Lattice Rolls Out ispClock5600 Programmable, Zero-Delay Clock Devices

11/22/2004 - Lattice Semiconductor Corporation (NASDAQ: LSCC) announced the addition of in-system programmable (ISPTM) zero-delay clock generator devices to its revolutionary ispClockTM family. These new ispClock5600 clock devices, while pin compatible with the recently announced ispClock5500 devices, offer higher performance and additional functionality. For example, the ispClock5600 devices support external feedback for the PLL in order to support designs that require the generated output clock(s) to be phase aligned with the input clock.

The first devices in the ispClock5600 family, the 10-output ispClock5610 and 20-output ispClock5620, combine a high- performance clock generator with a flexible, Universal Fan-out Buffer. The on-chip, zero-delay clock generator can provide up to 5 clock frequencies, ranging from 10MHz to 320MHz, using a high-performance PLL and clock multiply and divide facilities. The Universal Fan-out Buffer can drive up to 20 clock nets using either single-ended or differential signaling, with individual output control for improved signal and timing integrity.

Additional Features Address Stringent Applications
The ispClock5600 devices are ideally suited for applications that require local circuit board clocks to align their phases to a central backplane clock (e.g., Advanced TCA, Medical Instrumentation, etc.), or to distribute a master clock to a wide variety of ASICs and FPGAs interfacing to the CPU Bus. Like the ispClock5500 family, these devices use seven on-chip 5-bit counters (input, feedback, and five output) to provide fine granularity output frequency selection. The high-performance Universal Fan-out Buffer has a maximum pin-to-pin skew of 50ps, regardless of bank and frequency, while the maximum cycle-cycle (peak-peak) output jitter is less than 60ps, and the period jitter is less than 10 ps (rms). The output skew of each clock net relative to the reference input can be further controlled in delay increments of 200ps (lead or lag) to compensate for differences in circuit board clock network trace length. In addition, both the reference input and the Universal Fan-out Buffers can support a wide variety of popular single-ended and differential logic standards (LVCMOS, LVTTL, HSTL, SSTL, LVDS, LVPECL) at a variety of voltage levels. The input termination and output impedance of each output can be individually tuned to match each trace impedance, resulting in clock nets with high signal integrity.

"With the introduction of the ispClock5600 family, Lattice has substantially increased its serviceable clock generator market, " said Stan Kopec, Lattice vice president of corporate marketing. "Traditionally, as the performance requirements of the system increased, the effort required to generate and distribute clocks grew exponentially. The ispClock5600 devices provide unprecedented convenience to designers without compromising the system specifications, offering faster time to market and reduced board space, as well as improved manufacturability and reliability."

Volume Production of the ispClock5510 Begins
Lattice has also announced that volume production of the second member of the ispClock5500 family, the ispClock5510 device with 10 clock outputs in the 48-pin TQFP package, is underway. The ispClock 5510 joins the ispClock 5520, already in production, and is priced at $10.75 in 1000 piece quantities.

PAC-Designer® Software
The Lattice PC-based mixed signal design tool, PAC-Designer Version 3.2, provides comprehensive support for the ispClock5600 device family. In addition, utilities such as Graphical Skew Editor, Frequency Calculator and Frequency Synthesis support have been enhanced to address a wider range of application issues. Design configurations can be downloaded quickly into ispClock5600 devices via the PC parallel port. This version of the PAC-Designer software can be downloaded for free from

Pricing and Availability
Prices for the first available device, the ispClock5620, start at $21.90 in 1000 piece quantities. The ispClock5620 in a 100-pin TQFP package is available immediately in both commercial (0C to +70C) and industrial (-40C to +85C) temperature grades. PACsystemCLK5620 evaluation kits are also available through authorized Lattice distributors or on the Lattice Web site for $295.

About ispClock Devices: A Comprehensive Improvement Over Traditional Clock Network Design
Lattice is extending the benefits of integration, in-system programmability and superior performance to clock management. Historically, clock networks have been designed using multiple, simple components -- such as fan-out buffers, clock generators, delay lines, zero-delay buffers and frequency synthesizers -- with limited functionality at various levels of the clock hierarchy. Timing errors due to unequal PCB trace lengths have been addressed by using trace length matching through serpentine trace layouts. Trace impedance mismatch has been frequently mitigated by trial and error selection of series resistors.

In contrast, ispClock devices are the first products that conveniently and accurately solve the entire clock tree design problem with a single chip. The ispClock devices compensate for timing errors due to different trace length clock nets through a programmable skew feature, match trace impedances with output impedances by programming each output characteristic, and reduce EMI by programming output switching speed or slew rate. This results in board space savings, improved signal integrity, a simpler clock net hierarchy, improved timing convergence and lower cost.

The ispClock devices' ability to store up to four timing and output configurations and easily switch between them further extends their utility by supporting easy clock margining (operating a circuit board at higher than typical frequency to evaluate design robustness) and power management (conserving dynamic power consumption by "downshifting" to a more efficient, lower frequency when performance is less critical). In-system programmability via the on-chip boundary scan port helps debug complex timing problems and tune individual network timing for best performance.

About Lattice Semiconductor
Lattice Semiconductor Corporation designs, develops and markets the broadest range of Field Programmable Gate Arrays (FPGA), Field Programmable System Chips (FPSC) and high-performance ISPTM Programmable Logic Devices (PLD), including Complex Programmable Logic Devices (CPLD), Programmable Analog Chips (PAC), and Programmable Digital Interconnect (GDX). Lattice also offers industry leading SERDES products. Lattice is "Bringing the Best Together" with comprehensive solutions for today's system designs, delivering innovative programmable silicon products that embody leading-edge system expertise.

Lattice products are sold worldwide through an extensive network of independent sales representatives and distributors, primarily to OEM customers in the fields of communications, computing, computer peripherals, instrumentation, industrial controls and military systems. Company headquarters are located at 5555 NE Moore Court, Hillsboro, Oregon 97124-6421, USA; telephone 503-268-8000, fax 503-268-8037. For more information about Lattice Semiconductor Corporation, visit

Lattice Semiconductor Corporation, Lattice (& design), L (& design), GDX, ISP, ispClock, PAC, PAC-Designer and specific product designations are either registered trademarks or trademarks of Lattice Semiconductor Corporation or its subsidiaries in the United States and/or other countries.

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