CLINK3V48BT-133 National Semiconductor, CLINK3V48BT-133 Datasheet - Page 16

• Manufacturer Part Number: CLINK3V48BT-133
• Description: BOARD EVAL FOR DS90CR485, 486
• Manufacturer: National Semiconductor

Specifications of CLINK3V48BT-133

• Main Purpose: Interface, SerDes (Serializer / De-Serializer)
• Embedded: No
• Utilized Ic / Part: DS90CR485, DS90CR486
• Primary Attributes: Serializes 48 LVCMOS/LVTTL to 8 LVDS, 66 ~ 133 MHz
• Secondary Attributes: Transmits over 2 Meter 3M MDR LVDS Cable
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

DC Balance mode
DC balance mode helps minimize the short-and-long-term DC bias on the LVDS
lines to facilitate driving long cables. To use this function, both transmitter and
receiver DC balance (BAL) pins must be switched ON.
Designator
SW2
SW3
Cable Deskew
The receiver DESKEW function removes fixed pair-to-pair skew between the
LVDS clock and data. The receiver performs deskew calibration automatically on
power up provided that sufficient transitions appear on its LVDS data inputs
during this time (4096 clock cycles). Automatic deskew on power up is enabled
by setting pin CON1 (SW3) to HIGH and the DESKEW pin (SW3) to DEFAULT.
In addition, deskew calibration can be initiated any time by toggling the DESKEW
pin (SW3) for more than one clock cycle. Once deskew is initiated, the LVDS
data inputs must have edge transitions for the receiver to perform the deskew
operation. Unlike older chipsets, the DS90CR486 receiver deskew operates in
either DC balance or non-DC-balance mode (transmitter and receiver must be in
the same DC balance mode).
NOTE: DESKEW pin must set to “DEFAULT” for normal operation. Setting
the pin to “RE-START DESKEW” will continuously recalibrate the sampling
strobes. Data outputs are LOW during this period.
DS90CR485/486 Evaluation Kit User Manual
Rev. 1.01
RE-START DESKEW
RE-START DESKEW
PRBS DISABLE
PRBS DISABLE
DC BAL OFF
DC BAL OFF
DC BAL OFF
DC BAL OFF
PWR DOWN
PWR DOWN
PWR DOWN
PWR DOWN
PRBS_15
PRBS_15
PLLSEL
PLLSEL
PLLSEL
PLLSEL
TEST1
TEST1
TEST2
TEST2
CON1
CON1
Settings
HIGH
HIGH
DC BAL ON
DC BAL ON
PRBS ENABLE
PRBS ENABLE
PRBS_23
PRBS_23
HIGH
HIGH
HIGH
HIGH
DEVICE ENABLE
DEVICE ENABLE
DEFAULT
DEFAULT
HIGH
HIGH
HIGH
HIGH
DC BAL ON
DC BAL ON
DEVICE ENABLE
DEVICE ENABLE
16 of 32
Note
Transmit DC balance ON
Receive DC balance ON