Datasheet

TLK1221
SLLS713C –FEBRUARY 2007–REVISED SEPTEMBER 2009....................................................................................................................................... www.ti.com
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
DESCRIPTION (CONTINUED)
This device supports the defined 10-bit interface (TBI). In the TBI mode, the serializer/deserializer (SERDES)
accepts 10-bit wide 8b/10b parallel encoded data bytes. The parallel data bytes are serialized and transmitted
differentially at PECL-compatible voltage levels. The SERDES extracts clock information from the input serial
stream and deserializes the data, outputting a parallel 10-bit data byte.
A comprehensive series of built-in tests is provided for self-test purposes, including loopback and pseudorandom
binary sequence (PRBS) generation and verification.
The TLK1221 is housed in a high-performance, thermally enhanced, 40-pin QFN package. Use of this package
does not require any special considerations except to note that the pad, which is an exposed die pad on the
bottom of the device, is a metallic thermal and electrical conductor. It is required that the TLK1221 pad be
soldered to the thermal land on the board as it serves as the main ground connection for the device.
The TLK1221 is characterized for operation from –40°C to 85°C.
This device uses a 2.5-V supply. The I/O section is 3.3-V compatible. With the 2.5-V supply, the chipset is very
power-efficient, dissipating less than 200 mW typical power when operating at 1.25 Gbps.
The TLK1221 is designed to be hot-plug capable. A power-on reset causes RBC0, RBC1, the parallel output
signal terminals, TXP, and TXN to be held in the high-impedance state.
Differences Between TLK2201B, TLK2201BI, TLK1221, and TNETE2201
The TLK1221 is the functional equivalent of the TNETE2201. There are several differences between the devices
as noted below. See Figure 12 in the application information section for an example of a typical application
circuit.
• V
CC
is 2.5 V for the TLK2201B, TLK2201BI, TLK1221, and TLK1201A vs 3.3 V for TNETE2201.
• The PLL filter capacitors on pins 16, 17, 48, and 49 of the TNETE2201 are no longer required. The
TLK2201B, TLK2201BI, TLK1221, and TLK1201A use these pins to provide added test capabilities. The
capacitors, if present, do not affect the operation of the device.
• No pulldown resistors are required on the TXP/TXN outputs.
• The TLK1221 is a QFN version of the TLK1211 optimized for TBI-mode operation with no JTAG functionality.
• TLK1221 also has a faster relock time than TLK1201A or TLK2201B.
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Product Folder Link(s): TLK1221