M2021-11-622.0800T

Clock Generators, PLLs, Frequency Synthesizers Overview

The M2021-11-622.0800T is a VCSO-based clock jitter attenuator PLL manufactured by Integrated Circuit Systems, Inc., now part of Renesas Electronics. It integrates a proprietary SAW delay line to generate low phase noise clocks for optical network systems supporting 2.5–10 Gb/s data rates. The device operates on a single 3.3V supply and accepts differential LVDS/LVPECL or single-ended LVCMOS/LVTTL reference inputs. It provides two differential LVPECL outputs with selectable frequencies via pin-configurable dividers. Key features include narrow bandwidth control, loss-of-lock indication, and optional hitless switching compliance with SONET/SDH standards.

Clock Generators, PLLs, Frequency Synthesizers Feature Summary

• Integrated Voltage Controlled SAW Oscillator (VCSO) with < 0.5ps rms typical output jitter (12kHz to 20MHz offset range).
• Supports input reference frequencies from 10 MHz to 700 MHz and generates output frequencies from 15 MHz to 700 MHz.
• Features dual differential LVPECL outputs with post-PLL P-divider options (1, 4, 8, 32) and TriState capability.
• Includes Loss of Lock (LOL) indicator and Narrow Bandwidth (NBW) control pin for loop filter adjustment.

Clock Generators, PLLs, Frequency Synthesizers Applications

• Transmit reference clock generation for optical network systems (SONET/SDH).
• Jitter attenuation for stratum reference clocks in loop timing mode.
• Frequency translation for recovered clocks in telecommunications infrastructure.

Clock Generators, PLLs, Frequency Synthesizers Procurement Notes

Verify the specific suffix 'T' against the manufacturer's current ordering guide to confirm tape-and-reel packaging status. Confirm that the '11' designation aligns with the required industrial temperature grade (-40°C to +85°C) as specified in the datasheet. Ensure the fixed VCSO center frequency matches the system design requirements, as this parameter is defined at the time of order.

Clock Generators, PLLs, Frequency Synthesizers Selection Notes

Select the M2021 variant over M2020 if dual independent output channels are required, as M2021 supports two distinct LVPECL output pairs. Configure the MR_SEL and FIN_SEL pins to establish the appropriate M/R divider ratios for the target phase detector frequency. Ensure external loop filter components are selected based on the KVCO and desired loop bandwidth to maintain stability.

Clock Generators, PLLs, Frequency Synthesizers Part Context

This component belongs to the M2020/21 family of VCSO-based clock PLLs designed for high-performance networking applications. While originally produced by Integrated Circuit Systems (ICS), the product line is managed under Renesas Electronics following industry consolidation. The device is distinct from general-purpose oscillators due to its integrated SAW resonator and programmable PLL architecture.

Clock Generators, PLLs, Frequency Synthesizers Replacement Considerations

Direct replacements must support VCSO technology and similar jitter specifications (< 0.5ps rms). Verify compatibility with existing pin configurations and LVPECL output drivers. Alternative devices may require redesign of the external loop filter and power supply decoupling networks.