Cypress Semiconductor announced immediate availability of production volumes of the CY22xxx family of field-programmable clock generators. Operating at speeds up to 200 MHz, the timing devices provide highly stable, easily configurable clock outputs for use in a wide range of commercial and consumer applications, including switches, routers, computers, DVD players, and digital cameras.

"These devices allow designers to use a simple software utility to create a customized clock solution, similar to the way they customize logic solutions for a CPLD," said Ian Chen, director of marketing for Cypress's Timing Technology Division. "Instead of waiting months for a custom crystal or a custom PLL, designers can create a production-grade sample using an EPROM programmer in their labs in just thirty minutes or less. Furthermore, they can optimize a programmable clock for each application, guaranteeing peak performance. At any volume the programmable device is as cheap or cheaper than a custom ASIC."

As companies push to create a greater variety of communications and connectivity applications and bring them to market in the shortest possible time, component engineers who can no longer qualify a large number of custom solutions are pushing to standardize product development around programmable clocks. Manufacturers also benefit from easier inventory management. Since these devices can be programmed with different personalities, excess inventory can be re-targeted for different applications instead of being sold for pennies on the dollar.

Cypress Semiconductor's product portfolios include high-speed physical layer devices (PHYs), network search engines (NSEs), network coprocessors, datapath switching elements (DSEs), networking-optimized and micropower static RAMs; high-bandwidth multi-port and FIFO memories; high-density programmable logic devices; timing technology for PCs and other digital systems; and controllers for Universal Serial Bus.

Cypress Semiconductor, 3901 North First Street, San Jose, CA 95134. Tel: 408-943-2600; Fax: 408-943-6841 More information about Cypress is accessible at: http://www.cypress.com.

The revenue from general purpose oscillators has been flat to down over the last ten years, usurped by the custom clock chips that go into PC motherboards, notebooks, and printers. That shift also points to one of the reasons why there has been a healthy growth rate of custom clocks and programmable clocks over the last five years.

The Cypress CY223xx products are basically PLL-type devices that provide clocks. The CY223xx devices are the company's second generation of field programmable clocks.

The block diagram of the programmable clock shows a PLL. A PLL basically lines up two signals and makes them replicas of each other. But by manipulating the values that are put into the divide registers P, Q, and R, many frequencies based on the same input can be generated. In this family architecture they have 126 values of P, about 2,000 values of Q and 123 values of R, so if you mix all those together there are over 32 million settings. For every frequency there are 32 million combinations that generate 20 million unique frequencies. Additionally, there is a switch that allows any internal frequency source to be routed to any output pin. So the clock can be changed to match the component placement.

Cypress also allows the crystal load capacitance to change. Typically, when you use a crystal with a clock, each crystal manufacturer has slightly different requirements for what capacitance they want to see on the leads of the crystal. If you use a programmable crystal you can actually change the capacitive load setting to adjust the crystal's center frequency to an incoming reference. However, the curse of making a part programmable is that it can become very complicated to use unless there is a utility. So Cypress decided to provide software for all known Windows operating systems.

You may wonder how a programmable clock can perform better than a custom clock. If both the programmable and custom devices were made for one application then the performance of the programmable wouldn't be any better. But, if you are a manufacturer of a product such as a set top box you will need to have about 10 different versions of the set top box in production at the same time. The companies that make these set top boxes typically have someone that they call the clock guru. The clock guru copies down the clock requirements for each of the ten applications and writes a spec that creates a clock that is good for ten different uses. Then this expert goes to the custom clock vendors to have one built. Invariably, you over design and must accept a performance trade off. Cypress decided that instead of making one device that is trying to do ten things at the same time, they would use one device that can be customized ten different ways to do ten different things.

However, this also means that Cypress must already have thought of the way that you need to use a clock otherwise the clock can't be programmed for your application. Since this is a new way of designing a product, engineers must be aware of those differences. In other words some of the advantages of being able to tune a clock to a PCB with slightly different specs than what designer wanted are only advantages if the company is shrinking the design cycle. If designers are going to do the designing the old way - have a board ready, measure the impedance, and then the specify the clock - then the programmable clock is not being used to its potential.

This is a PC-based product and much of the capability of this product relies on software. But by late next year the company intends to enable it on the Web. When that happens a person could perform the programming on the web and determine the performance of their device right there.

The new programmable clock family from Cypress consists of the CY22392, CY22393, CY22394, CY22395 and CY22381. All members feature a serial interface, low voltage outputs (2.5V), a digital VCXO feature, speeds up to 200 MHz (400 MHz with LVPECL) and 30 percent lower period jitter/70 percent lower long-term jitter than previous generation parts.

These clock generators are available now, configured with three phase-locked loops (PLLs) and packaged in a 16-pin TSSOP. In volumes of 10,000, prices range from $1.90 for the CY22381 to $2.95 for the CY22395.