ICS291PGIT

Clock Generators, PLLs, Frequency Synthesizers Overview

The ICS291PGIT is a field-programmable spread spectrum clock synthesizer manufactured by Renesas Electronics Corporation. It generates up to six high-frequency CMOS clock outputs from a single low-frequency crystal or external clock input. The device utilizes three Phase-Locked Loops (PLLs) and contains One-Time Programmable (OTP) ROM for configuration storage. It supports output frequencies up to 200 MHz at 3.3 V, with configurable spread spectrum modulation to reduce electromagnetic interference. The unit operates on a 3.3 V supply voltage and features separate 1.8 V to 3.3 V output drive levels for two banks of three outputs each.

Clock Generators, PLLs, Frequency Synthesizers Feature Summary

• Triple PLL architecture generating up to six independent clock outputs
• Configurable spread spectrum modulation (center or down spread) for EMI reduction
• Field programmability via OTP ROM using IDT VersaClock software
• Separate VDDO power supplies (1.8 V to 3.3 V) for two output banks

Clock Generators, PLLs, Frequency Synthesizers Applications

• Replacing multiple crystals and oscillators in electronic systems
• Generating reference clocks for high-speed digital circuits
• Systems requiring controlled electromagnetic interference (EMI) through frequency modulation

Clock Generators, PLLs, Frequency Synthesizers Procurement Notes

Verify component authenticity as the ICS291PGIT is listed as obsolete. Confirm RoHS compliance status, noting that non-green parts reached end-of-life on May 13, 2010. Ensure the specific suffix matches the required temperature range and packaging format before procurement.

Clock Generators, PLLs, Frequency Synthesizers Selection Notes

Select the ICS291PGIT when a single device must replace multiple discrete oscillators to save board space. Use this part if the design requires field-programmable clock frequencies and spread spectrum capabilities. Verify that the target output frequencies fall within the 5–27 MHz input and up to 200 MHz output specifications.

Clock Generators, PLLs, Frequency Synthesizers Part Context

The ICS291 belongs to the VersaClock family of clock synthesizers originally developed by Integrated Device Technology (IDT), which was later acquired by Renesas Electronics. The 'PGIT' suffix indicates a Pb-free version packaged in a 20-pin TSSOP with industrial temperature rating (-40°C to +85°C).

Clock Generators, PLLs, Frequency Synthesizers Replacement Considerations

Factory programmed versions such as 291G-XX or 291GI-XX offer identical functionality but are pre-configured at the factory. These may serve as functional replacements if custom programming is not required.