June 2, 2009
DS32EL0421, DS32ELX0421
125 – 312.5 MHz FPGA-Link Serializer with DDR LVDS
Parallel Interface
General Description
Features
The DS32EL0421/DS32ELX0421 is a 125 MHz to 312.5 MHz
(DDR) serializer for high-speed serial transmission over FR-4
printed circuit board backplanes, balanced cables, and optical
fiber. This easy-to-use chipset integrates advanced signal
and clock conditioning functions, with an FPGA friendly inter-
face.
5-bit DDR LVDS parallel data interface
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Programmable transmit de-emphasis
Configurable output levels (VOD
)
Selectable DC-balanced encoder
Selectable data scrambler
Remote Sense for automatic detection and negotiation of
link status
The DS32EL0421/DS32ELX0421 serializes up to 5 parallel
input LVDS channels to create a maximum data payload of
3.125 Gbps. If the integrated DC-balance encoding is en-
abled, the maximum data payload achievable is 2.5 Gbps.
On chip LC VCOs
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Redundant serial output (ELX device only)
The DS32EL0421/DS32ELX0421 serializers feature remote
sense capability to automatically detect and negotiate link
status with its companion DS32EL0124/DS32ELX0124 de-
serializers without requiring an additional feedback path.
Data valid signaling to assist with synchronization of
multiple receivers
Supports AC- and DC-coupled signaling
Integrated CML and LVDS terminations
Configurable PLL loop bandwidth
Programmable output termination (50Ω or 75Ω).
Built-in test pattern generator
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The parallel LVDS interface reduces FPGA I/O pins, board
trace count and alleviates EMI issues, when compared to tra-
ditional single-ended wide bus interfaces.
The DS32EL0421/DS32ELX0421 is programmable through
a SMBus interface as well as through control pins.
Loss of lock and error reporting
Configurable via SMBus
Target Applications
48-pin LLP package with exposed DAP
Imaging: Industrial, Medical Security, Printers
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Displays: LED walls, Commercial
Key Specifications
Video Transport
1.25 to 3.125 Gbps serial data rate
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Communication Systems
125 to 312.5 MHz DDR parallel clock
Test and Measurement
-40° to +85°C temperature range
Industrial Bus
>8 kV ESD (HBM) protection
Low Intrinsic Jitter — 35ps at 3.125 Gbps
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Typical Application
30032101
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