation section for more details on this parameter and how to apply it.

Symbol

Parameter

Min

Typ

Max

Units

RSKM

Receiver Skew Margin without

Deskew in non-DC Balance Mode,

(Figure 13), (Note 5)

f = 112 MHz

170

ps

f = 100 MHz

170

240

ps

f = 85MHz

300

350

ps

f = 66MHz

300

350

ps

RSKM

Receiver Skew Margin without

Deskew in DC Balance Mode,

(Figure 13), (Note 5)

f = 112 MHz

170

ps

f = 100 MHz

170

200

ps

f = 85 MHz

250

300

ps

f = 66 MHz

250

300

ps

RSKMD

Receiver Skew Margin with Deskew

in DC Balance, (Figure 14),

(Note 6)

f=33to80

MHz

0.25TBIT

ps

RDR

Receiver Deskew Range

f = 80 MHz

TBIT

RDSS

Receiver Deskew Step Size

f = 80 MHz

0.3 TBIT

ns

Note 1: “Absolute Maximum Ratings” are those values beyond which the safety of the device cannot be guaranteed. They are not meant to imply that the device

should be operated at these limits. The tables of “Electrical Characteristics” specify conditions for device operation.

Note 3: Current into device pins is defined as positive. Current out of device pins is defined as negative. Voltages are referenced to ground unless otherwise

Note 4: The Minimum and Maximum Limits are based on statistical analysis of the device performance over voltage and temperature ranges. This parameter is

functionally tested on Automatic Test Equipment (ATE). ATE is limited to 85MHz. A sample of characterization parts have been bench tested to verify functional

performance.

Note 5: Receiver Skew Margin (RSKM) is defined as the valid data sampling region at the receiver inputs. This margin takes into account transmitter output pulse

positions (min and max) and the receiver input setup and hold time (internal data sampling window, RSPOS). This margin allows for LVDS interconnect skew,

inter-symbol interference (both dependent on type/length of cable) and clock jitter (TJCC).

RSKM

≥ cable skew (type, length) + source clock jitter (cycle to cycle,TJCC) + ISI (if any). See Applications Information section for more details.

Note 6: Receiver Skew Margin with Deskew (RSKMD) is defined as the valid data sampling region at the receiver inputs. The DESKEW function will constrain the

receiver’s sampling strobes to the middle half of the LVDS bit and removes (adjusts for) fixed interconnect skew. This margin (RSKMD) allows for inter-symbol

interference (dependent on type/length of cable), Transmitter Pulse Position (TPPOS) variance, and LVDS clock jitter (TJCC).

RSKMD

≥ ISI + TPPOS(variance) + source clock jitter (cycle to cycle, TJCC). See Applications Information section for more details.

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